Document:

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                       CONFIDENTIAL TREATMENT REQUESTED

                                                                    Exhibit 10.8

                           NETWORK SERVICES AGREEMENT

                                 by and between

                              AMERICA ONLINE, INC.

                                       and

                                 BBN CORPORATION

                        Effective as of December 31, 1999
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                       CONFIDENTIAL TREATMENT REQUESTED

                                TABLE OF CONTENTS
                                -----------------

MASTER AGREEMENT

1.    BACKGROUND, OBJECTIVES AND WAIVER........................................1
   1.1.     Background and Objectives..........................................1
   1.2.     Termination of Original Agreement; Waiver..........................1

2.    TERM.....................................................................2

3.    PROVISION OF SERVICES....................................................2
   3.1.     General............................................................2
   3.2.     Resale of Dedicated Resources......................................3
   3.3.     Sale of Vendor Network.............................................3

4.    ORDERING.................................................................3
   4.1.     General............................................................3
   4.2.     Order Tracking.....................................................3

5.    ACCEPTANCE TESTING AND FINAL ACCEPTANCE..................................4

6.    PROPRIETARY RIGHTS.......................................................4
   6.1.     Ownership of Proprietary Information...............................4
   6.2.     Ownership of Vendor Network........................................4
   6.3.     Telephone Numbers..................................................4

7.    SERVICE LEVELS...........................................................4

8.    CHARGES AND TAXES........................................................5
   8.1.     General............................................................5
   8.2.     Taxes..............................................................5
   8.3.     Certain Obligations Corresponding to the Waiver....................6

9.    INVOICING AND PAYMENT....................................................6
   9.1.     Invoicing..........................................................6
   9.2.     Payment Due........................................................7
   9.3.     Accountability.....................................................7
   9.4.     Disputed Charges...................................................8

10.   AUDIT....................................................................8
   10.1.    Audit Rights.......................................................8
   10.2.    Records Retention..................................................8

11.   CONFIDENTIALITY..........................................................8
   11.1.    Confidential Information...........................................8
   11.2.    Obligations........................................................8
   11.3.    Exclusions.........................................................9
   11.4.    Residual Knowledge................................................10
   11.5.    Customer Data.....................................................10

12.   REPRESENTATIONS, WARRANTIES AND COVENANTS...............................10
   12.1.    Compliance with Specifications and Applicable Laws................10
   12.2.    Non-Infringement..................................................10
   12.3.    Technology........................................................10
   12.4.    Year 2000.........................................................11

13.   TERMINATION.............................................................12
   13.1.    Termination of Master Agreement for Cause.........................12

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   13.2.    No Implication Against Materiality................................13
   13.3.    Termination for Change of Control.................................13
   13.4.    Termination/Expiration Assistance; Transition Period..............14

14.   LIABILITY AND FORCE MAJEURE.............................................14
   14.1.    Liability Restrictions............................................14
   14.2.    Force Majeure.....................................................14

15.   INDEMNIFICATION.........................................................15

16.   GENERAL.................................................................15
   16.1.    Binding Nature and Assignment.....................................15
   16.2.    Continued Performance and Governing Law...........................16
   16.3.    Entire Agreement..................................................16
   16.4.    Notices...........................................................16
   16.5.    Counterparts......................................................17
   16.6.    Relationship of Parties...........................................17
   16.7.    Severability......................................................17
   16.8.    Waiver of Default.................................................18
   16.9.    Cumulative Remedies...............................................18
   16.10.   Survival..........................................................18
   16.11.   Publicity.........................................................18
   16.12.   Certain Regulatory Events.........................................18
   16.13.   Amendment.........................................................19
   16.14.   Incorporation by Reference........................................19
   16.15.   Construction......................................................20

SCHEDULE A  Definitions......................................................A-1

SCHEDULE B  Dial-Up Access Services, Service Levels, Pricing and
            Other Terms......................................................B-1

SCHEDULE C  Broadband Backhaul Services, Service Levels, Pricing
            and Other Terms..................................................C-1

SCHEDULE D  Other Services...................................................D-1

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                           NETWORK SERVICES AGREEMENT

This Network Services Agreement (together with the attached Schedules and
Exhibits, the "Agreement"), effective as of December 31, 1999 (the "Effective
Date"), is entered into by and between America Online, Inc., a Delaware
corporation with offices located at 22000 AOL Way, Dulles, VA 20166
("Customer"), and BBN Corporation, a Massachusetts corporation, with offices
located at 3 Van de Graaff Drive, Burlington, MA 01803 ("Vendor"). As used in
this Agreement, "Party" means either Customer or Vendor, as appropriate, and
"Parties" means Customer and Vendor. The Parties agree that the following terms
and conditions shall apply to the products and services to be provided by Vendor
under this Agreement in consideration of certain payments to be made by
Customer. Defined terms used but not defined in the body of this Master
Agreement or the Schedules (other than Schedule A) shall have the meanings given
such terms in Schedule A.

1.   BACKGROUND, OBJECTIVES AND WAIVER

     1.1. Background and Objectives.
          -------------------------

          This Agreement is being made and entered into with reference to the
          following:

          (a)  Customer is an interactive service provider that desires to
               purchase (i) fully managed, end-to-end dial-up access services,
               and (ii) certain broadband backhaul services.

          (b)  Customer and Vendor previously contracted for Vendor to provide
               certain dial-up access services in that certain BBN-AOL Dial-Up
               Network Services Agreement dated September 23, 1996, as amended
               by (i) that certain BBN-AOL Dial-Up Network Services Agreement
               Amendment 1, dated April 29, 1997, (ii) that certain BBN-AOL
               Dial-Up Network Services Agreement Amendment 2, dated September
               29, 1997, (iii) that certain BBN-AOL Dial-Up Network Services
               Agreement Amendment 3, dated January 29, 1998, (iv) that certain
               BBN-AOL Dial-Up Network Services Agreement Amendment 4, dated
               February 11, 1998, (v) that certain BBN-AOL Dial-Up Network
               Services Agreement Amendment 5, dated June 30, 1998 and (vi) that
               certain BBN-AOL Dial-Up Network Services Agreement Amendment 6,
               dated July 28, 1999 (such agreement as amended, the "Original
               Agreement").

     1.2. Termination of Original Agreement; Waiver.

          (a)  The Original Agreement is hereby terminated as of the Effective
               Date. Except to the extent otherwise provided in this Agreement,
               the obligations of the Parties arising under the Original
               Agreement before the Effective Date of this Agreement shall be
               governed by the Original Agreement. The obligations of the
               Parties arising after the Effective Date (including with respect
               to Vendor's provision of Services during the Term) shall be
               governed by this Agreement.

          (b)  As partial consideration for entering into this Agreement, for
               the respective waivers and releases set forth below (collectively
               the "Waiver"), and for Vendor's obligations set forth in Section
               8.3 of this Master Agreement, each

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               Party hereby irrevocably waives and releases all claims, torts,
               liabilities, debts, suits, demands, causes of action, actions and
               rights, whether known, unknown, contingent or fixed, against the
               other Party and its respective predecessors, current and former
               Affiliates, successors, assigns, attorneys, directors, officers,
               agents and employees arising from or pertaining to the Original
               Agreement; provided, however, that:

               (i)  nothing contained in the Waiver shall release the Parties
                    from their respective obligations under this Agreement
                    (including with respect to the installed Dedicated Dial-Up
                    Access Ports previously provided under the Original
                    Agreement that Vendor is obligated to continue to provide
                    pursuant to Schedule B of this Agreement); and

               (ii) nothing contained in the Waiver shall apply to disputes or
                    any other matters between the Parties under this Agreement,
                    or based upon or associated with the claims of unaffiliated
                    third parties arising under the Original Agreement or this
                    Agreement.

2.   TERM

     The term of the Master Agreement shall begin on the Effective Date and
     shall expire on December 31, 2006, unless terminated earlier in accordance
     with the Agreement or extended pursuant to the relevant section in the
     appropriate Schedule or otherwise by mutual written agreement (such period,
     as terminated earlier or so extended, the "Term"). Each Schedule to the
     Agreement shall be effective for the period of time during the Term set
     forth in such Schedule.

3.   PROVISION OF SERVICES

     3.1. General.
          -------

          (a)  This Agreement sets forth the terms and conditions under which
               Customer may purchase Services from Vendor. Customer may utilize
               the Services purchased hereunder for any lawful purpose including
               in connection with any service or product offering made available
               by Customer or its Special Affiliates during the Term, providing
               access to an AOL Information Service, providing the delivery of
               Internet access or providing other subscriber-related services to
               end-users. The Parties acknowledge that this Agreement does not:
               (a) grant to Vendor an exclusive privilege to sell or otherwise
               provide to Customer any products or services, or (b) except as
               otherwise provided by Section 3.2 of the Master Agreement, or as
               otherwise required by this Master Agreement or any of the
               Schedules, restrict Vendor from providing products or services to
               other customers of Vendor. Customer may contract with other
               suppliers for the procurement of any products or services.

          (b)  Customer shall (i) remain the single point-of-contact with Vendor
               with respect to those Services provided to Special Affiliates
               pursuant to this Agreement, including with respect to any claims,
               disputes or other actions that Special Affiliates desire to make
               against Vendor, (ii) remain obligated to perform its

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               payment obligations under the Agreement with respect to those
               Services provided by Vendor to Special Affiliates pursuant to
               this Agreement, and (iii) Customer agrees to indemnify and hold
               Vendor harmless for claims brought against Vendor by Special
               Affiliates associated with the Services provided by Vendor to
               Special Affiliates pursuant to this Agreement; provided, however,
               that nothing herein applies to claims brought directly by
               Customer for damages arising out of Services utilized by Special
               Affiliates. For purposes of the Agreement, Services provided to
               Special Affiliates pursuant to this Agreement shall be deemed to
               be Services provided to Customer.

     3.2. Resale of Dedicated Resources.
          -----------------------------

          Except as specifically set forth in Schedule B with respect to the
          Dedicated Dial-Up Services, Vendor shall not resell or offer to resell
          any dedicated Services ordered and accepted by Customer regardless of
          whether or not such Services are utilized by Customer.

     3.3. Sale of Vendor Network.
          ----------------------

     (a)  Notwithstanding anything to the contrary in this Agreement, Customer
          shall have the right of first refusal with respect to any sale or
          transfer other than to a Vendor Affiliate of any unit or division that
          has, as its primary business, the provision of Dedicated Dial-Up
          Access Services to Customer and has Dedicated Dial-Up Access Ports to
          Customer; provided, however, in no event shall Customer have such
          right of first refusal in connection with (i) the sale or transfer of
          a business unit that does not relate to the provision of Services to
          Customer or (ii) the sale or transfer of any Vendor assets to any
          entity created as a result of, or arising out of, the closing of the
          proposed merger of GTE Corporation and Bell Atlantic Corporation so
          long as the management of Vendor continues to have primary management
          responsibility of the new entity; provided further, however, that any
          transaction in which any assets of Vendor are transferred back to any
          Affiliate of the combined GTE/Bell Atlantic corporation shall not be
          covered by this Section.

4.   ORDERING

     4.1. General.
          -------

          The ordering of Services by Customer and the delivery of such Services
          by Vendor shall be governed by the terms and conditions set forth in
          the applicable Schedule of this Agreement corresponding to such
          Services.

     4.2. Order Tracking.
          --------------

          Vendor will provide Customer with weekly information on Orders as
          reasonably requested by Customer in a format consistent with that
          provided under the Original Agreement immediately prior to the
          Effective Date of this Agreement. Vendor will provide Customer with
          written reports relating to Orders as mutually agreed upon by the
          Parties.

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5.   ACCEPTANCE TESTING AND FINAL ACCEPTANCE

     Acceptance testing provisions associated with the Services are set forth in
     the applicable Schedule for such Services.

6.   PROPRIETARY RIGHTS

     6.1. Ownership of Proprietary Information.
          ------------------------------------

          (a)  All right, title and interest in Customer developed software and
               other Customer proprietary information (including any Customer
               software or Customer proprietary information which may be
               incorporated into written material or software delivered under
               this Agreement), including all intellectual property rights
               related thereto, will remain in Customer. Customer shall also
               have all ownership rights, including copyright, to all written
               reports prepared and delivered to Customer by Vendor under this
               Agreement.

          (b)  All right, title and interest in Vendor developed software and
               other Vendor proprietary information, including all intellectual
               property rights related thereto, will remain in Vendor; provided,
               however, any software developed by Vendor incidental to the
               performance of Services for Customer, the cost of which is
               separately charged to, and reimbursed by, Customer shall be
               jointly owned by Vendor and Customer, with no duty of accounting.

          (c)  All right, title and interest in software jointly developed by
               the Parties shall be jointly owned by Vendor and Customer, with
               no duty of accounting.

          (d)  With respect to Subsections (b) and (c) above, each Party hereby
               agrees to take all actions, and execute and deliver such
               documentation as is necessary to evidence the other Party's
               ownership interest in and to the developed Software.

          (e)  Each Party hereby grants to the other Party a limited license to
               utilize each other's software and other proprietary information
               in connection with Vendor's performance of, and Customer's
               receipt of, the Services.

     6.2. Ownership of Vendor Network.
          ---------------------------

          Except to the extent that Customer owns or has rights in certain
          equipment used to provide Dedicated Dial-Up Access Ports as of the
          Effective Date, or purchases Vendor Network assets pursuant to Section
          3.3 of the Master Agreement, Vendor retains title and ownership to the
          Vendor Network.

     6.3. Telephone Numbers.
          -----------------

          As between Vendor and Customer, Customer shall have title and
          ownership to all telephone numbers used to provide Dial-Up Access
          Services.

7.   SERVICE LEVELS

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     All Services provided by Vendor shall comply with the applicable Service
Levels.

8.   CHARGES AND TAXES

     8.1. General.
          -------

          Charges for a Service hereunder shall not begin to accrue until after
          Final Acceptance of the Service. Charges for any Service shall be as
          computed pursuant to the Schedule of this Agreement corresponding to
          such Service. All charges specified in the Schedules fully compensate
          Vendor for Services. Customer will not be liable to Vendor for any
          charges not expressly set forth in the Schedules or the Master
          Agreement unless such charges are mutually agreed upon by the Parties
          in writing. Customer shall only be obligated to pay for Services
          provided in accordance with the terms of this Agreement.

     8.2. Taxes.
          -----

          The Parties' respective responsibilities for taxes arising under or in
          connection with this Agreement shall be as follows:

          (a)  Vendor shall be responsible for any sales, use, excise,
               value-added, services, consumption, and other taxes and duties
               payable by Vendor on any goods or services that are used or
               consumed by Vendor in providing the Services where the tax is
               imposed on Vendor's acquisition or use of such goods or services
               and the amount of tax is measured by Vendor's costs in acquiring
               such goods or services.

          (b)  Customer shall be responsible for any sales, use, excise,
               value-added, services, consumption, or other tax that is assessed
               on any particular Service received by Customer from Vendor.
               Customer shall also be responsible for any sales, use, excise,
               value-added or consumption taxes imposed on goods purchased by
               Customer from Vendor under the Agreement. If and to the extent
               any tax described in this Subsection (b) is reduced or eliminated
               during the Term, Vendor shall reduce or eliminate any charges for
               such taxes, as appropriate. If and to the extent any tax
               described in this Subsection (b) is increased during the Term, or
               a new tax is imposed upon any particular Service received by
               Customer from Vendor, then Customer shall have full
               responsibility for such increase or tax.

          (c)  The Parties agree to cooperate with each other to enable each to
               more accurately determine its own tax liability. Neither Party
               will act unreasonably in assisting the other Party in minimizing,
               to the extent legally permissible, such other Party's tax
               liability to the extent legally permissible. Each Party shall
               provide and make available to the other any resale certificates,
               information regarding out-of-state or out-of-country sales or use
               of equipment, materials or services, and other exemption
               certificates or information reasonably requested by either Party.

          (d)  Each Party shall promptly notify the other Party of, and
               coordinate with the other Party the response to and settlement
               of, any claim for taxes asserted by

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               applicable taxing authorities for which a Party is responsible
               hereunder, it being understood that with respect to any claim
               arising out of a form or return signed by a Party to this
               Agreement, such Party shall have the right to elect to control
               the response to and settlement of the claim, but the other Party
               shall have all rights to participate in the responses and
               settlements that are appropriate to its potential
               responsibilities or liabilities. If Customer requests Vendor to
               challenge the imposition of any tax, Customer shall reimburse
               Vendor for the reasonable legal fees and expenses it incurs.
               Customer shall be entitled to any tax refunds or rebates granted
               to the extent such refunds or rebates are of taxes that were paid
               by Customer, including taxes charged to Customer as Out-of-Pocket
               Expenses. Customer shall be responsible for interest and
               penalties incurred to the extent such interest and penalties are
               related to taxes paid or payable by Customer.

8.3. Certain Obligations Corresponding to the Waiver.
     -----------------------------------------------

     Promptly after execution of this Agreement, Customer shall pay to Vendor
     [*Material Omitted and Separately Filed Under an Application for
     Confidential Treatment] dollars ($[*Material Omitted and Separately Filed
     Under an Application for Confidential Treatment]) which amount represents
     an off-set of (i) the [*Material Omitted and Separately Filed Under an
     Application for Confidential Treatment] dollars ($[*Material Omitted and
     Separately Filed Under an Application for Confidential Treatment]) withheld
     by Customer under the Original Agreement and (ii) the [*Material Omitted
     and Separately Filed Under an Application for Confidential Treatment]
     dollars ($[*Material Omitted and Separately Filed Under an Application for
     Confidential Treatment]) that Vendor has agreed to pass-through to Customer
     from [*Material Omitted and Separately Filed Under an Application for
     Confidential Treatment] or its Affiliates for [*Material Omitted and
     Separately Filed Under an Application for Confidential Treatment]
     specifically affecting the Customer network in [*Material Omitted and
     Separately Filed Under an Application for Confidential Treatment].

9.   INVOICING AND PAYMENT

     9.1. Invoicing.
          ---------

          (a)  Vendor will invoice Customer for amounts due under this Agreement
               (including with respect to provision of Services to Special
               Affiliates) on a monthly basis in arrears. Each invoice shall
               contain the same information as provided under the Original
               Agreement immediately prior to the Effective Date of this
               Agreement, additional, similar information with respect to the
               Broadband Backhaul Services and Other Services, and any
               additional information as the Parties may otherwise agree. Each
               invoice will separately state those charges for the Dial-Up
               Access Services that are attributable to the provision of
               backhaul functions. Out-of-Pocket Expenses, if any, and Monthly
               Pass-Through Expenses will be billed monthly based upon actual
               and accrued costs, and such expenses shall be trued up on a
               quarterly basis. Upon any request by Customer, Vendor will
               provide Customer with access to books and records (including
               bills and invoices) from third party providers for all
               Out-of-Pocket Expenses and Monthly Pass-Through

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               Expenses. Any refunds or credits arising from an Out-of-Pocket
               Expense reimbursed by Customer or a Monthly Pass-Through Expense
               shall be remitted to Customer, and Vendor shall report and
               transmit to Customer any misdirected refunds or credits.

          (b)  To the extent a credit may be due Customer pursuant to this
               Agreement, Vendor shall provide Customer with an appropriate
               credit against amounts then due and owing; if no further payments
               are due to Vendor, Vendor shall pay such amounts to Customer
               within thirty (30) calendar days. In the event such payment is
               not made to Customer when due, Vendor will pay a late fee equal
               to the lesser of (a) one (1) percent of the amount of such
               charges per month; or (b) the maximum amount permissible by law.

          (c)  The detailed accounting of actual and accrued costs described in
               Section 3.D of the Original Agreement will be limited to costs
               incurred in the first quarter of Customer's fiscal year 2000 and
               the final true-up with respect to accrued costs (as described in
               the Original Agreement) will be completed and provided to
               Customer by March 31, 2000; and with respect to actual costs,
               Vendor will use all commercially reasonable efforts to work with
               its providers to reconcile actual costs as soon as reasonably
               practicable. Subject to Section 8.3 of this Master Agreement and
               to the last sentence of Section 8.1(a)(i) of Schedule B, Vendor
               will invoice Customer for all amounts due under the Original
               Agreement as of the Effective Date, and Customer will pay to
               Vendor such amounts due, in accordance with Section 9.2 of this
               Master Agreement.

9.2. Payment Due.
     -----------

     Subject to the other provisions of this Article 9, all undisputed charges
     shall be due and payable by Customer within thirty (30) calendar days after
     receipt of a proper invoice for such amount. In the event that any such
     charges are not received by Vendor within five (5) business days after
     receipt by Customer of written notice from Vendor indicating that such
     charges have not been paid within such thirty-day period, then commencing
     as of the original due date, Customer will pay a late fee equal to the
     lesser of (a) one (1) percent of the amount of such charges per month; or
     (b) the maximum amount permissible by law. All undisputed amounts due and
     payable to Vendor under this Article 9 shall be paid, at Customer's option,
     either (i) by check payable to the order of Vendor or (ii) by electronic
     funds transfer to Vendor from account(s) designated by Customer.

9.3. Accountability.
     --------------

     Both Parties shall maintain complete and accurate records of and supporting
     documentation for the amounts billable or owed and credits applicable to
     either Party under the terms of this Agreement, in accordance with
     generally accepted accounting principles applied on a consistent basis.
     Both Parties agree to provide the other Party with documentation and other
     information with respect to any amount claimed or owed as may be reasonably
     requested by either Party to verify accuracy and compliance with the
     provisions of this Agreement.

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9.4. Disputed Charges.
     ----------------

     Customer shall pay undisputed charges when such payments are due under this
     Article 9. Customer may withhold payment of particular charges that
     Customer disputes in good faith. To the extent that Vendor is entitled to
     such payment withheld pursuant to resolution of the underlying dispute,
     Customer shall pay to Vendor such payments plus any interest accrued from
     the date such payments are withheld by Customer at a rate equal to one
     percent (1%) per month on the disputed amounts. Upon resolution of the
     dispute against Vendor, Vendor will pay Customer interest equal to one
     percent (1%) per month on the amounts overpaid or under-withheld by
     Customer.

10.  AUDIT

     10.1. Audit Rights.
           ------------

          Each Party, after reasonable notice, shall have the right to conduct
          reasonable audits of the other Party, through a third party
          independent auditor as selected by the Party conducting the audit or
          through any other mutually agreeable means, and subject to reasonable
          confidential requirements, to enforce a Party's rights and/or enforce
          the other Party's obligations under this Agreement.

     10.2. Records Retention.
           -----------------

          Until three (3) years after document creation, each Party will
          maintain, and provide to the other Party and its auditors access upon
          request to, records, documents and other information subject to audit
          under the Agreement.

11.  CONFIDENTIALITY

     11.1. Confidential Information.
           ------------------------

           Vendor and Customer each acknowledge that they may be furnished with,
           receive, or otherwise have access to Confidential Information (as
           defined below) of or concerning the other Party. As used in this
           Agreement and subject to Section 11.3 of the Master Agreement,
           "Confidential Information" means any information, in any form,
           furnished or made available directly or indirectly by one Party (the
           "Disclosing Party") to the other (the "Receiving Party") relating to
           or disclosed in the course of the negotiation or performance of this
           Agreement, that is, or should be reasonably understood to be,
           confidential or proprietary to the Disclosing Party, and shall
           include the material terms of this Agreement (including all
           information relating to prices and purchase commitments), invoices
           and any supporting information provided by Vendor or Customer with
           respect to such invoices, information audited pursuant to Article 10,
           all Customer Data, Customer's customer and member information,
           automatic number identification ("ANI") data and information, the
           relations of the Disclosing Party with its customers, employees and
           service providers, technical processes and formulas, source codes,
           product designs, sales, cost and other unpublished financial
           information, product and business plans, projections and marketing
           data.

     11.2. Obligations.
           -----------

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     (a)  Any proprietary rights in Confidential Information disclosed by a
          Party shall remain with such Party. Customer and Vendor shall only
          disclose Confidential Information of the other Party internally on a
          "need-to-know" basis. Customer and Vendor shall each use at least the
          same degree of care, but in any event no less than a reasonable degree
          of care, to prevent disclosing to third parties the Confidential
          Information of the other as it employs to avoid unauthorized
          disclosure, publication or dissemination of its own information of a
          similar nature; provided that a Party may disclose such information to
          an entity performing or receiving Services hereunder or to an
          independent third-party auditor on a "need-to-know" basis where (i)
          the provision or receipt of Services or audit by such entity is
          authorized under this Agreement, (ii) such disclosure is necessary or
          otherwise naturally occurs in that entity's scope of responsibility,
          and (iii) the entity agrees in writing to assume confidentiality
          restrictions no less stringent than those described in this Section
          11.2. Any disclosure to such entity shall be under the terms and
          conditions as provided herein.

     (b)  Each Party shall take reasonable steps to ensure that its employees,
          agents and to the extent applicable, third party auditors comply with
          this Article 11. In the event of any unauthorized disclosure or loss
          of, or inability to account for, any Confidential Information of the
          Disclosing Party, the Receiving Party shall promptly, at its own
          expense: (i) notify the Disclosing Party in writing; (ii) take such
          actions as may be necessary or reasonably requested by the Disclosing
          Party to minimize the violation; and (iii) cooperate in all reasonable
          respects with the Disclosing Party to minimize the violation and any
          damage resulting therefrom. With respect to any Confidential
          Information disclosed to the Receiving Party, the nondisclosure
          obligation shall last for five (5) years from the date of disclosure
          of such Confidential Information.

11.3. Exclusions.
      ----------

     (a)  "Confidential Information" shall exclude any particular information
          that (i) was, at the time of disclosure to it, lawfully in the public
          domain; (ii) after disclosure to it, is lawfully published or
          otherwise lawfully becomes part of the public domain through no fault
          of the Receiving Party; (iii) except for the material terms of the
          Agreement, was lawfully in the possession of the Receiving Party at
          the time of disclosure to it; (iv) was received after disclosure to it
          from a third party who had a lawful right to disclose such information
          to it without any obligation to restrict its further use or
          disclosure; and (v) was independently developed by the Receiving Party
          without reference to Confidential Information of the Disclosing Party.
          In addition, a Party shall not be considered to have breached its
          obligations by disclosing Confidential Information of the other Party
          to the minimum extent required to satisfy any legal requirement of a
          competent government body provided that, immediately upon receiving
          any such request and to the extent that it may legally do so, such
          Party advises the Disclosing Party promptly and prior to making such
          disclosure in order that the Disclosing Party may interpose an
          objection to such disclosure, take action to assure confidential
          handling of the Confidential Information, or take such other action as
          it deems appropriate to protect the Confidential Information.

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     (b)  Nothing in this Article 11 shall be construed or interpreted as a
          representation or agreement to restrict assignment or reassignment of
          a Party's employees. Subject to each Party's obligations under the
          Agreement, neither Party shall be precluded from participating in
          business activities that may be competitive with the other Party.

11.4. Residual Knowledge.
      ------------------

      Nothing contained in this Agreement shall restrict either Party from the
      use of any ideas, concepts, know-how, methodologies, processes,
      technologies, algorithms or techniques relating to the Services that
      either Party, individually or jointly, develops or discloses under this
      Agreement, provided that in doing so such Party does not breach its
      obligations under this Article or infringe the intellectual property
      rights of the other Party or third parties who have licensed or provided
      materials to such Party.

11.5. Customer Data.
      -------------

      (a)  Without limiting Vendor's obligations under Section 11.2 of the
           Master Agreement with respect to Customer Data, Vendor shall only use
           Customer Data to the extent necessary to fulfill its obligations
           under this Agreement.

      (b)  Vendor shall institute "standard industry practices" physical and
           logical security measures with respect to facilities and systems used
           to provide the Services, including with respect to any shared
           processing or network environments and with respect to the access and
           controls it affords to its employees, Affiliates and subcontractors
           (including the employees of each) to guard against, identify and
           promptly terminate the unauthorized access, alteration or destruction
           of Customer Data.

12.  REPRESENTATIONS, WARRANTIES AND COVENANTS

     12.1. Compliance with Specifications and Applicable Laws.
           --------------------------------------------------

           Vendor covenants that it shall perform the Services in accordance
           with the terms of this Agreement. Vendor represents that the Services
           offered to Customer are, and warrants that after the Effective Date
           Services purchased by Customer shall be, in conformance with
           applicable federal, state and local laws and regulations, including
           FCC requirements and specifications.

     12.2. Non-Infringement.
           ----------------

           Vendor warrants that the Services shall not knowingly infringe, and
           that Vendor shall perform its responsibilities under this Agreement
           in a manner that does not infringe, or constitute an infringement or
           misappropriation of, any patent, copyright, trademark, trade secret
           or other proprietary rights of Customer or any third party.

     12.3. Technology.
           ----------

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           Vendor covenants that in the event that Vendor provides any hardware
           and software upgrades as part of the Services, such upgrades shall be
           without additional charge to Customer. Vendor will implement software
           and hardware upgrades to the extent such upgrades are necessary to
           maintain the quality of Services as specified in this Agreement, stay
           consistent with industry standards and otherwise meet its obligation
           to provide Services hereunder.

     12.4. Year 2000.
           ---------

           Vendor represents that the Services offered to Customer are, and
           warrants that Services provided to Customer shall be, Year 2000
           Compliant. "Year 2000 Compliant" means that the Services satisfy the
           requirements set forth below:

           (a)  Limited Warranty. Vendor warrants that the Services will be Year
                ----------------
                2000 Compliant, pursuant to the terms of this Section 12.4
                (hereinafter referred to in this Section as the "Year 2000
                Compliance Limited Warranty"). Vendor warrants that in
                connection with Calendar-Related data and Calendar-Related
                processing of Date Data or of any System Date, the Services, as
                a whole or by its components, as to the Year 2000 will not
                malfunction, will not cease to function, will not generate
                incorrect data, will not produce incorrect results, and will
                represent dates without ambiguity when providing Calendar-
                Related data to and accepting Calendar-Related data from other
                automated, computerized, and/or software systems and users via
                use interfaces, electronic interfaces, and data storage.

                In the event of any Year 2000 Noncompliance with respect to the
                Services when and as specified herein, Vendor shall, as
                Customer's sole and exclusive remedy, repair or replace the
                affected Services within a reasonable period of time as
                determined by the severity of the failure and the level of
                effort necessary to correct such failure.

                Vendor shall meet the obligations set forth in this Year 2000
                Compliance Limited Warranty provided that all Customer or third
                party supplied computer software, computer firmware, and
                computer hardware that directly interface with the Services, co-
                exist with the Services, or directly influence the Services'
                operation, are also demonstrated to comply with this Year 2000
                Compliance Limited Warranty.

          (b)   Disclaimer. Except as provided by this Year 2000 Compliance
                ----------
                Limited Warranty, Vendor shall not be liable for any failure of
                the AOLnet to be Year 2000 Compliant.

          (c)   Definitions. For the purposes of this Year 2000 Compliance
                -----------
                Limited Warranty, the following defined terms shall have the
                following meanings:

                (i)   "AOLnet" means that portion of the Customer network in the
                      United States, which is managed by Vendor. "AOLnet" does
                      not include equipment, telephone circuits, networks,
                      network equipment, or telephone circuits not owned or
                      controlled by Vendor.

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<PAGE>

          (ii)  "Calendar-Related" refers to date values based on the Gregorian
                calendar, which includes Leap Years, and to all uses in any
                manner of those date values, including without limitation,
                manipulations calculations, conversions, comparisons, and
                presentation.

          (iii) "Date Data" means any Calendar-Related data the inclusive range
                January 1, 1900 through December 31, 2035, which the Services
                uses in any manner.

          (iv)  "System Date" means any Calendar-Related data value in the
                inclusive range January 1, 1985 through December 31, 2035
                (including the natural transition between such values), which
                the Services shall be able to use as its current date while
                operating.

          (v)   "Year 2000" Noncompliance" means any failure of the Services to
                be Year 2000 Compliant.

13.  TERMINATION

     13.1. Termination of Master Agreement for Cause.
           -----------------------------------------

           (a)  Customer's Right to Terminate. In addition to any other rights
                -----------------------------
                or remedies to which Customer may be entitled under this
                Agreement, in the event that:

                (i)   Vendor commits a material breach of this Agreement, which
                      breach is not cured within thirty (30) calendar days after
                      notice of breach from Customer to Vendor;

                (ii)  Vendor commits repeated material breaches of this
                      Agreement, even if cured;

                (iii) Vendor violates either Section 3.2 (Resale of Dedicated
                      Resources) or Vendor's core obligations with respect to
                      the most-favored customer provisions set forth in the
                      Schedules (e.g., Section 8.3(b) of Schedule B); or

                (iv)  there is a total or near-total outage of any of the
                      Services that, while it may last fewer than thirty (30)
                      calendar days, is widespread and prolonged enough to
                      justify a reasonable person, considering all relevant
                      industry standards, to terminate the Agreement,

                then Customer may, at its option and in its sole discretion,
                exercise the Agreement Termination Right for cause; provided,
                however, if Customer's termination for cause right is solely
                related to the Other Services, Customer may only exercise the
                Agreement Termination Right with respect to the Other Services.
                In the event of a termination of Customer's obligations with
                respect to the Purchase Commitments as a result of termination
                of the Agreement or any Schedule, Customer shall have no further
                liability to Vendor with respect to such

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                       CONFIDENTIAL TREATMENT REQUESTED

          Purchase Commitments. To the extent new services are added to this
          Agreement, defaults will be as specified therein.

     (b)  Vendor's Right to Terminate. In addition to any other rights or
          ---------------------------
          remedies to which Vendor may be entitled under this Agreement, in the
          event that

          (i)  Customer commits a material breach of this Agreement, including
               non-payment of undisputed amounts due and owing to Vendor in
               accordance with the terms of this Agreement, which breach is not
               cured within thirty (30) calendar days after notice of breach
               from Vendor to Customer; or

          (ii) Customer fails to meet its obligations with respect to the
               Purchase Commitments in accordance with and subject to the terms
               of this Agreement, which failure is not cured within thirty (30)
               calendar days after notice of failure from Vendor to Customer;
               provided, however, Customer shall be deemed not to have failed to
               meet its Purchase Commitments if it pays Vendor such amounts that
               Customer would have otherwise had to pay if Customer actually met
               such Purchase Commitments,

          then Vendor, at its option and in its sole discretion, may terminate
          this Agreement; provided, however, if Vendor's termination for cause
          right is solely related to the Other Services, Vendor may only
          exercise the Agreement Termination Right with respect to the Other
          Services. To the extent new services are added to this Agreement,
          defaults will be as specified therein.

13.2. No Implication Against Materiality.
      ----------------------------------

      The inclusion of any provision, obligation or duty in Section 13.1, or any
      statement in this Agreement, that a particular provision, obligation or
      duty is "material" shall not be construed to imply that any other
      provision, obligation or duty in this Agreement is not material.

13.3. Termination for Change of Control.
      ---------------------------------

      In the event of (a) a change in control of Vendor where such control is
      acquired, directly or indirectly, in a single transaction or series of
      related transactions, (b) all or substantially all of the assets of Vendor
      are acquired by or transferred to any entity, or (c) Vendor is merged with
      or into another entity to form a new entity, then at any time after any
      such event, Customer may, at its option and in its sole discretion,
      exercise the Agreement Termination Right; provided, however, nothing in
      this Section shall apply in a change in control resulting from or arising
      out of the closing of the proposed merger of GTE Corporation and Bell
      Atlantic Corporation (including any transaction in which any assets of
      Vendor are transferred back to any Affiliate of the combined GTE/Bell
      Atlantic corporation), unless the acquirer or merged entity is (i) a
      Significant Competitor of Customer (as such list of Significant
      Competitors may be modified from time-to-time by Customer on notice
      following August 31, 2000 to add additional significant competitors of
      Customer) or (ii) one of the following entities: MCI Worldcom, Sprint,
      Qwest or Level 3, or an Affiliate of such entities.

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     13.4. Termination/Expiration Assistance; Transition Period.
           ----------------------------------------------------

           Upon expiration of this Agreement or any Schedule, or upon any
           termination or cancellation of this Agreement or any Schedule by
           either Party (whether or not for cause), Customer may decommission
           all Services corresponding to the Agreement or any such Schedule, as
           applicable, and Vendor shall (i) provide Customer, or at Customer's
           request Customer's designee, reasonable assistance and consultation
           to enable Customer (or Customer's designee) to ensure a smooth and
           timely transition of network control and management to Customer (as
           applicable), and to transition Customer's purchase of services
           similar to the Services then expiring or being terminated to another
           vendor, and (ii) continue to provide the Services then expiring or
           being terminated to Customer (at prices then in effect as of the date
           of such expiration, termination or cancellation) and otherwise
           perform all of its obligations under this Agreement (such obligations
           described in this Section 13.4 collectively "Transition Assistance")
           for a period (the "Transition Period") to be determined by Customer
           in its sole and absolute discretion; provided, however, that unless
           otherwise specified in a Schedule to the Agreement, the Transition
           Period shall not be longer than twelve (12) months after the
           effective date of such expiration, termination or cancellation. If
           the provision of such Transition Assistance follows a notice of
           termination by Vendor pursuant to Section 13.1(b) of this Master
           Agreement as a result of Customer's non-payment of undisputed amounts
           owed to Vendor, then Customer shall pay Vendor monthly in advance
           plus an equitable portion of the unpaid charges giving rise to
           termination that compensates Vendor for the provision of such
           Transition Assistance. As part of its obligation to provide
           Transition Assistance, Vendor shall include transferring all rights
           to Customer at no additional charge, for Customer and its designees'
           exclusive use, any telephone numbers used in providing the Services
           so that Customer or its designee may utilize such numbers in
           providing services (subject to the provisions of Schedule B regarding
           Vendor's obligations to obtain such telephone numbers for Customer).

14.  LIABILITY AND FORCE MAJEURE

     14.1. Liability Restrictions.
           ----------------------

           The liability restrictions and limitation provisions for each Service
           provided hereunder are set forth in the associated Schedule for such
           Service.

     14.2. Force Majeure.
           -------------

           (a)  No Party shall be liable for any default or delay in the
                performance of its obligations under this Agreement if and to
                the extent such default or delay is caused, directly or
                indirectly, by fire, flood, lightning, earthquake, elements of
                nature or acts of God, strikes, lock-outs or other labor
                disturbance, riots, civil disorders, rebellions or revolutions
                in any country, or any other cause beyond the reasonable control
                of such Party; provided, however, that the non-performing Party
                is without fault in causing such default or delay, and such
                default or delay could not have been prevented by reasonable
                precautions and cannot reasonably be circumvented by the non-
                performing Party through the use of alternate sources,
                workaround plans or other means (each a "Force Majeure Event").

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                       CONFIDENTIAL TREATMENT REQUESTED

               The failure of a supplier or subcontractor of Vendor to perform
               under its agreement with Vendor shall not constitute a Force
               Majeure Event for Vendor except to the extent such supplier's or
               subcontractor's failure to perform is caused by a Force Majeure
               Event.

          (b)  In such event the non-performing Party shall be excused from
               further performance or observance of the obligation(s) so
               affected for as long as such circumstances prevail and such Party
               continues to use its commercially reasonable best efforts to
               recommence performance or observance whenever and to whatever
               extent possible without delay. In the event the Vendor is the
               non-performing Party, Customer shall be excused from paying for
               any Services affected by the Force Majeure Event. Any Party so
               delayed in its performance shall immediately notify the Party to
               whom performance is due by telephone (to be confirmed in writing
               within two (2) business days of the inception of such delay) and
               describe at a reasonable level of detail the circumstances
               causing such delay.

15.  INDEMNIFICATION

          Each Party agrees to indemnify, defend and hold harmless the other
          Party and its Affiliates and their respective officers, directors,
          employees, agents, successors, and assigns, from any and all losses,
          liabilities, damages and claims, and all related costs and expenses
          (including reasonable legal fees and disbursements and costs of
          investigation, litigation, settlement, judgment, interest and
          penalties) arising from, in connection with, or based on allegations
          of, any of the following:

          (a)  third party claims arising from the indemnifying Party's material
               breach of any obligation, representation or warranty under this
               Agreement;

          (b)  any claims of infringement of any patent, trademark, trade
               secret, copyright or other proprietary rights, alleged to have
               occurred based upon the provision by the indemnifying Party of
               materials, services or other resources to the indemnified Party;

          (c)  the death or bodily injury of any agent, employee, customer,
               business invitee, or business visitor of the indemnified Party or
               any other person caused by the tortious conduct of the
               indemnifying Party; or

          (d)  the damage, loss or destruction of any real or tangible personal
               property caused by the tortious conduct of the indemnifying
               Party.

16.  GENERAL

     16.1. Binding Nature and Assignment.
           -----------------------------

           This Agreement shall accrue to the benefit of and be binding upon the
           Parties hereto and any purchaser or any successor entity into which
           either Party has been merged or consolidated or to which either Party
           has sold or transferred all or substantially all of its assets.
           Neither Party may, or shall have the power to, assign this Agreement
           or delegate

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                        CONFIDENTIAL TREATMENT REQUIRED

          such Party's obligations hereunder without the prior written consent
          of the other, which consent shall not be unreasonably withheld or
          delayed, except that Customer may assign its rights and obligations
          under this Agreement without the approval of Vendor to an entity which
          acquires all or substantially all of the assets of Customer, to any
          Affiliate of Customer, or to a successor in a merger or acquisition of
          Customer. Notwithstanding anything to the contrary in this Section,
          but not affecting any of Customer's rights under Section 13.3,
          Customer hereby consents to the assignment of this Agreement to any
          entity created as a result of or arising out of the closing of the
          proposed merger of GTE Corporation and Bell Atlantic Corporation,
          including any transaction in which any assets of Vendor are
          transferred back to any Affiliate of the combined GTE/Bell Atlantic
          corporation.

    16.2. Continued Performance and Governing Law.

          (a)  Each Party agrees to continue performing its obligations under
               this Agreement while any dispute is being resolved except to the
               extent the issue in dispute precludes performance (dispute over
               payment shall not be deemed to preclude performance).

          (b)  This Agreement and performance under it shall be governed by and
               construed in accordance with the laws of the State of Delaware
               without regard to its choice of law principles.

    16.3. Entire Agreement.
          ----------------

          This Agreement, including any attached Schedules, sets forth the
          entire agreement of the Parties with respect to the transactions set
          forth herein.

    16.4. Notices.
          -------

          All notices, requests, demands, and determinations under this
          Agreement (other than routine operational communications or as
          otherwise specifically set forth herein (e.g., e-mail orders and
          Customer acceptance/rejection of Dedicated Dial-Up Access Ports or
          other Services)), shall be in writing and shall be deemed duly given
          (i) when delivered by hand, (ii) one (1) business day after being
          given to an express, overnight courier with a reliable system for
          tracking delivery, (iii) when sent by confirmed facsimile with a copy
          delivered by another means specified in this Section, or (iv) four (4)
          business days after the day of mailing, when mailed by United States
          mail, registered or certified mail, return receipt requested, postage
          prepaid, and addressed as follows:

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 -------------------------------------------------------------------------------
 To Customer:                                  To Vendor:
 -----------                                   ---------
 America Online, Inc.                          BBN Corporation
 12100 Sunrise Valley Drive                    9810 Patukent Woods Drive
 Reston, Virginia  20190                       Columbia, MD  21046
 Attn:  Geraldine MacDonald, Vice President    Attn:  Vice President and
        AOLnet Operations                             General Manager
 Fax:  (703) 265-5988                          Fax:  (410) 309-8315

 Copies to:                                    Copy to:
 ---------                                     -------
 America Online, Inc.                          GTE Internetworking
 22000 AOL Way                                 3 Van de Graaff Drive
 Dulles, Virginia  20166                       Burlington, MA 01803
 Attn: General Counsel                         Attn: General Counsel
 Fax:  (703) 265-1495                          Fax:  (781) 262-3408

 America Online, Inc.
 22000 AOL Way
 Dulles, Virginia  20166
 Attn:  President Of Business Affairs
 Fax:  (703) 265-1206
 -------------------------------------------------------------------------------

      A Party may from time to time change its address or designee for
      notification purposes by giving the other prior written notice of the new
      address or designee and the date upon which it will become effective.

16.5. Counterparts.
      ------------

      This Agreement may be executed in several counterparts, all of which taken
      together shall constitute one single agreement between the Parties hereto.

16.6. Relationship of Parties.
      -----------------------

      The Parties to this Agreement are independent contractors. Neither Party
      is an agent, representative, or partner of the other Party. Neither Party
      shall have any right, power or authority to enter into any agreement for
      or on behalf of, or incur any obligation or liability of, or to otherwise
      bind, the other Party. This Agreement shall not be interpreted or
      construed to create an association, agency, joint venture or partnership
      between the Parties or to impose any liability attributable to such a
      relationship upon either Party.

16.7. Severability.
      ------------

      In the event that any provision of this Agreement conflicts with the law
      under which this Agreement is to be construed or if any such provision is
      held invalid by a court with jurisdiction over the Parties, such provision
      shall be deemed to be restated to reflect as nearly as possible the
      original intentions of the Parties in accordance with applicable law. The
      remainder of this Agreement shall remain in full force and effect.

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     16.8.  Waiver of Default.
            -----------------

            No amendment, waiver or discharge hereof shall be valid unless in
            writing and signed by an authorized representative of the Party
            against which such amendment, waiver, or discharge is sought to be
            enforced. A delay or omission by either Party hereto to exercise any
            right or power under this Agreement shall not be construed to be a
            waiver thereof. A waiver by either of the Parties hereto of any of
            the covenants to be performed by the other or any breach thereof
            shall not be construed to be a waiver of any succeeding breach
            thereof or of any other covenant herein contained.

     16.9.  Cumulative Remedies.
            -------------------

            Except as otherwise expressly provided herein, all remedies provided
            for in this Agreement shall be cumulative and in addition to and not
            in lieu of any other remedies available to either Party at law, in
            equity or otherwise.

     16.10. Survival.
            --------

            Articles 10, 11, 14, 15, and 16 of this Master Agreement and,
            Section 1.2 of this Master Agreement, Schedule A, and Section 6.6 of
            Schedule B will survive the completion, expiration, termination or
            cancellation of the Agreement. In addition, any obligations which
            expressly or by their nature are to continue after termination,
            cancellation or expiration of the Agreement shall survive and remain
            in effect.

     16.11. Publicity.
            ---------

            (a)  Promotional Materials. Each Party shall submit to the other
                 ---------------------
                 Party, for its prior written approval, which will not be
                 unreasonably withheld or delayed, any marketing, advertising,
                 or other promotional materials to the extent such materials
                 reference the other Party or the other Party's trade names,
                 trademarks, and service marks (such materials the "Promotional
                 Materials").

            (b)  Press Releases. The Parties will prepare a mutually acceptable
                 --------------
                 joint press release for release following the Effective Date.
                 Each Party will submit to the other Party, for its prior
                 written approval, which will not be unreasonably withheld or
                 delayed, any press release or any other public statement (each,
                 a "Press Release") related to the transactions contemplated
                 hereunder. Without limiting the generality of the foregoing,
                 the inclusion in any such Press Release of any Confidential
                 Information or any information relating to prices or purchase
                 commitment terms of this Agreement shall be grounds for
                 withholding approval of such Press Release.

     16.12. Certain Regulatory Events.
            -------------------------

            In the event that Vendor is obligated under applicable law to
            provide any of the Services in accordance with tariffs filed with a
            governmental authority, then Vendor shall file the terms and
            conditions of this Agreement with such authority such that
            applicable law will require no change in the obligations of each
            Party under the Agreement. In the event that Vendor fails to file
            the terms and conditions of this Agreement in accordance with this
            Section, Customer may, at its option and in its sole discretion,
            exercise the

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            Agreement Termination Right for cause for those Schedules
            corresponding to the affected Services.

     16.13. Amendment.
            ---------

            This Agreement shall not be modified, amended or in any way altered
            except by an instrument in writing signed by both Parties.

     16.14. Incorporation by Reference.
            --------------------------

            Schedules A, B, C and D (including any Exhibits attached to such
            Schedules) are hereby incorporated by reference into this Master
            Agreement.

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     16.15. Construction.
            ------------

            The Parties agree that this Agreement was jointly drafted by the
            Parties and each Party further agrees that they shall not assert a
            claim that a particular provision should be construed against the
            other Party as the drafter of the provision. In addition, the
            headings and the table of contents in the Agreement are intended to
            be for reference purposes only and shall in no way be construed to
            modify or restrict, and shall not be considered in the construction
            or interpretation of, any of the terms or provisions of the
            Agreement.

IN WITNESS WHEREOF, Customer and Vendor have each caused this Agreement to be
signed and delivered by its duly authorized officer as of the Effective Date.

AMERICA ONLINE, INC.                   BBN CORPORATION

By: /s/ America Online, Inc.           By: /s/ Paul R. Gudonis
   --------------------------             -------------------------

Printed:                               Printed: Paul R. Gudonis
        ---------------------                  --------------------

Title:                                 Title: President
      ------------------------               ----------------------

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                                   SCHEDULE A

                                  Definitions

"Acceptance Criteria" means the criteria used to determine whether a Service is
ready for Final Acceptance. The Acceptance Criteria shall include the
requirements that the Service complies with all mutually agreed-upon testing
criteria as set forth in a Schedule to the Agreement and such other criteria as
may be developed and agreed upon by the Parties.

"Affiliate" of any entity means any other entity controlling, controlled by or
under common control with such entity.

"Agreement" has the meaning set forth in the preamble to the Master Agreement.

"Agreement Termination Right" means the right of a Party to terminate, without
cost or liability and as of the date specified in a written notice of
termination to Vendor, (a) the Schedule to which the breach giving rise to such
Agreement Termination Right relates, or (b) the entire Agreement. Any Schedule
not so terminated shall remain in full force and effect.

"Aggregate DSL Subscriber Lines" means the aggregate number of Subscriber Lines
providing xDSL broadband services that utilize the Broadband Backhaul Services
provided by Vendor or its Affiliates or the broadband backhaul services of any
other party. "Aggregate DSL Subscriber Lines" shall exclude Subscriber Lines of
any entity purchased, acquired, or merged with Customer or any Affiliate that,
as of the date of such purchase, acquisition or merger, are contractually
committed to another vendor of broadband backhaul services; provided that such
Subscriber Lines of such entity shall be excluded only for so long as the
duration (determined as of the date of such purchase, acquisition, or merger) of
such contractual commitment plus a mutually agreeable transition period.

"Aggregate Other Broadband Subscriber Lines" means the aggregate number of
Subscriber Lines providing broadband services that utilize the Broadband
Backhaul Services provided by Vendor or its Affiliates or the broadband backhaul
services of any other party. "Aggregate Other Broadband Subscriber Lines" shall
exclude (a) Subscriber Lines that transmit xDSL services, (b) Subscriber Lines
that utilize broadband services that are [*Material Omitted and Separately Filed
Under an Application for Confidential Treatment] service (i.e., a service where
the [*Material Omitted and Separately Filed Under an Application for
Confidential Treatment], and (c) Subscriber Lines of any entity purchased,
acquired, or merged with Customer or any Affiliate that, as of the date of such
purchase, acquisition or merger, are contractually committed to another vendor
of broadband backhaul services; provided that such Subscriber Lines of such
entity shall be excluded only for so long as the duration (determined as of the
date of such purchase, acquisition, or merger) of such contractual commitment
plus a mutually agreeable transition period.

"Aggregate Subscriber Lines" means the Aggregate DSL Subscriber Lines and
Aggregate Other Broadband Subscriber Lines, collectively.

"All New Ports MP Change Date" shall mean, for any New Dial-Up Market Price
Notice, the later of (a) the New Dial-Up Market Price Effective Date
corresponding to such New Dial-Up Market Price Notice, and (b) [*Material
Omitted and Separately Filed Under an Application for Confidential Treatment].

"ANI" has the meaning set forth in Section 11.1 of the Master Agreement.

"AOL Average" means, for a particular Service Level metric, the average
performance achieved with respect to such metric by other vendors of Customer
providing services similar to the Services corresponding to such Service Level
metric covering the same measurement period as the corresponding Service Level
measurement period.

"AOL Information Service" means a service (a) containing branding owned or
controlled by Customer or a Customer Affiliate, or using all or a portion of
Customer's or a Customer Affiliate's network or backend systems, or (b) in which
content, communications services and/or transactions are

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Network Services Agreement     America Online, Inc./BBN Corporation CONFIDENTIAL
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<PAGE>

provided to end-users through the use of any protocols, standards, platforms,
media or other methodology now or hereafter existing (including the Internet and
similar protocols, standards and platforms) from host server computers through
the use of client software resident on other computers or access devices.

"Applicable DUP Purchaser" has the meaning set forth in Section 8.3(b) of
Schedule B.

"Area Delivery Target" has the meaning set forth in Section 2.2(b) of Schedule
B.

"Base Port MP Change Date" shall mean, for any New Dial-Up Market Price Notice,
the later of (a) the New Dial-Up Market Price Effective Date corresponding to
such New Dial-Up Market Price Notice, and (b) [*Material Omitted and Separately
Filed Under an Application for Confidential Treatment].

"BPS", whether or not capitalized, shall mean bits per second.

"Broadband Backhaul" shall means the facility and associated managed services,
however provided in terms of technology, for receiving broadband traffic from
the public switched telephone network, a cable network, or a wireless network,
satellite network or other technologies, and delivering that traffic to a
Customer facility, where the end-user has initiated the connection. "Broadband
Backhaul" includes the provision of interconnection to an aggregation point and
the transport of bits from that aggregation point to a Customer facility.

"Broadband Backhaul Delivery Period" means, with respect to any New LATA, the
period commencing on the date Customer provides Vendor with the corresponding
New LATA Notice and ending on the later of (a) [*Material Omitted and Separately
Filed Under an Application for Confidential Treatment] days following such date,
and (b) if and only if Vendor has performed its obligations with respect to the
ATM intra-LATA interconnect (e.g., ordering of the circuit, management of the
associated third-party vendors), [*Material Omitted and Separately Filed Under
an Application for Confidential Treatment] days following the date on which the
local access provider is ready to activate the ATM intra-LATA interconnect in
such New LATA.

"Broadband Backhaul Market Vendor" has the meaning set forth in 7.2(a)(i)(2) of
Schedule C.

"Broadband Backhaul Purchase Commitments" means the DSL Purchase Commitment and
the Other Broadband Purchase Commitment, collectively.
"Broadband Backhaul Services" means (i) Broadband Backhaul ordered by Customer
pursuant to an Order to the extent accepted by Vendor pursuant to Schedule C and
managed network services associated therewith (including those services
described in Article 5 of Schedule C), and (ii) any other services described in
an Order to the extent accepted by Vendor pursuant to Schedule C, each of (i)
and (ii) as such services may change in accordance with the Agreement.

"Broadband Specifications" has the meaning set forth in Article 8 of Schedule C.

"Broadband Term" has the meaning set forth in Article 1 of Schedule C.

"Comparable Broadband Backhaul Services" means managed broadband backhaul
services that are comparable to Broadband Backhaul provided under Schedule C
(including comparable nationwide geographic distribution of Subscriber Lines
utilizing Broadband Backhaul and comparable terms and conditions).

"Comparable Dial-Up Services" means dedicated, managed dial-up access services
(not including usage-based dial-up access services) that are comparable to
Dial-Up Access provided under Schedule B (including comparable nationwide
geographic distribution of Dedicated Dial-Up Access Ports, and comparable terms
and conditions).

"Confidential Information" has the meaning set forth in Section 11.1 of the
Master Agreement.

"Covered Subscriber Line" has the meaning set forth in Section 9.1(b) of Exhibit
C-2 of Schedule C.

"Customer" has the meaning set forth in the preamble to the Master Agreement.

"Customer Data" means (i) all information or data provided to, or otherwise
learned or exposed to Vendor, Vendor's Affiliates or subcontractors by or on
behalf of Customer or end users of Customer's

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                       CONFIDENTIAL TREATMENT REQUESTED

services in conjunction with use of the Services (including such information
that is transmitted by or through the network(s) used to provide the Services),
and (ii) information derived from such information.

"Dedicated Dial-Up Access Port" is a Dial-Up Access Port that is (a) available
solely to the Customer and Special Affiliates, as applicable, and the end users
of Customer's and Special Affiliates' services, and (b) is not available to any
other party.

"Dial-Up Acceptance Test Period" has the meaning set forth in Section 2.7(a) of
Schedule B.

"Dial-Up Acceptance Testing" has the meaning set forth in Section 2.7(a) of
Schedule B.

"Dial-Up Access" is the facility and associated end-to-end, managed services,
however provided in terms of technology, for receiving analog or ISDN in-bound
calls from the public switched telephone network on demand and converting those
signals to digital form for transmission over digital networks, where the
end-user has initiated the call. "Dial-Up Access" includes the provision of
Dial-Up Access Ports.

"Dial-Up Access Port" is the capacity to offer Dial-Up Access to one (1)
incoming analog or ISDN in-bound call, plus signaling channels.

"Dial-Up Access Services" means (i) the "modems," managed, end-to-end network
services associated therewith, provided by Vendor to Customer under the Original
Agreement, (ii) Dial-Up Access ordered by Customer pursuant to an Order to the
extent accepted by Vendor pursuant to Schedule B and fully managed, end-to-end
network services associated therewith (including those services described in
Article 6 of Schedule B, and (iii) any other services described in an Order to
the extent accepted by Vendor pursuant to Schedule B, each of (i), (ii) and
(iii) as such services may change in accordance with the Agreement.

"Dial-Up Access Specifications" mean those Specifications described in Section
9.1 of Schedule B.

"Dial-Up Access Term" shall have the meaning set forth in Article 1 of Schedule
B.

"Dial-Up Market Vendor" has the meaning set forth in Section 8.3(a)(i)(2) of
Schedule B.

"Dial-Up Market Vendor Trigger" has the meaning set forth in Section 8.3(a)(i)
of Schedule B.

"Dial-Up Nonconformity" has the meaning set forth in Section 2.7(b)(i) of
Schedule B.

"Dial-Up Purchase Commitment" has the meaning set forth in Section 2.8(a) of
Schedule B.

"Disclosing Party" has the meaning set forth in Section 11.1 of the Master
Agreement.

"DSL Purchase Commitment" has the meaning set forth in Section 2.1 of Exhibit
C-1 of Schedule C.

"Effective Date" has the meaning set forth in the preamble to the Master
Agreement.

"Existing Calling Areas" means any rate center or calling area in which Vendor
(a) before the Effective Date provided, or agreed to provide, Dial-Up Access
Services to Customer (e.g., pursuant to the Original Agreement), or (b) during
the Term provides, or agrees to provide (e.g., pursuant to an Order), Dial-Up
Access Services to Customer.

"Existing Dedicated Dial-Up Access Port" has the meaning set forth in Section
8.1(b) of Schedule B.

"Existing LATA" means, at any given point in time, any LATA in which Vendor has
already provisioned Broadband Backhaul for xDSL for any customer.

"Final Acceptance" has the meaning set forth in Section 2.7(c) of Schedule B.

"Force Majeure Event" has the meaning set forth in Section 14.2 of the Master
Agreement.

"Include," "includes", and "including", whether or not capitalized, shall mean
"include but are not limited to", "includes but is not limited to", and
"including but not limited to", respectively.

"Incremental New Ports MP Change Date" shall mean, for any New Dial-Up Market
Price Notice, the later of (a) the New Dial-Up Market Price Effective Date
corresponding to such New Dial-Up Market Price Notice, and (b) [*Material
Omitted and Separately Filed Under an Application for Confidential Treatment]..

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                       CONFIDENTIAL TREATMENT REQUESTED

"L2TP" means Layer Two Tunneling Protocol.

"Leased Items" has the meaning set forth in Section 8.1(a)(ii) of Schedule B.

"Master Agreement" shall mean the Agreement excluding the Schedules to the
Agreement.

"Measurement Date" has the meaning set forth in Section 3.1 of Exhibit C-1 of
Schedule C.

"Monthly Aggregate Subscriber Line Charge" has the meaning set forth in Section
2.3(a) of Exhibit C-2 of Schedule C.

"Monthly DAP Charge" has the meaning set forth in Section 8.1(b) of Schedule B.

"Monthly EDAP Charge" has the meaning set forth in Section 8.1(a) of Schedule B.

"Monthly Pass-Through Expenses" has the meaning set forth in Section 7.1(b) of
Schedule C.

"Monthly Per Subscriber Line Charge" has the meaning set forth in Section 2.1 of
Exhibit C-2 of Schedule C.

"Monthly Subscriber Line Aggregate" has the meaning set forth in Section 2.3(a)
of Exhibit C-2 of Schedule C.

"Monthly Target" has the meaning set forth in Section 2.2 of Schedule B.

"New Broadband Backhaul Market Price" has the meaning set forth in Section
7.2(a)(i)(1) of Schedule C.

"New Broadband Backhaul Market Price Effective Date" means the date that is
ninety (90) calendar days after the New Broadband Backhaul Market Price Notice
Date corresponding to a New Broadband Backhaul Market Price Notice provided by
Customer.

"New Broadband Backhaul Market Price Notice" has the meaning set forth in
Section 7.2(a)(ii) of Schedule C.

"New Broadband Backhaul Market Price Notice Date" has the meaning set forth in
Section 7.2(a)(ii) of Schedule C.

"New Broadband Backhaul Market Price Response" has the meaning set forth in
7.2(a)(ii) of Schedule C.

"New Calling Area" means any rate center or calling area which is not an
Existing Calling Area.

"New Dial-Up Market Price" has the meaning set forth in Section 8.3(a) of
Schedule B.

"New Dial-Up Market Price Effective Date" means the date that is ninety (90)
calendar days after the New Dial-Up Market Price Notice Date corresponding to a
New Dial-Up Market Price Notice provided by Customer.

"New Dial-Up Market Price Notice" has the meaning set forth in Section
8.3(a)(ii) of Schedule B.

"New Dial-Up Market Price Notice Date" has the meaning set forth in Section
8.3(a)(ii) of Schedule B.

"New Dial-Up Market Price Response" has the meaning set forth in Section
8.3(a)(ii) of Schedule B.

"New LATA" means, at a given point in time, any LATA in which Vendor has not
already provisioned Broadband Backhaul for xDSL for any customer.

"New LATA Notice" has the meaning set forth in Section 1(c) of Schedule C.

"New Port" means any Dedicated Dial-Up Access Port that is not a Existing
Dial-Up Access Port.

"NOC" means a network operations center.

"Non-Terminable Breach" means a breach that does not, in and of itself, give
rise to Customer's right to exercise the Agreement Termination Right.

"Normalization Methodology" has the meaning set forth in Section 8.4(a) of
Schedule B.

"Order" means any valid order submitted by Customer pursuant to a Schedule to
this Agreement to the extent accepted or deemed accepted by Vendor pursuant to
such Schedule.

"Order Fulfillment Period" has the meaning set forth in Section 2.2 of Schedule
B.

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                       CONFIDENTIAL TREATMENT REQUESTED

"Original Agreement" has the meaning given in Section 1.1(b) of the Master
Agreement.

"Other Broadband Purchase Commitment" has the meaning set forth in Section 2.2
of Exhibit C-1 to Schedule C.

"Other Services Purchase Commitment" has the meaning set forth in Schedule D.

"Other Vendors' Decom Share" means for any calendar quarter, the amount
calculated as (a) the total number of Dedicated Dial-Up Access Ports (including
usage-based Dial-Up Access Services adjusted using the Normalization
Methodology) provided to Customer other than by Vendor that are decommissioned
by Customer in such quarter, divided by (b) the total number of Dedicated
Dial-Up Access Ports (including usage-based Dial-Up Access Services adjusted
using the Normalization Methodology) provided to Customer other than by Vendor
that are installed and accepted at the beginning of such quarter.

"Out-of-Pocket Expenses" shall mean reasonable, verifiable and actual
out-of-pocket expenses and associated taxes, if any, incurred by a Party, but
excluding that Party's overhead costs (or allocations thereof), administrative
expenses or other mark-ups.

"Owned Items" has the meaning set forth in Section 8.1(a)(ii) of Schedule B.

"Party" and "Parties" has the meaning set forth in the preamble to the Master
Agreement.

"Peak Resale Window" has the meaning set forth in Section 4(b) of Schedule B.

"POP" means point of presence.

"Pre-Term Private Line Agreements" has the meaning set forth in Schedule D.

"Press Release" has the meaning set forth in Section 16.11(b) of the Master
Agreement.

"Private Line Services" has the meaning set forth in Schedule D.

"Promotional Materials" has the meaning set forth in Section 16.11(a) of the
Master Agreement.

"Purchase Commitments" means (i) the Dial-Up Purchase Commitment, (ii) the
Broadband Backhaul Purchase Commitments, and (iii) the Other Services Purchase
Commitment, collectively.

"Receiving Party" has the meaning set forth in Section 11.1 of the Master
Agreement.

[*Material Omitted and Separately Filed Under an Application for Confidential
Treatment] has the meaning set forth in Section 8(e) of Schedule C.

"Reportless Ports" has the meaning set forth in Section 8.5(a) of Schedule B.

"Resold Dial-Up Access" has the meaning set forth in Section 4(a) of Schedule B.

"Service Levels" means the quantitative and qualitative service levels
identified as such the Schedules to this Agreement.

"Services" means, collectively (i) Dial-Up Access Services, (ii) Broadband
Backhaul Services, (iii) Other Services, and (iv) any other services that the
Parties mutually agree in writing that are governed by the terms of this
Agreement.

"Significant Competitor" means, solely with respect to Section 13.3 of the
Master Agreement, any of the following entities or their Affiliates (which
entities may be modified from time-to-time by Customer on notice following
August 31, 2000): [*Material Omitted and Separately Filed Under an Application
for Confidential Treatment].

"Special Affiliate" means, with respect to Customer, (i) Customer's Affiliates,
(ii) any other entity in which Customer holds, either directly or indirectly, at
least an [*Material Omitted and Separately Filed Under an Application for
Confidential Treatment] equity interest, or (iii) any entity which operates or
distributes, or is authorized to operate or distribute, an AOL Information
Service.

"Specifications" means the specifications and other requirements for the
Services identified as such in a Schedule to the Agreement.

"Subscriber Line" means a dedicated connection, between an end user of services
of Customer or one of its Affiliates and an aggregation point, that is

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<PAGE>

                       CONFIDENTIAL TREATMENT REQUESTED

activated and purchased by Customer or one or its Affiliates to provide services
to such end user.

"Term" has the meaning set forth in Article 2 of the Master Agreement.

"Transition Assistance" has the meaning set forth in Section 13.4 of the Master
Agreement.

"Transition Period" has the meaning set forth in Section 13.4 of the Master
Agreement.

"Valid Order Rejection Reason" has the meaning set forth in Section 2.3(a) of
Schedule B.

"Vendor" has the meaning set forth in the preamble to the Master Agreement.

"Vendor Broadband Subscriber Line" means a Subscriber Line used to transmit
broadband services that utilize the Broadband Backhaul Services provided by
Vendor or its Affiliates.

"Vendor Decom Share" means for any calendar quarter, the amount calculated as
(a) the total number of Dedicated Dial-Up Access Ports (including usage-based
Dial-Up Access Services adjusted using the Normalization Methodology) provided
by Vendor that are decommissioned by Customer in such quarter, divided by (b)
the total number of Dedicated Dial-Up Access Ports (including usage-based
Dial-Up Access Services adjusted using the Normalization Methodology) provided
by Vendor that are installed and accepted at the beginning of such quarter.

"Vendor ISP Affiliate" means any Affiliate of Vendor that offers online or
Internet connectivity services (e.g., an Internet service provider) to
consumers.

"Vendor Network" means any and all of the network or networks that support
Services ordered and accepted by Customer hereunder.

"Waiver" has the meaning set forth in Section 1.2(b) of the Master Agreement.

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Network Services Agreement     America Online, Inc./BBN Corporation CONFIDENTIAL
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                       CONFIDENTIAL TREATMENT REQUESTED

                                   SCHEDULE B

        Dial-Up Access Services, Service Levels, Pricing and Other Terms

1.   TERM

     The term of this Schedule B shall begin on the Effective Date and shall
     expire on December 31, 2006, unless terminated earlier in accordance with
     the Agreement, or extended by mutual written agreement (such period, as
     terminated earlier or so extended, the "Dial-Up Access Term").

2.   ORDERING

     2.1. New Markets.

          Vendor from time to time shall deliver to Customer a listing of any
          new rate centers or calling areas that are in addition to the Existing
          Calling Areas within which Vendor is willing to provide Dial-Up Access
          Services.

     2.2. Customer Submission of Orders.
          -----------------------------

          To order any Dial-Up Access Services, Customer shall submit to Vendor
          an order for such services covering the three-calendar month period
          beginning at least ninety (90) days following submission of the order
          (such three-month period the "Order Fulfillment Period"). Each order
          will set forth the following:

          (a)  the cumulative number of Dedicated Dial-Up Access Ports that
               Vendor must have installed and activated as of the end of each
               calendar month of an Order Fulfillment Period (for each calendar
               month, such number the "Monthly Target"), and

          (b)  the number of incremental Dedicated Dial-Up Access Ports for each
               calling area ordered by Customer during an Order Fulfillment
               Period (for each calling area, the "Area Delivery Target").

          Each order will be clearly marked as such, and will be delivered by
          Customer via electronic mail to such individuals designated in writing
          from time to time by Vendor. An e-mailed order will be valid only if
          it is submitted by the Vice President of AOLnet Operations, the
          Director for AOLnet Capacity Planning, or a designee of either.

     2.3. Vendor Acceptance or Rejection of Orders.
          ----------------------------------------

          (a)  Acceptance and Rejection Process.
               --------------------------------

               Vendor shall, within ten (10) business days after receipt of a
               valid order pursuant to Section 2.2 of this Schedule B, notify
               Customer of one of the following:

               (i)  its acceptance of such order; or

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<PAGE>

                       CONFIDENTIAL TREATMENT REQUESTED

               (ii) its rejection of such order in whole or in part; provided
                    that Vendor may reject an order if and only to the extent
                    (1) the Monthly Target for a calendar month exceeds the
                    prior month's Monthly Target by more than [*Material Omitted
                    and Separately Filed Under an Application for Confidential
                    Treatment] Dedicated Dial-Up Access Ports, (2) such order
                    requests Dial-Up Access Services to be delivered in a New
                    Calling Area, (3) such order does not reflect the same
                    approximate weighted distribution of Dedicated Dial-Up
                    Access Ports across Existing Calling Areas, or (4) such
                    order requests the provision of Dedicated Dial-Up Access
                    Ports in excess of the Dial-Up Purchase Commitment (each of
                    (1), (2), (3) and (4) a "Valid Order Rejection Reason").

               If Vendor fails to provide Customer with such notice within such
               ten-day period, then such order shall be deemed accepted by
               Vendor. Vendor shall be obligated to deliver, in accordance with
               this Schedule B, the Dial-Up Access Services requested by
               Customer in an order to the extent such order is accepted or
               deemed accepted by Vendor. If Vendor rejects an order (or a
               portion thereof) for the reason described in Subsection (ii)(3)
               above, following notice of such objection by Vendor, the Parties
               will mutually agree on an equitable resolution consistent with
               the intent of this Section.

          (b)  Rejections by Vendor.
               --------------------

               To the extent that Vendor rejects an order (or portion thereof)
               for any reason other than a Valid Order Rejection Reason, the
               Dial-Up Purchase Commitment shall be reduced by the number of
               Dedicated Dial-Up Access Ports wrongfully rejected by Vendor.

          (c)  Additional Tasking.
               ------------------

               For any Order Fulfillment Period, in the event Vendor requests,
               Customer will provide Vendor with additional tasking of Dedicated
               Dial-Up Access Ports for Existing Calling Areas; provided,
               however, that such additional tasking shall not result in total
               tasking in excess of [*Material Omitted and Separately Filed
               Under an Application for Confidential Treatment] Dedicated
               Dial-Up Access Ports above the Monthly Target for the third month
               of the such Order Fulfillment Period. Customer will designate the
               Existing Calling Areas in which any of the Dedicated Dial-Up
               Access Ports corresponding to such additional tasking will be
               provided by Vendor. Any additional tasking shall not affect the
               Monthly Targets.

     2.4. Cancellation Without Cause and Rescheduling of Orders.
          -----------------------------------------------------

          (a)  Pre-Acceptance or Pre-Rejection Cancellation or Modification by
               ---------------------------------------------------------------
               Customer.
               --------

               Prior to acceptance or rejection of an order by Vendor, Customer
               may rescind or modify, in whole or in part in its sole
               discretion, such order.

          (b)  Post-Acceptance Cancellation or Modification by Customer.
               --------------------------------------------------------

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                       CONFIDENTIAL TREATMENT REQUESTED

               (i)  Customer may cancel or modify an Order in whole or in part
                    at any time in its discretion prior to the delivery of the
                    corresponding Dedicated Dial-Up Access Ports set forth in
                    such Order; provided, however, that except to the extent
                    otherwise agreed by Vendor, such cancellation or
                    modification shall not result in circumstances that would
                    constitute a Valid Order Rejection Reason. For any such
                    cancellation or modification, Customer will pay to Vendor
                    any incremental Out-of-Pocket Expenses actually incurred as
                    a result of such cancellation or modification and that could
                    not reasonably have been avoided by Vendor. Customer shall
                    have no liability to Vendor for an Order cancelled pursuant
                    to this Subsection (i) other than payment to Vendor of such
                    Out-of-Pocket Expenses.

               (ii) Customer's cancellation or modification of an Order pursuant
                    to this Subsection (b) shall not relieve Customer of its
                    obligations with respect to the Dial-Up Purchase Commitment.
                    In the event of significant changes to an Order by Customer,
                    Vendor may provide Customer with notice of impaired ability
                    to deliver, and the Parties shall mutually agree upon
                    appropriate changes to the Monthly Targets.

     2.5. Delivery.
          --------

          (a)  Notification of Delivery by Vendor.
               ----------------------------------

               Vendor shall only deliver Dedicated Dial-Up Access Ports that
               Vendor reasonably and in good faith believes will satisfy the
               applicable Acceptance Criteria. Upon delivery of any Dedicated
               Dial-Up Access Port (but no sooner than such delivery), Vendor
               shall provide to Customer notification of such delivery by e-mail
               to the Vice President of AOLnet Operations, the Director for
               AOLnet Capacity Planning, or a designee of either. For purposes
               of Subsection (e) of Section 2.5, delivery of any Dedicated
               Dial-Up Access Port shall be deemed made upon Customer's receipt
               of such e-mail from Vendor.

          (b)  Early Delivery By Vendor.
               ------------------------

               Vendor may deliver Dedicated Dial-Up Access Ports ordered by
               Customer before the commencement of the corresponding Order
               Fulfillment Period.

          (c)  Initial Testing Failure of Dedicated Dial-Up Access Ports.
               ---------------------------------------------------------

               Notwithstanding the deemed delivery date described in the last
               sentence of Subsection (a) of this Section, if any Dedicated
               Dial-Up Access Port provided in a month is not accepted by
               Customer prior to the 15th day of the next month, then such
               Dedicated Dial-Up Access Port will be deemed not to have been
               delivered during the first month.

          (d)  Delivery of Additional Tasking.
               ------------------------------

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                       CONFIDENTIAL TREATMENT REQUESTED

               In any month, Customer shall not be required to accept any
               Dedicated Dial-Up Access Ports in excess of [*Material Omitted
               and Separately Filed Under an Application for Confidential
               Treatment] Dedicated Dial-Up Access Ports above the Monthly
               Target for such month. With respect to any calling area, Customer
               shall not be required to accept any more Dedicated Dial-Up Access
               Ports in excess of the then-current Area Delivery Target for such
               calling area.

          (e)  Vendor Failures to Deliver.
               --------------------------

               (i)  Failure to Meet Monthly Target. If Vendor fails to deliver
                    ------------------------------
                    the Monthly Target in any month by more than [*Material
                    Omitted and Separately Filed Under an Application for
                    Confidential Treatment] Dedicated Dial-Up Access Ports, then
                    Customer may reduce the Dial-Up Purchase Commitment by the
                    number of Dedicated Dial-Up Access Ports over [*Material
                    Omitted and Separately Filed Under an Application for
                    Confidential Treatment] that Vendor fails to so deliver.

               (ii) Late Delivery.
                    -------------

                    Vendor shall use demonstrable good faith diligent efforts to
                    deliver Dedicated Dial-Up Access Ports in accordance with an
                    Order prior to the end of the corresponding Order
                    Fulfillment Period. Customer may reduce the Dial-Up Purchase
                    Commitment by the number of Dedicated Dial-Up Access Ports
                    included in an Order (A) for which Vendor has not delivered
                    a substantial portion of a Area Delivery Target by the end
                    of the corresponding Order Fulfillment Period and (B) with
                    respect to which Vendor has not used such efforts. In
                    addition, Customer may cancel, at no cost or liability to
                    Customer, the unfilled portion of the Order pertaining to
                    such Dedicated Dial-Up Access Ports. In the event of such
                    cancellation, Customer shall have no payment obligations to
                    Vendor with respect to the Dedicated Dial-Up Access Ports
                    corresponding to the cancelled portion or portions of the
                    Order. Upon Customer's request, Vendor shall provide
                    Customer with information and supporting documentation which
                    demonstrates Vendor's good faith diligent efforts to deliver
                    all Dedicated Dial-Up Access Ports set forth in an Order
                    prior to the end of the corresponding Order Fulfillment
                    Period (e.g., documents showing Vendor's ordering of
                    circuits from an access provider necessary to provision such
                    ordered Dedicated Dial-Up Access Ports as well as the
                    corresponding response from such access providers (e.g.,
                    firm order commitment)).

     2.6. Ordering Process Review.
          -----------------------

          The Parties acknowledge that the ordering process set forth in this
          Article 2 may require modification during the Dial-Up Access Term, and
          that in such event the Parties shall meet to discuss amending this
          Schedule to reflect any mutually agreed-upon modifications.

     2.7. Acceptance Testing and Final Acceptance.
          ---------------------------------------

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                       CONFIDENTIAL TREATMENT REQUESTED

          (a)  Acceptance Testing. Dedicated Dial-Up Access Ports ordered
               ------------------
               hereunder will require acceptance testing by Customer as
               described in this Section. Customer will have up to a [*Material
               Omitted and Separately Filed Under an Application for
               Confidential Treatment] business day period from the date such
               Dedicated Dial-Up Access Ports are delivered to Customer (the
               "Dial-Up Acceptance Test Period") in which to perform any
               reasonable testing as Customer in its sole discretion deems
               appropriate to determine whether such Dedicated Dial-Up Access
               Ports conform to their applicable Acceptance Criteria (the
               "Dial-Up Acceptance Testing"). If such Dedicated Dial-Up Access
               Ports meet their applicable Acceptance Criteria, Customer will
               notify Vendor (by electronic mail) that such Dedicated Dial-Up
               Access Ports have received Final Acceptance pursuant to
               Subsection (c) of this Section. Dedicated Dial-Up Access Ports
               activated and accepted by Customer prior to the Effective Date in
               accordance with the Original Agreement will be deemed accepted
               for purposes of this Agreement.

          (b)  Failure to Satisfy Acceptance Criteria.
               --------------------------------------

               (i)   If Dedicated Dial-Up Access Ports fail to conform to their
                     Acceptance Criteria (each such failure a "Dial-Up
                     Nonconformity"), Customer will notify Vendor within the
                     Acceptance Test Period (by electronic mail), specifying the
                     nature of the failure in reasonable detail. Vendor will
                     remove rejected Dedicated Dial-Up Access Ports from service
                     pending further troubleshooting and corrective action. At
                     no additional charge to Customer, Vendor shall use
                     commercially reasonable efforts to repair, replace or
                     otherwise correct the Dial-Up Nonconformity (and any other
                     problems of which it has knowledge) as soon as reasonably
                     practicable after receiving notice from Customer so that
                     the Dedicated Dial-Up Access Ports meet the applicable
                     Acceptance Criteria.

               (ii)  Upon completion of such efforts and Vendor's re-release of
                     Dedicated Dial-Up Access Ports to Customer, Customer shall
                     have an additional [*Material Omitted and Separately Filed
                     Under an Application for Confidential Treatment] business
                     day period to retest the re-delivered Dedicated Dial-Up
                     Access Ports to determine whether the previously reported
                     Dial-Up Nonconformity has been corrected and if such
                     Dedicated Dial-Up Access Ports otherwise then meet the
                     applicable Acceptance Criteria. This process will be
                     repeated as necessary until all Dial-Up Nonconformities are
                     corrected and such Dedicated Dial-Up Access Ports meet the
                     applicable Acceptance Criteria.

               (iii) Notwithstanding Subsection (ii) above, if after [*Material
                     Omitted and Separately Filed Under an Application for
                     Confidential Treatment] attempts for curing Dial-Up
                     Nonconformities, Vendor has not delivered such Dedicated
                     Dial-Up Access Ports conforming to the applicable
                     Acceptance Criteria, then Customer may:

--------------------------------------------------------------------------------
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                       CONFIDENTIAL TREATMENT REQUESTED

                    (1)  allow Vendor to continue to try to correct any Dial-Up
                         Nonconformities;

                    (2)  if mutually agreed upon by the Parties, accept such
                         Dedicated Dial-Up Access Ports in their nonconforming
                         condition and reduce Vendor's charges for such
                         Dedicated Dial-Up Access Ports by a reasonable amount
                         as mutually determined by the Parties that shall
                         reflect the reduced value of such Dedicated Dial-Up
                         Access Ports; or

                    (3)  (A) cancel, in whole or in part, at no cost or
                         liability to Customer the portion of the corresponding
                         Order that does not conform as of a date specified in a
                         written notice of cancellation issued by Customer, and
                         (B) so long as the Dial-Up Nonconformities affect at
                         least[*Material Omitted and Separately Filed Under an
                         Application for Confidential Treatment] ([*Material
                         Omitted and Separately Filed Under an Application for
                         Confidential Treatment]) of the Order, cancel, in whole
                         or in part, at no cost or liability to Customer the
                         unfilled portion of the corresponding Order as of a
                         date specified in a written notice of cancellation
                         issued by Customer. Customer shall have no payment
                         obligations to Vendor with respect to any cancelled
                         portion of an Order.

          (c)  Final Acceptance. Dedicated Dial-Up Access Ports ordered by
               ----------------
               Customer shall be deemed to be accepted (such acceptance the
               "Final Acceptance") only upon the earlier of: (i) receipt by
               Vendor of written notice by Customer certifying that such
               Dedicated Dial-Up Access Ports conform to the applicable
               Acceptance Criteria; or (ii) the expiration of the Dial-Up
               Acceptance Testing Period for such Dedicated Dial-Up Access Ports
               without notice of rejection by Customer. Notwithstanding anything
               to the contrary herein, Final Acceptance of Dedicated Dial-Up
               Access Ports shall only occur in accordance with the terms of
               this Agreement. Use of Dedicated Dial-Up Access Ports for
               business, profit, or any other purpose before Final Acceptance
               shall not constitute Final Acceptance by Customer.

     2.8. Dial-Up Purchase Commitments.
          ----------------------------

          (a)  Dial-Up Purchase Commitments.
               ----------------------------

               The Monthly Targets for Customer's purchase commitments are set
               forth in Exhibit B-1. The minimum commitments specified in
               Exhibit B-1 collectively, and as may be adjusted pursuant to the
               Agreement, shall be referred to as the "Dial-Up Purchase
               Commitment". All Dedicated Dial-Up Access Ports ordered by
               Customer pursuant to an Order shall contribute to Customer's
               satisfaction of the Dial-Up Purchase Commitment. Customer shall
               not be obligated to purchase any Dial-Up Access Services in
               excess of the Dial-Up

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                       CONFIDENTIAL TREATMENT REQUESTED

               Purchase Commitment (as such commitment may be adjusted pursuant
               to the Agreement).

          (b)  Application of Reductions in Purchase Commitments.
               -------------------------------------------------

               In the event that Customer is entitled to a reduction in the
               Dial-Up Purchase Commitment pursuant to the Agreement, each
               commitment described in Subsections (b), (c), (d), and (e) of
               Exhibit B-1 shall be reduced by the amount of such reduction. The
               Parties shall mutually agree upon a reasonable notification
               process with respect to reductions in the Dial-Up Purchase
               Commitment.

          (c)  Substitution of Purchase Commitments Under International
               --------------------------------------------------------
               Agreements.
               ----------

               If Vendor offers Customer or Special Affiliates dial-up access
               services for provision outside of the United States (excluding
               Japan) at market competitive prices and terms:

               (i)  Customer will use commercially reasonable efforts to
                    encourage such Special Affiliates to purchase in the
                    aggregate for all such Special Affiliates [*Material Omitted
                    and Separately Filed Under an Application for Confidential
                    Treatment] Dial-Up Access Ports from Vendor or Vendor's
                    Affiliates at such market competitive prices and terms; and

               (ii) If as of [*Material Omitted and Separately Filed Under an
                    Application for Confidential Treatment] such Special
                    Affiliates have not ordered, committed to order or purchase,
                    or actually purchased, in the aggregate for all such Special
                    Affiliates, [*Material Omitted and Separately Filed Under an
                    Application for Confidential Treatment] Dial-Up Access Ports
                    from Vendor or Vendor's Affiliates at market competitive
                    prices and terms with durations of at least [*Material
                    Omitted and Separately Filed Under an Application for
                    Confidential Treatment], then Customer shall purchase a
                    number of Dedicated Dial-Up Access Ports under this
                    Agreement equal to the difference between [*Material Omitted
                    and Separately Filed Under an Application for Confidential
                    Treatment] Dedicated Dial-Up Access Ports and the actual
                    number of dial-up access ports that such Special Affiliates
                    in the aggregate ordered, committed to order or purchase, or
                    actually ordered from Vendor or Vendor's Affiliates as of
                    such date (as determined utilizing the Normalization
                    Methodology if applicable). Notwithstanding the foregoing,
                    if (1) a Special Affiliate is offered services by a third
                    party similar to the Dial-Up Access Services ordered or
                    purchased pursuant to this Agreement at prices and terms
                    more competitive than those offered by Vendor or Vendor's
                    Affiliates to such Special Affiliate in a country in which
                    Vendor either has operations or has indicated an intent in
                    which to operate, (2) such Special Affiliate, in its sole
                    discretion, requests Vendor to provide Dial-Up Access
                    Services

--------------------------------------------------------------------------------
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<PAGE>

                       CONFIDENTIAL TREATMENT REQUESTED

                    at prices and terms at least as favorable to Special
                    Affiliate as such prices and terms offered by such third
                    party, and (c) Vendor or Vendor's Affiliates declines to
                    provide such services at such prices and terms, then
                    Customer's obligation under this Subsection (c) shall be
                    reduced by the aggregate amount of Dial-Up Access Ports
                    purchased by such Special Affiliate from such third party.

3.   Relocation of dial-Up access services

     Customer shall have the right to direct at any time a change in the
     location in which Dial-Up Access Services are provided within Existing
     Calling Areas (including a reallocation of Dedicated Dial-Up Access Ports
     among locations). In the event that Customer provides Vendor with notice of
     such direction, Vendor shall comply with such direction within a reasonable
     time; provided, however, that (a) any additional reasonable costs incurred
     by Vendor, including any reasonable service termination or service
     activation costs, will be reimbursed by Customer on an Out-of-Pocket
     Expenses basis, (b) with respect to Dial-Up Access Services, Customer shall
     not direct relocation of more than [*Material Omitted and Separately Filed
     Under an Application for Confidential Treatment] Dedicated Dial-Up Access
     Ports in any given calendar month; and (c) such relocation shall result in
     the same approximate weighted distribution of Dedicated Dial-Up Access
     Ports across Existing Calling Areas.

4.   RESALE OF DIAL-UP ACCESS SERVICES

          (a)  Unless otherwise agreed by Customer in writing:

               (i)  Each Dedicated Dial-Up Access Port shall be exclusively
                    available to Customer and its Special Affiliates to whom
                    Vendor is providing Dedicated Dial-Up Services; and

               (ii) Vendor shall not resell or offer to resell any Dedicated
                    Dial-Up Access Port ordered and accepted by Customer;

               provided however, that Vendor may continue to provide access, at
               current levels or levels that are lesser than current levels and
               consistent with Vendor's obligations under section 10 of the
               Original Agreement, as amended, with respect to (A) until (but no
               later than) January 31, 2000, Dedicated Dial-Up Access Ports
               (excluding the approximately [*Material Omitted and Separately
               Filed Under an Application for Confidential Treatment] rotaries)
               to those Vendor customers that are using such Dedicated Dial-Up
               Access Ports as of the Effective Date, and (B) until (but no
               later than) February 29, 2000, the approximately [*Material
               Omitted and Separately Filed Under an Application for
               Confidential Treatment] rotaries to those Vendor customers that
               are using the same as of the Effective Date (such access "Resold
               Dial-Up Access"), subject to Vendor's payment to Customer of
               access royalties calculated pursuant to this Article 4. At no
               time during the Peak Resale Window (as defined below) may access
               that Vendor is permitted to provide to customers pursuant to this
               Subsection (a) exceed [*Material Omitted and Separately Filed
               Under an Application for Confidential Treatment] ([*Material

--------------------------------------------------------------------------------
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<PAGE>

                       CONFIDENTIAL TREATMENT REQUESTED

               Omitted and Separately Filed Under an Application for
               Confidential Treatment] %) of the Dedicated Dial-Up Access Port
               capacity that Vendor is required to provide pursuant to this
               Schedule B.

          (b)  Access royalties payable by Vendor pursuant to Subsection (a) of
               this Article 4 for Resold Dial-Up Access authorized pursuant to
               such Subsection (a) and occurring before January 1, 2000 shall be
               calculated as follows:

               (i)   For each of the first [*Material Omitted and Separately
                     Filed Under an Application for Confidential Treatment]
                     aggregate hours of Resold Dial-Up Access in a calendar
                     month, the applicable access royalty shall be [*Material
                     Omitted and Separately Filed Under an Application for
                     Confidential Treatment].

               (ii)  For each of the first [*Material Omitted and Separately
                     Filed Under an Application for Confidential Treatment]
                     hours of Resold Dial-Up Access in a calendar month in
                     excess of the [*Material Omitted and Separately Filed Under
                     an Application for Confidential Treatment] hours described
                     in Subsection (i) of this Subsection (b), the applicable
                     access royalty shall be [*Material Omitted and Separately
                     Filed Under an Application for Confidential Treatment]
                     cents ($.[*Material Omitted and Separately Filed Under an
                     Application for Confidential Treatment]) per hour per
                     month.

               (iii) For each hour of Resold Dial-Up Access in a calendar month
                     in excess of the [*Material Omitted and Separately Filed
                     Under an Application for Confidential Treatment] aggregate
                     hours described in Subsections (i) and (ii) of this
                     Subsection (b), the applicable access royalty shall be
                     [*Material Omitted and Separately Filed Under an
                     Application for Confidential Treatment] cents ($.[*Material
                     Omitted and Separately Filed Under an Application for
                     Confidential Treatment]) per hour per month.

               The number of hours of Resold Dial-Up Access during the hours
               between 8:00 p.m. local time and midnight local time daily (such
               daily period the "Peak Resale Window") for Resold Dial-Up Access
               occurring before January 1, 2000 shall not exceed [*Material
               Omitted and Separately Filed Under an Application for
               Confidential Treatment] ([*Material Omitted and Separately Filed
               Under an Application for Confidential Treatment]%) of the
               aggregate number of hours of Resold Dial-Up Access, measured
               quarterly, except that the number of hours of Resold Dial-Up
               Access occurring before January 1, 2000 during the Peak Resale
               Window shall not exceed [*Material Omitted and Separately Filed
               Under an Application for Confidential Treatment] percent
               ([*Material Omitted and Separately Filed Under an Application for
               Confidential Treatment]%) for Dedicated Dial-Up Access Ports
               beyond [*Material Omitted and Separately Filed Under an
               Application for Confidential Treatment]. In the event that Vendor
               does not comply with such restriction, Vendor will pay Customer,
               in addition to the access royalties

--------------------------------------------------------------------------------
Network Services Agreement     America Online, Inc./BBN Corporation CONFIDENTIAL
Schedule B                    Schedule B - Page 9
<PAGE>

                       CONFIDENTIAL TREATMENT REQUESTED

               described above, an additional access royalty of [*Material
               Omitted and Separately Filed Under an Application for
               Confidential Treatment] cents ($.[*Material Omitted and
               Separately Filed Under an Application for Confidential
               Treatment]) [*Material Omitted and Separately Filed Under an
               Application for Confidential Treatment] per hour for each hour of
               Resold Dial-Up Access sold in violation of such restriction.

          (c)  Access royalties payable by Vendor pursuant to Subsection (a) of
               this Article 4 for Resold Dial-Up Access authorized pursuant to
               such Subsection (a) and occurring on or after January 1, 2000 but
               before or during February 29, 2000, for each hour of Resold
               Dial-Up Access shall be [*Material Omitted and Separately Filed
               Under an Application for Confidential Treatment] cents
               ($.[*Material Omitted and Separately Filed Under an Application
               for Confidential Treatment]) per hour per month. The number of
               hours of Resold Dial-Up Access during the Peak Resale Window for
               Resold Dial-Up Access occurring on or after January 1, 2000 but
               before February 29, 2000 shall not exceed [*Material Omitted and
               Separately Filed Under an Application for Confidential Treatment]
               percent ([*Material Omitted and Separately Filed Under an
               Application for Confidential Treatment]%) of the aggregate number
               of hours of Resold Dial-Up Access during such period, measured
               quarterly. In the event that Vendor does not comply with such
               restriction, Vendor will pay Customer, in addition to the access
               royalties described in this Subsection (c), an additional access
               royalty of [*Material Omitted and Separately Filed Under an
               Application for Confidential Treatment] cents ($[*Material
               Omitted and Separately Filed Under an Application for
               Confidential Treatment]) [*Material Omitted and Separately Filed
               Under an Application for Confidential Treatment] per hour for
               each hour of Resold Dial-Up Access sold in violation of such
               restriction.

          (d)  For any Resold Dial-Up Access occurring in violation of
               Subsection (a) of this Article 4 with respect to the Vendor
               customers referenced in the proviso of such Subsection (a),
               Vendor shall pay Customer, as its sole and exclusive remedy, an
               amount equal to [*Material Omitted and Separately Filed Under an
               Application for Confidential Treatment] dollars ($[*Material
               Omitted and Separately Filed Under an Application for
               Confidential Treatment]) [*Material Omitted and Separately Filed
               Under an Application for Confidential Treatment] per hour for
               each hour of Resold Dial-Up Access in violation of Subsection (a)
               of this Article 4, and any such violation shall not be deemed to
               be a breach triggering a termination right under Section 13.1(a)
               of the Master Agreement. For any other resale of Dedicated
               Dial-Up Access Ports in violation of Subsection (a) of this
               Article 4, Vendor shall pay to Customer the [*Material Omitted
               and Separately Filed Under an Application for Confidential
               Treatment] per hour charge described in this Subsection, and such
               violation shall also be deemed a material breach entitling
               Customer to terminate the Agreement in accordance with Section
               13.1(a) of the Master Agreement. Vendor shall promptly report to
               Customer any Resold Dial-Up Access occurring in violation of
               Subsection (a) of this Article 4.

--------------------------------------------------------------------------------
Network Services Agreement     America Online, Inc./BBN Corporation CONFIDENTIAL
Schedule B                    Schedule B - Page 10
<PAGE>

                       CONFIDENTIAL TREATMENT REQUESTED

          (e)  Promptly following the end of each of first three calendar months
               after the Effective Date (i.e., December, 1999, and January,
               February 2000), Vendor will provide Customer with a report
               summarizing the aggregate number of hours of Resold Dial-Up
               Access or other Services for such month and the corresponding
               access royalties, if any, payable by Vendor pursuant to this
               Article 4.

5.   TRANSITION PERIOD and limitation of liability

     5.1. Transition Period.
          -----------------

          The Transition Period applicable to Dial-Up Access Services shall be
          equal to three months for each [*Material Omitted and Separately Filed
          Under an Application for Confidential Treatment] Dial-Up Access Ports
          existing as of the effective date of expiration, termination or
          cancellation (but in no event shorter than 12 months).

     5.2. Liability Restrictions.

          (a)  Subject to Subsection (e) of this Section, the liability of
               Vendor to Customer for all damages arising out of or related to
               the Services provided under this Schedule will be limited to, and
               will not exceed, in the aggregate during any calendar year,
               [*Material Omitted and Separately Filed Under an Application for
               Confidential Treatment] percent ([*Material Omitted and
               Separately Filed Under an Application for Confidential
               Treatment]%) of the aggregate amounts paid to Vendor by Customer
               (excluding Out-of-Pocket Expenses) under this Schedule and the
               Original Agreement during the twelve (12) month period preceding
               the date of the event giving rise to such damages. Subject to
               Subsections (c) and (e) of this Section, the liability of Vendor
               to Customer for damages arising out of or related to Services
               provided under this Schedule caused by the acts or omissions of
               third parties beyond the reasonable control of Vendor will be
               further limited and will not exceed, in the aggregate during any
               calendar year, [*Material Omitted and Separately Filed Under an
               Application for Confidential Treatment] Dollars ($[*Material
               Omitted and Separately Filed Under an Application for
               Confidential Treatment]).

          (b)  By way of example and without limitation, in the event that four
               events occur in calendar year 2000, as described below, for which
               Vendor would have liability to Customer under Subsection (a) of
               this Section, then Vendor's liability to Customer for each such
               event would be as follows:

               (i)  An event in March 2000 that is not caused by the acts or
                    omissions of third parties causing Customer damages of $17
                    million, with the preceding twelve month amounts paid of
                    $350 million, the liability of Vendor to Customer for such
                    event would be $[*Material Omitted and Separately Filed
                    Under an Application for Confidential Treatment]; and

               (ii) An event in June 2000 that is caused by the acts or
                    omissions of third parties beyond the reasonable control of
                    Vendor causing Customer

--------------------------------------------------------------------------------
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<PAGE>

                       CONFIDENTIAL TREATMENT REQUESTED

                     damages of $12 million, with the preceding twelve months
                     amounts paid of $375 million, the liability of Vendor to
                     Customer for such event would be $[*Material Omitted and
                     Separately Filed Under an Application for Confidential
                     Treatment] subject to Vendor's obligations set forth in
                     Subsection (c) of this Section; and

               (iii) An event in October 2000 that is not caused by the acts or
                     omissions of third parties causing Customer damages of $15
                     million, with preceding twelve month amounts paid of $400
                     million, the liability of Vendor to Customer for such event
                     would be $[*Material Omitted and Separately Filed Under an
                     Application for Confidential Treatment]; and

               (iv)  An event in December 2000 that is caused by the acts or
                     omissions of third parties beyond the reasonable control of
                     Vendor causing Customer damages of $3 million, with the
                     preceding twelve months amounts paid of $425 million, the
                     liability of Vendor to Customer for such event would be $
                     [*Material Omitted and Separately Filed Under an
                     Application for Confidential Treatment] subject to Vendor's
                     obligations set forth in Subsection (c) of this Section.

          (c)  In the event of any liability of Vendor to Customer for damages
               arising out of or related to Services provided under this
               Schedule caused by the acts or omissions of third parties beyond
               the reasonable control of Vendor, then the Parties agree as
               follows:

               (i)   Vendor agrees to vigorously pursue the recovery of damages
                     against the third party causing the damage, including
                     through negotiations, dispute resolution, or both, to
                     maximize the damages recoverable against such third party;

               (ii)  Vendor agrees to pass through to Customer any amounts that
                     Vendor actually recovers from such third party relating to
                     damages incurred in connection with Services provided to
                     Customer under this Schedule; and

               (iii) Customer agrees that in the event that Vendor has paid any
                     amounts to Customer pursuant to Subsection (a) of this
                     Section prior to the recovery of damages from a third
                     party, that Vendor may reduce the amount of recovery
                     received from such third party by the amount previously
                     paid to Customer in respect of such event causing the
                     damages.

               (iv)  Amounts recovered by Vendor from third parties shall first
                     be passed on to Customer until Customer's full damages are
                     satisfied.

          (d)  IN NO EVENT, WHETHER IN CONTRACT OR IN TORT (INCLUDING BREACH OF
               WARRANTY, NEGLIGENCE AND STRICT LIABILITY IN TORT), SHALL A PARTY
               BE LIABLE TO THE OTHER PARTY FOR INDIRECT OR CONSEQUENTIAL,
               EXEMPLARY, PUNITIVE OR SPECIAL

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<PAGE>

                       CONFIDENTIAL TREATMENT REQUESTED

               DAMAGES EVEN IF SUCH PARTY HAS BEEN ADVISED OF THE POSSIBILITY OF
               SUCH DAMAGES IN ADVANCE.

          (e)  The limitations set forth in Subsection (a) of this Section shall
               not apply with respect to (i) intentional breach by Vendor; (ii)
               damages occasioned by an intentional tort or the gross negligence
               of Vendor; (iii) damages occasioned by Vendor's breach of its
               obligations described in Article 11 (Confidentiality) of the
               Master Agreement, or (iv) claims subject to indemnification
               pursuant to this Agreement (such amounts paid by the indemnitee
               to third parties shall be deemed to be direct damages) other than
               claims subject to the indemnity set forth in Section 15(a) of the
               Master Agreement.

          (f)  Each Party shall have a duty to reasonably mitigate (i.e.,
               minimize) damages for which the other Party is responsible.

6.   DESCRIPTION OF DIAL-UP ACCESS SERVICES

     Dial-Up Access Services shall include the provision of Dial-Up Access and
     all associated fully managed, end-to-end network service functions
     including the following:

     6.1. General Requirements.
          --------------------

          (a)  Vendor shall provide, for each individual Existing Calling Area,
               a unique set of source IP addresses such that member demographics
               can be identified through such source IP addresses. Customer
               shall be provided the source IP addresses prior to use by Vendor
               to provide the Services.

          (b)  Vendor shall acquire and manage IP addresses for all protocols
               utilized by Customer during the Term.

          (c)  Vendor shall provide domain name services, including the
               following:

               (i)   provision of domain name service for Customer;

               (ii)  resolution of domain name service queries to Customer
                     destinations;

               (iii) support of domain name service for Customer service access
                     to the Customer domain and any zones resident on Customer
                     name servers; and

               (iv)  maintenance of domain name service servers.

          (d)  In the event that Customer requests a change to its access
               method(s), hub architecture, or network bandwidth from that which
               is described in this Schedule B (other than a request for
               increased throughput priced pursuant to Section 8.1(c) of this
               Schedule B), Vendor will provide Customer with Vendor's proposed
               increase, if any, to the prices set forth in this Schedule B. To
               the extent that Customer accepts such proposal, Vendor shall
               provide the Dial-Up

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<PAGE>

                       CONFIDENTIAL TREATMENT REQUESTED

               Access Services in accordance with the requested change and
               Vendor's proposal to the extent accepted by Customer.

          (e)  Vendor will utilize GNI for delivery of data traffic to
               Customer's data centers; provided that, in order to provide last
               mile diversity, at Customer's request, for up to [*Material
               Omitted and Separately Filed Under an Application for
               Confidential Treatment] of the GNI last mile capacity to
               Customer's facilities, Customer and Vendor agree to exchange
               local facilities, at no cost to either Party for equivalent
               bandwidth exchanged. The Parties agree to establish a mutually
               acceptable bandwidth exchanging and circuit management process,
               including co-location space, facility access, and helping hands
               where both Parties have local facilities in each geography.

     6.2. Network Engineering.
          -------------------

          Vendor agrees to provide network engineering to address operational
          and long-term planning issues.

     6.3. Operations.
          ----------

          Vendor will provision, staff, and operate a NOC (currently in
          Columbia, Maryland) with dedicated support for Customer and a backup
          NOC at a separate location (such backup NOCs currently located in
          Chantilly, Virginia). The scope of this task will include the
          following Vendor support services for the network:

          (a)  Operation of the NOC and co-located systems with trained and
               qualified personnel on a continuous, 24 hours per day, 7 days per
               week basis;

          (b)  Operation of all NOC equipment, monitoring, and fault isolation
               functions;

          (c)  Coordination of the dispatch of maintenance representatives for
               corrective maintenance activities and recording information in a
               Problem Report ("PR"). Vendor's responsibilities shall include:

               (i)   Initiation of a [*Material Omitted and Separately Filed
                     Under an Application for Confidential Treatment] request,
                     plus recording the time that the call is received by the
                     Vendor maintenance representative;

               (ii)  Upon arrival of the maintenance representative at the site,
                     confirmation by the [*Material Omitted and Separately Filed
                     Under an Application for Confidential Treatment] and
                     recording the [*Material Omitted and Separately Filed Under
                     an Application for Confidential Treatment] with the
                     representative;

               (iii) Upon notification to the NOC by the on-site maintenance
                     representative of [*Material Omitted and Separately Filed
                     Under an Application for Confidential Treatment] access to
                     the [*Material Omitted and Separately Filed Under an
                     Application for Confidential Treatment] shall provide
                     Customer with relevant information; and

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<PAGE>

                       CONFIDENTIAL TREATMENT REQUESTED

               (iv)  Upon restoration of service by the maintenance
                     representative, the NOC shall confirm, with assistance from
                     the maintenance representative, operation of the [*Material
                     Omitted and Separately Filed Under an Application for
                     Confidential Treatment] when [*Material Omitted and
                     Separately Filed Under an Application for Confidential
                     Treatment] are [*Material Omitted and Separately Filed
                     Under an Application for Confidential Treatment] and the
                     reason for the [*Material Omitted and Separately Filed
                     Under an Application for Confidential Treatment];

          (d)  Initiation of [*Material Omitted and Separately Filed Under an
               Application for Confidential Treatment] maintenance of a
               [*Material Omitted and Separately Filed Under an Application for
               Confidential Treatment] coordination of [*Material Omitted and
               Separately Filed Under an Application for Confidential Treatment]
               with support personnel and tracking of problems until resolution
               using a commercially available [*Material Omitted and Separately
               Filed Under an Application for Confidential Treatment] reporting
               software system;

          (e)  Utilization of [*Material Omitted and Separately Filed Under an
               Application for Confidential Treatment] resident in the NOC for:

               (i)   Daily testing of [*Material Omitted and Separately Filed
                     Under an Application for Confidential Treatment] and
                     [*Material Omitted and Separately Filed Under an
                     Application for Confidential Treatment];

               (ii)  Measurements of the usage of each [*Material Omitted and
                     Separately Filed Under an Application for Confidential
                     Treatment] at the frequency or at the times requested by
                     Customer;

               (iii) Monitoring and recording the [*Material Omitted and
                     Separately Filed Under an Application for Confidential
                     Treatment] and [*Material Omitted and Separately Filed
                     Under an Application for Confidential Treatment] and
                     [*Material Omitted and Separately Filed Under an
                     Application for Confidential Treatment];and

               (iv)  Accounting for the disposition of each [*Material Omitted
                     and Separately Filed Under an Application for Confidential
                     Treatment] (e.g., how many [*Material Omitted and
                     Separately Filed Under an Application for Confidential
                     Treatment] how many [*Material Omitted and Separately Filed
                     Under an Application for Confidential Treatment] how many
                     [*Material Omitted and Separately Filed Under an
                     Application for Confidential Treatment] how many [*Material
                     Omitted and Separately Filed Under an Application for
                     Confidential Treatment] subject to Section 8.5(a) of this
                     Schedule B;

          (f)  Providing on-site analyst support, at the NOC utilized to provide
               Dial-Up Access Services, [*Material Omitted and Separately Filed
               Under an Application for Confidential Treatment]. A dedicated
               access number shall be maintained for Customer's exclusive use,
               which shall always be [*Material Omitted and

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                       CONFIDENTIAL TREATMENT REQUESTED

               Separately Filed Under an Application for Confidential
               Treatment]. Analyst support shall include the following:

               (i)   Supporting short-term and long-term problem identification,
                     analysis, and resolution;

               (ii)  Ensuring that proper steps are taken to resolve the
                     problem;

               (iii) Identifying and tracking all software, baseline and
                     patches, deployed in the Vendor Network and NOC platforms;

               (iv)  Supporting the deployment of new software to the Vendor
                     Network, Customer's networks and NOC equipment as
                     coordinated with Customer;

               (v)   Providing support to network provisioning requirements; and

               (vi)  Maintaining a technical library for the NOC.

          (g)  Performing on-call analyst support of the Vendor Network on a
               continuous 24 hour per day, 7 days per week basis. On-call
               analyst personnel respond to urgent requests from the NOC in
               conjunction with the on-site Vendor personnel. Procedures for the
               conduct of network testing are in accordance with those developed
               in conjunction with Customer representatives;

          (h)  Providing operational support to Customer in the area of network
               testing in association with provisioning actions. Such testing
               shall be conducted from the NOC in conjunction with the on-site
               Vendor installation team personnel;

          (i)  Maintaining and providing updates and changes to NOC maps;

          (j)  Maintaining an authorized outage listing for NOC controller use;

          (k)  Acting as Customer's agent in network security matters on a
               day-to-day basis as directed by Customer in accordance with
               commercially reasonable practices, and making recommendations for
               improvements;

          (l)  Using commercial teleconferencing facilities in the resolution of
               network problems, escalation of problems, and planning
               activities;

          (m)  Providing electronic mail service support for the NOC [*Material
               Omitted and Separately Filed Under an Application for
               Confidential Treatment];

          (n)  Providing a facsimile service resident in the NOC equipment;

          (o)  Subject to Section 8.5(a) of this Schedule B, delivering the
               following reports to Customer-designated representatives:

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                       CONFIDENTIAL TREATMENT REQUESTED

               (i)   [*Material Omitted and Separately Filed Under an
                     Application for Confidential Treatment] reports;

               (ii)  [*Material Omitted and Separately Filed Under an
                     Application for Confidential Treatment] summaries of the
                     [*Material Omitted and Separately Filed Under an
                     Application for Confidential Treatment];

               (iii) [*Material Omitted and Separately Filed Under an
                     Application for Confidential Treatment] report;

               (iv)  [*Material Omitted and Separately Filed Under an
                     Application for Confidential Treatment] statistics;

               (v)   [*Material Omitted and Separately Filed Under an
                     Application for Confidential Treatment] statistics; and

               (vi)  [*Material Omitted and Separately Filed Under an
                     Application for Confidential Treatment] data as required to
                     [*Material Omitted and Separately Filed Under an
                     Application for Confidential Treatment] problems;

               Customer may request additional reports that assist in improving
               the quality of the Vendor Network and Customer's networks. Vendor
               will provide these additional reports, or the raw data, subject
               to technical reasonableness.

     6.4. Network Support Organization.
          ----------------------------

          Vendor shall structure the provision of Services in a manner that will
          enable Vendor to rapidly build out its networks and deliver quality
          Services.

          (a)  Program Management: Vendor's program management group shall
               ------------------
               responsible for the management of the Services as a whole. The
               program management team shall be led by a program executive who
               has direct and immediate access to the senior management of
               Vendor and a program manager who reports to such program
               executive. The program management team shall be (i) the primary
               point of contact between Vendor and Customer and shall coordinate
               the activity of all functional groups within Vendor and (ii)
               responsible for project and financial management of the Services.

          (b)  Engineering: Vendor shall maintain an network engineering group
               -----------
               that shall handle the technical aspects of the Services,
               resolution of problems escalated by the NOC, planning for future
               network expansion, and improvement of performance and process.
               Such engineering group shall interact directly with Customer and
               the NOC.

          (c)  Deployment: Vendor shall maintain a deployment team consisting of
               ----------
               field engineers and technicians, as well as others who have
               experience dealing directly with telcos, preparing sites, and
               installing equipment. Part of this team

--------------------------------------------------------------------------------
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                       CONFIDENTIAL TREATMENT REQUESTED

               will be based at Vendor's facilities to coordinate activities and
               provide support for installers.

          (d)  Operations: Vendor's NOC shall handle the operation and
               ----------
               maintenance of the Vendor Network. The NOC will be connected to
               Customer's central facilities, including a direct telephone link
               to the Customer operations center. The NOC's monitoring
               capability shall be set up to detect and correct most network
               problems before they are visible to Customer or its customers.

     6.5. Other Services.
          --------------

          (a)  The NOC shall direct maintenance activities based on input from
               the monitoring systems and Customer. Vendor shall handle a large
               majority of repair tasks over the telephone with technicians at
               the Dial-Up Access Port equipment locations by storing Dial-Up
               Access subsystems at these locations, establishing working
               agreements with the service providers at these locations, and by
               providing written procedures. When it is necessary to send
               technicians to deal with problems, Vendor shall use its existing
               infrastructure of satellite offices and field engineers.

          (b)  Vendor agrees not to restrict Customer's dial-up traffic to and
               from Customer unless requested to do so by Customer or required
               to do so by court order or applicable law.

          (c)  The Parties shall use commercially reasonable efforts to
               [*Material Omitted and Separately Filed Under an Application for
               Confidential Treatment] information sent to each other and to
               [*Material Omitted and Separately Filed Under an Application for
               Confidential Treatment] and withdrawal of [*Material Omitted and
               Separately Filed Under an Application for Confidential Treatment]
               equipment.

          (d)  Vendor shall announce Customer [*Material Omitted and Separately
               Filed Under an Application for Confidential Treatment]
               information at [*Material Omitted and Separately Filed Under an
               Application for Confidential Treatment] as required by Customer.

          (e)  Vendor shall reasonably coordinate with Customer regarding any
               maintenance activity.

     6.6. Telephone Numbers Used to Provide Dial-Up Access Services.
          ---------------------------------------------------------

          (a)  Upon (i) the request of Customer from time to time, (ii)
               expiration of the Agreement or Schedule B of the Agreement, or
               (iii) any termination of the Agreement or Schedule B of the
               Agreement, Vendor shall provide Customer with a complete listing
               of telephone numbers used to provide Dial-Up Access Services.
               Ownership of such telephone number shall be governed by the
               Master Agreement. Vendor shall not provide such telephone numbers
               for use by Vendor (except to the extent necessary for Vendor to
               provide the Dial-Up

--------------------------------------------------------------------------------
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<PAGE>

                       CONFIDENTIAL TREATMENT REQUESTED

               Access Services) or any third party (other than third parties
               designated by Customer from time to time) without prior written
               permission from Customer.

          (b)  For each telephone number to a Dial-Up Access Port equipment
               location, and upon the decommissioning of corresponding Dial-Up
               Access Services and upon the expiration or termination of this
               Schedule B or the Agreement:

               (i)  If such telephone number is provided by Vendor or an
                    Affiliate of Vendor, Vendor shall, to the extent legally
                    permitted to do so, obtain the rights necessary for Customer
                    or a designee of Customer to utilize such telephone number
                    to provide services upon any expiration or termination of
                    this Schedule B; and

               (ii) If such telephone number is provided by an entity other than
                    by Vendor or an Affiliate of Vendor, then Vendor shall use
                    commercially reasonable efforts to obtain the rights
                    necessary for Customer or a designee of Customer to utilize
                    such telephone number to provide services upon any
                    expiration or termination of this Schedule B.

          (c)  Vendor shall provide Customer with no less than thirty (30) days
               advance written notice before it changes any telephone number to
               a Dial-Up Access Port equipment location. Vendor shall not
               utilize any new telephone number to provide Dial-Up Access
               Services until Customer has accepted such telephone number in the
               manner described in Section 2.7 of this Schedule B. In the event
               of any such change, (i) Vendor shall provide Dial-Up Access
               Services using both the original telephone number and the new
               telephone number for a minimum of seven (7) calendar days after
               acceptance by Customer of the new number, and (ii) the total
               number of Dedicated Dial-Up Access Ports utilized for both
               telephone numbers shall at all times be equal to or greater than
               the total number of Dedicated Dial-Up Access Ports utilized for
               the original telephone number.

7.   SERVICE LEVELS FOR DIAL-UP ACCESS SERVICES

     This Article 7 sets forth the Service Levels that Vendor is required to
     meet or exceed pursuant to Article 7 of the Master Agreement, certain
     remedies for Vendor's failure to achieve the Service Levels, as well as
     terms and conditions with respect to Service Level reporting and
     adjustment. For each of the Service Levels set forth in this Article 7,
     scheduled maintenance by Vendor (or a third party) coordinated with
     Customer pursuant to Section 6.5(a) of this Schedule B will be excluded
     from the Service Level performance calculations.

     7.1. Service Levels.
          --------------

          Dial-Up Access Services provided under the Agreement shall be
          implemented with redundancy. In addition, any Dial-Up Access Port
          equipment locations in which Vendor provides Services other than the
          [*Material Omitted and Separately Filed Under an Application for
          Confidential Treatment] equipment locations existing as of the
          Effective Date [*Material Omitted and Separately Filed Under an
          Application for Confidential Treatment] sufficient to ensure
          [*Material Omitted and Separately Filed Under an

--------------------------------------------------------------------------------
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<PAGE>

                       CONFIDENTIAL TREATMENT REQUESTED

          Application for Confidential Treatment] in the event of a [*Material
          Omitted and Separately Filed Under an Application for Confidential
          Treatment]

          (a)  Vendor Network Availability.
               ---------------------------

               (i)   "Network Availability" shall mean the percentage of the
                     time that each access device used to provide Dial-Up Access
                     Services is reachable through the Vendor Network from the
                     Customer's front-end hosts and vice-versa.

               (ii)  The Service Level applicable to Network Availability shall
                     be as follows: Network Availability for each calendar month
                     shall exceed [*Material Omitted and Separately Filed Under
                     an Application for Confidential Treatment] percent
                     ([*Material Omitted and Separately Filed Under an
                     Application for Confidential Treatment] %). Vendor's
                     performance relative to such Service Level shall be
                     reported by Vendor on a monthly basis for each calendar
                     month.

               (iii) In the event that Network Availability is below [*Material
                     Omitted and Separately Filed Under an Application for
                     Confidential Treatment] percent ([*Material Omitted and
                     Separately Filed Under an Application for Confidential
                     Treatment] %) as measured in either [*Material Omitted and
                     Separately Filed Under an Application for Confidential
                     Treatment] or on a [*Material Omitted and Separately Filed
                     Under an Application for Confidential Treatment], such
                     event shall constitute a material breach of the Agreement.

          (b)  Average [*Material Omitted and Separately Filed Under an
               Application for Confidential Treatment] Percentage

               (i)   [*Material Omitted and Separately Filed Under an
                     Application for Confidential Treatment] Percentage for any
                     day of a calendar month is calculated as (A) the aggregate
                     number of [*Material Omitted and Separately Filed Under an
                     Application for Confidential Treatment], during such
                     calendar day that result in a [*Material Omitted and
                     Separately Filed Under an Application for Confidential
                     Treatment] divided by (B) the aggregate number of such
                     [*Material Omitted and Separately Filed Under an
                     Application for Confidential Treatment] during such
                     calendar day. "Average [*Material Omitted and Separately
                     Filed Under an Application for Confidential Treatment]
                     Percentage" for any calendar month shall mean the
                     percentage-point aggregate of the [*Material Omitted and
                     Separately Filed Under an Application for Confidential
                     Treatment] Percentages calculated for each day of such
                     month, divided by the number of calendar days in such
                     month.

               (ii)  The Service Level applicable to Average [*Material Omitted
                     and Separately Filed Under an Application for Confidential
                     Treatment] Percentage shall be as follows: The Average
                     [*Material Omitted and Separately Filed Under an
                     Application for Confidential Treatment]

--------------------------------------------------------------------------------
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<PAGE>

                     CONFIDENTIAL TREATMENT REQUESTED

                     Percentage for each calendar month of the Term shall not be
                     greater than [*Material Omitted and Separately Filed Under
                     an Application for Confidential Treatment] percentage
                     points above the corresponding [*Material Omitted and
                     Separately Filed Under an Application for Confidential
                     Treatment] for such month. Customer will provide reporting
                     to Vendor summarizing Vendor's performance with respect to
                     this Service Level.

               (iii) In the event that Vendor fails to meet the Service Level
                     corresponding to Average [*Material Omitted and Separately
                     Filed Under an Application for Confidential Treatment]
                     Percentage for each of [*Material Omitted and Separately
                     Filed Under an Application for Confidential Treatment]
                     calendar months, such [*Material Omitted and Separately
                     Filed Under an Application for Confidential Treatment]
                     shall constitute [*Material Omitted and Separately Filed
                     Under an Application for Confidential Treatment]. In the
                     event that Vendor fails to meet the Service Level
                     corresponding to Average [*Material Omitted and Separately
                     Filed Under an Application for Confidential Treatment]
                     Percentage by at least [*Material Omitted and Separately
                     Filed Under an Application for Confidential Treatment]
                     percentage points above the corresponding [*Material
                     Omitted and Separately Filed Under an Application for
                     Confidential Treatment] for each of [*Material Omitted and
                     Separately Filed Under an Application for Confidential
                     Treatment], then Customer may, at its option and in its
                     sole discretion, [*Material Omitted and Separately Filed
                     Under an Application for Confidential Treatment]. Vendor
                     shall be relieved of its obligation to meet the Service
                     Level applicable to Average [*Material Omitted and
                     Separately Filed Under an Application for Confidential
                     Treatment] Percentage to the extent that such failure is
                     caused by a significant change in the [*Material Omitted
                     and Separately Filed Under an Application for Confidential
                     Treatment] over the same period.

          (c)  Call Blocking.
               -------------

               (i)  "Call Blocking Event" means the occurrence of a Blocked Call
                    during the time when any Dedicated Dial-Up Access Port
                    corresponding to a telephone number is not being utilized.
                    "Blocked Call" means an attempted call, by Customer
                    equipment to a telephone number used to provide the Dial-Up
                    Access Services, to a Dedicated Dial-Up Access Port that
                    results in the return of a busy signal or other failure to
                    connect. Vendor shall provide to Customer reporting each
                    calendar day of each calendar month showing the usage of all
                    Dedicated Dial-Up Access Ports corresponding to each
                    telephone number used to provide Dial-Up Access Services in
                    [*Material Omitted and Separately Filed Under an Application
                    for Confidential Treatment] increments. Using such reporting
                    and other information, Customer will measure daily the
                    number of Call Blocking Events; provided, however, that no
                    Dedicated Dial-Up Access Port shall account for more than
                    one Call Blocking

--------------------------------------------------------------------------------
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<PAGE>

                       CONFIDENTIAL TREATMENT REQUESTED

                     Event until Vendor reports such Dedicated Dial-Up Access
                     Port is available or such Dedicated Dial-Up Access Port
                     actually becomes available.

               (ii)  The Service Level applicable to Call Blocking Events shall
                     be as follows: For any Call Blocking Event, Vendor shall
                     remedy the circumstances causing such event within
                     [*Material Omitted and Separately Filed Under an
                     Application for Confidential Treatment] hours after
                     Customer's notification of the same. Vendor's performance
                     relative to such Service Level shall be reported by
                     Customer on a monthly basis for each calendar month.

               (iii) In the event that the Vendor does not satisfy the Service
                     Level set forth in Subsection (ii) of this Subsection (c)
                     (i.e., the causes of the Call Blocking Event are not
                     remedied pursuant to Subsection (ii) of this Subsection
                     (c)), then Customer, as its sole and exclusive remedy,
                     shall [*Material Omitted and Separately Filed Under an
                     Application for Confidential Treatment] for the [*Material
                     Omitted and Separately Filed Under an Application for
                     Confidential Treatment] equal to (A) the aggregate number
                     of [*Material Omitted and Separately Filed Under an
                     Application for Confidential Treatment] for each[*Material
                     Omitted and Separately Filed Under an Application for
                     Confidential Treatment] that were not being utilized during
                     the period between the time that a [*Material Omitted and
                     Separately Filed Under an Application for Confidential
                     Treatment], multiplied by (B) [*Material Omitted and
                     Separately Filed Under an Application for Confidential
                     Treatment] for the corresponding [*Material Omitted and
                     Separately Filed Under an Application for Confidential
                     Treatment] occurred or persisted [*Material Omitted and
                     Separately Filed Under an Application for Confidential
                     Treatment].

          (d)  Training Failure Event Percentage.
               ---------------------------------

               (i)   "Training Failure Event" means, for any call by Customer
                     equipment to a Dedicated Dial-Up Access Port, the failure
                     of the modem devices utilized for such call to properly
                     complete modem handshake and negotiate a communications
                     session. "Training Failure Event Percentage" for any
                     telephone number means (A) the aggregate number of Training
                     Failure Events occurring during a calendar day for such
                     number, divided by (B) the aggregate number of calls by
                     Customer equipment to a Dedicated Dial-Up Access Port
                     corresponding to such telephone number during such day,
                     with the result expressed as a percentage. Vendor will
                     measure the occurrence of Training Failure Events, and will
                     calculate the Training Failure Event Percentage for each
                     day.

               (ii)  The Service Level applicable to Training Failure Event
                     Percentage shall be as follows: The Training Failure Event
                     Percentage for each calendar day of the Term shall be less
                     than [*Material Omitted and Separately

--------------------------------------------------------------------------------
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<PAGE>

                       CONFIDENTIAL TREATMENT REQUESTED

                    Filed Under an Application for Confidential Treatment] for
                    such day.

          (e)  Ineffective Call Percentage.
               ---------------------------

               (i)   "Ineffective Call Percentage" means, for any calendar
                     month, the amount calculated as (A) the aggregate number of
                     calls that are successfully placed to an access device used
                     to provide Dial-Up Access Services but that are not able to
                     connect to Customer's front end host other than as a result
                     of problems with Customer's front-end host or Customer-
                     managed equipment, divided by (B) the aggregate number of
                     calls that are successfully placed to an access device used
                     to provide Dial-Up Access Services.

               (ii)  The Service Level applicable to Ineffective Call Percentage
                     shall be as follows: Ineffective Call Percentage for each
                     calendar month shall not exceed [*Material Omitted and
                     Separately Filed Under an Application for Confidential
                     Treatment] percent ([*Material Omitted and Separately Filed
                     Under an Application for Confidential Treatment]%).
                     Vendor's performance relative to such Service Level shall
                     be reported by Vendor on a daily basis.

          (f)  Customer Reported Problems.
               --------------------------

               (i)   "Customer Reported Problem" means any problem, reported by
                     a user of Customer's services, that is related to the Dial-
                     Up Access Services. "Customer Reported Problem Average" for
                     any calendar month means the average number of Customer
                     Reported Problems per one million user sessions during such
                     month.

               (ii)  The Service Level applicable to Customer Reported Problem
                     Average shall be as follows: The Customer Reported Problem
                     Average for each calendar month of the Term shall be less
                     than the corresponding [*Material Omitted and Separately
                     Filed Under an Application for Confidential Treatment] for
                     such month. Vendor's performance relative to such Service
                     Level shall be reported by Customer on a monthly basis for
                     each calendar month.

          (g)  Monthly Abnormal Disconnect Percentage.
               --------------------------------------

               (i)   "Daily Abnormal Disconnect Percentage" means, for each
                     calendar day of the Term, the amount calculated as (A) the
                     aggregate number of disconnected Dedicated Dial-Up Port
                     sessions during such day that are not initiated by a user
                     logoff sequence and that are caused by a problem with
                     respect to the Dial-Up Access Port or Vendor Network
                     between the access device used to provide Dial-Up Access
                     Services and the Vendor-managed Customer hub routers at
                     Customer's facilities, divided by (B) the aggregate number
                     of all Dedicated Dial-Up Port sessions commencing during
                     such calendar day, with the result expressed as a

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<PAGE>

                       CONFIDENTIAL TREATMENT REQUESTED

                     percentage. "Monthly Abnormal Disconnect Percentage" means,
                     for each calendar month of the Term, the amount calculated
                     as (x) the percentage-point aggregate of the Daily Abnormal
                     Disconnect Percentages for such calendar month, divided by
                     (y) the aggregate number of calendar days in such calendar
                     month.

               (ii)  The Service Level applicable to Monthly Abnormal Disconnect
                     Percentage shall be as follows: Monthly Abnormal Disconnect
                     Percentage during a calendar month shall be less than
                     [*Material Omitted and Separately Filed Under an
                     Application for Confidential Treatment] percentage points
                     above the corresponding [*Material Omitted and Separately
                     Filed Under an Application for Confidential Treatment] for
                     such month. Vendor's performance relative to such Service
                     Level shall be reported by Customer on a monthly basis for
                     each calendar month.

               (iii) In the event that Vendor fails to meet the Service Level
                     corresponding to Monthly Abnormal Disconnect Percentage for
                     each of [*Material Omitted and Separately Filed Under an
                     Application for Confidential Treatment] such failure shall
                     constitute [*Material Omitted and Separately Filed Under an
                     Application for Confidential Treatment]. In the event that
                     Vendor fails to meet the Service Level corresponding to
                     Monthly Abnormal Disconnect Percentage by at least
                     [*Material Omitted and Separately Filed Under an
                     Application for Confidential Treatment] percentage points
                     above the corresponding [*Material Omitted and Separately
                     Filed Under an Application for Confidential Treatment] for
                     each of [*Material Omitted and Separately Filed Under an
                     Application for Confidential Treatment] then Customer may,
                     at its option and its sole discretion, [*Material Omitted
                     and Separately Filed Under an Application for Confidential
                     Treatment] for this [*Material Omitted and Separately Filed
                     Under an Application for Confidential Treatment]. Vendor
                     shall be relieved of its obligation to meet the Service
                     Level applicable to Monthly Abnormal Disconnect Percentage
                     to the extent that such failure is caused by [*Material
                     Omitted and Separately Filed Under an Application for
                     Confidential Treatment] Average over the same period.

          (h)  Packet Loss Percentage.
               ----------------------

               (i)   "Packet Loss Percentage" means, for a calendar month, the
                     quantity calculated as (A) the aggregate number of data
                     packets dropped from the Vendor Network between the
                     Ethernet interface on an access device and the Vendor-
                     managed Customer hub routers during such month, divided by
                     (B) the aggregate number of all data packets introduced
                     into the Vendor Network between the Ethernet interface on
                     an access device and the Vendor-managed Customer hub
                     routers during such calendar month, the result expressed as
                     a percentage.

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<PAGE>

                       CONFIDENTIAL TREATMENT REQUESTED

               (ii)  The Service Level applicable to Packet Loss Percentage
                     shall be as follows: Packet Loss Percentage for each
                     calendar month of the Term shall be less than [*Material
                     Omitted and Separately Filed Under an Application for
                     Confidential Treatment] percent ([*Material Omitted and
                     Separately Filed Under an Application for Confidential
                     Treatment]%) for such month. Vendor's performance relative
                     to such Service Level shall be reported by Vendor on a
                     monthly basis.

          (i)  Latency.
               -------

               (i)   "Latency" means the time interval between (A) the moment
                     when a ping is sent by Customer's PC equipment to a Dial-Up
                     Access Port equipment location, until (B) the moment when
                     the ping is returned to such PC equipment.

               (ii)  The Service Level applicable to Latency shall be as
                     follows: Average Latency for a calendar month shall be less
                     than the corresponding [*Material Omitted and Separately
                     Filed Under an Application for Confidential Treatment] for
                     such month. Vendor's performance relative to such Service
                     Level shall be reported by Customer on a monthly basis for
                     each calendar month.

          (j)  Time to Respond and Time to Restore Service Levels.
               --------------------------------------------------

               (i)   "Time to Respond" means the elapsed time between (i) the
                     time that Customer reports a problem to Vendor with respect
                     to the Services (or the time that Vendor otherwise becomes
                     aware of such a problem), until (ii) the moment that Vendor
                     notifies appropriate Customer personnel of such problem and
                     of those efforts being undertaken by Vendor to resolve such
                     problem. "Mean Time to Respond" for a calendar month shall
                     mean the average of all times corresponding to Time To
                     Respond during such calendar month. "Time to Restore" means
                     the elapsed time between (i) the time that Customer reports
                     a problem to Vendor with respect to the Services (or the
                     time that Vendor otherwise becomes aware of such a
                     problem), until (ii) the moment that the affected Services
                     are restored to normal operations in accordance with
                     applicable Service Levels, Acceptance Criteria and
                     Specifications. "Mean Time to Restore" for a calendar month
                     shall mean the average of all times corresponding to Time
                     To Repair during such calendar month. "Mean Maximum Time to
                     Restore" for a calendar month shall mean the average of all
                     of the maximum times corresponding to [*Material Omitted
                     and Separately Filed Under an Application for Confidential
                     Treatment] during such [*Material Omitted and Separately
                     Filed Under an Application for Confidential Treatment] plus
                     the [*Material Omitted and Separately Filed Under an
                     Application for Confidential Treatment]. Vendor will not
                     close any problem ticket associated with a particular
                     problem until the appropriate Customer

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<PAGE>

                       CONFIDENTIAL TREATMENT REQUESTED

                    representative and a Vendor representative agree that such
                    problem ticket may be closed.

               (ii) The Service Levels applicable to Mean Time to Respond and
                    Mean Time to Restore shall be as follows:

                    (1)  Mean Time to Respond for each calendar month shall be
                         less than [*Material Omitted and Separately Filed Under
                         an Application for Confidential Treatment] minutes;

                    (2)  Mean Time to Restore for each calendar month shall be
                         less than or equal to [*Material Omitted and Separately
                         Filed Under an Application for Confidential Treatment]
                         minutes;

                    (3)  Mean Maximum Time to Restore for each calendar month
                         shall be less than [*Material Omitted and Separately
                         Filed Under an Application for Confidential Treatment]
                         hours.

                    Vendor's performance relative to the foregoing Service
                    Levels shall be reported by Vendor on a monthly basis for
                    each calendar month.

     7.2. Failure to Perform.
          ------------------

          If Vendor fails to meet any Service Level, Vendor shall (a) promptly
          notify Customer of such failure (unless Customer first discovered and
          notified Vendor of such failure), (b) investigate and report on the
          causes of the failure; (c) advise Customer, as and to the extent
          requested by Customer, of the status of remedial efforts being
          undertaken with respect to such failure; (d) take commercially
          reasonable efforts to correct the failure, and begin meeting the
          Service Levels; and (e) take appropriate preventive measures to
          minimize the likelihood of the failure recurring. Notwithstanding the
          foregoing, Vendor's failure to use commercially reasonable efforts to
          meet or correct Service Level failures with respect to the [*Material
          Omitted and Separately Filed Under an Application for Confidential
          Treatment] in and of itself shall not constitute a breach of the
          Agreement. With respect to those Service Levels for which Vendor's
          performance is measured against [*Material Omitted and Separately
          Filed Under an Application for Confidential Treatment], Vendor shall
          not be deemed in breach of such Service Levels to the extent that
          Customer uses [*Material Omitted and Separately Filed Under an
          Application for Confidential Treatment] services provided by other
          [*Material Omitted and Separately Filed Under an Application for
          Confidential Treatment] with respect to such [*Material Omitted and
          Separately Filed Under an Application for Confidential Treatment] in
          such a manner that treats [*Material Omitted and Separately Filed
          Under an Application for Confidential Treatment] than similarly
          [*Material Omitted and Separately Filed Under an Application for
          Confidential Treatment] with respect to the calculation of [*Material
          Omitted and Separately Filed Under an Application for Confidential
          Treatment] relative to the calculation of the [*Material Omitted and
          Separately Filed Under an Application for Confidential Treatment].

     7.3. Reporting.
          ---------

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Schedule B                   Schedule B - Page 26
<PAGE>

                       CONFIDENTIAL TREATMENT REQUESTED

          Vendor shall provide Customer with the following reports, in a
          detailed format reasonably satisfactory to Customer:

          (a)  Usage Reports, including:

               (i)  Daily reports on [*Material Omitted and Separately Filed
                    Under an Application for Confidential Treatment] by
                    [*Material Omitted and Separately Filed Under an Application
                    for Confidential Treatment] by [*Material Omitted and
                    Separately Filed Under an Application for Confidential
                    Treatment] and

               (ii) Daily reports on percentage of ineffective calls; and

          (b)  Daily reports on [*Material Omitted and Separately Filed Under an
               Application for Confidential Treatment] including [*Material
               Omitted and Separately Filed Under an Application for
               Confidential Treatment] and [*Material Omitted and Separately
               Filed Under an Application for Confidential Treatment].

          In addition, upon Customer's request, Vendor shall provide Customer
          with [*Material Omitted and Separately Filed Under an Application for
          Confidential Treatment] and other [*Material Omitted and Separately
          Filed Under an Application for Confidential Treatment] information for
          [*Material Omitted and Separately Filed Under an Application for
          Confidential Treatment] that are utilized to provide [*Material
          Omitted and Separately Filed Under an Application for Confidential
          Treatment] under this Schedule B. In addition, for all other
          components of the Vendor Network that are utilized to provide Dial-Up
          Access Services under this Schedule B, Vendor shall provide to
          Customer a daily report covering the [*Material Omitted and Separately
          Filed Under an Application for Confidential Treatment] as such data is
          collected by Vendor. In the event of a Network outage, Vendor will
          work cooperatively with Customer to share additional SNMP data which
          may be pertinent to the analysis and resolution of any such outage.

     7.4. Meetings.
          --------

          Vendor and Customer shall hold weekly meetings at Customer's site or
          via telephone conference call (unless otherwise requested by Customer)
          to assess Vendor's performance under this Schedule B. During emergency
          situations, meetings will be held at least on a daily basis.

     7.5. Periodic Review of Service Levels.
          ---------------------------------

          As requested by Customer or Vendor, Customer and Vendor shall review
          the Service Levels described in this Schedule B and shall make
          mutually agreed-upon adjustments to them as appropriate to reflect
          performance capabilities associated with advances in the technology
          and methods used to provide the Dial-Up Access Services.

8.   Pricing

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Network Services Agreement     America Online, Inc./BBN Corporation CONFIDENTIAL
Schedule B                   Schedule B - Page 27
<PAGE>

                       CONFIDENTIAL TREATMENT REQUESTED

     This Article 8 describes the methodologies for calculating the charges
     under this Schedule B and relating pricing terms and conditions. The
     charges calculated pursuant to this Schedule B, and any other charges
     expressly set forth in the Master Agreement, shall fully compensate Vendor
     for the provision of the Dial-Up Access Services.

     8.1. Pricing for Dial-Up Access Services.
          -----------------------------------

          (a)  Monthly EDAP Charge.
               -------------------

               (i)  The monthly recurring charge (such charge, as may be
                    adjusted pursuant to the Agreement, the "Monthly EDAP
                    Charge") for one (1) Dedicated Dial-Up Access Port
                    corresponding to the first [*Material Omitted and Separately
                    Filed Under an Application for Confidential Treatment]
                    Dedicated Dial-Up Access Ports of the Dial-Up Purchase
                    Commitment only (such port an "Existing Dedicated Dial-Up
                    Access Port") shall be set at the Existing DAP Market Price,
                    as set forth in Exhibit B-2, and shall be automatically
                    reduced according to the schedule set forth in Exhibit B-2.
                    In addition, the Monthly EDAP Charge may be further reduced
                    as provided in this Article 8 of this Schedule B. The
                    Parties acknowledge that the Monthly EDAP Charge described
                    in the first sentence of Article 2 of Exhibit B-2 shall
                    apply retroactively to October 1, 1999, and Vendor shall
                    provide Customer with a refund of any amounts paid for the
                    corresponding Dial-Up Access Services in excess of such
                    price under the Original Agreement.

               (ii) Following a review of the applicable leases (but in no event
                    later than 45 days after the Effective Date), Vendor shall
                    inform Customer as to the extent to which it desires to (1)
                    assume the operating leases for certain modems, racks and
                    cables for the Existing Dedicated Dial-Up Access Ports
                    leased by Customer (collectively the "Leased Items"), and
                    (2) purchase certain modems, racks and cables for the
                    Existing Dedicated Dial-Up Access Ports owned by Customer
                    (collectively, the "Owned Items"). To the extent that the
                    Parties agree, the Parties shall enter into an amendment
                    under which (A) Vendor shall assume the operating leases for
                    the Leased Items, subject to the terms of such leases and to
                    the rights of third parties in such Leased Items, and (B)
                    Customer shall pass to Vendor title for the Owned Items
                    pursuant to economic terms to be mutually agreed upon,
                    subject to Customer's rights in such equipment. Such
                    amendment shall reflect that, with respect to Vendor's
                    assumption of the leases of the Leased Items, Customer will,
                    on a pass-through expense basis (i.e., without markup), pay
                    leasing costs as and when required under the terms of the
                    leases for the Leased Items. Such amendment shall also
                    reflect that any cost savings achieved by Vendor with
                    respect to leasing and capital costs for the Leased Items
                    will be shared equally between Customer and Vendor. If
                    Vendor decides not to assume the leases for the Leased
                    Items, the rights and obligations of the Parties with
                    respect to the Leased Items shall be as described in the
                    Original Agreement. If Vendor decides not to purchase the
                    Owned

--------------------------------------------------------------------------------
Network Services Agreement     America Online, Inc./BBN Corporation CONFIDENTIAL
Schedule B                   Schedule B - Page 28
<PAGE>

                    Items, Customer shall continue to bear the actual capital
                    costs of the Owned Items in accordance with the terms of the
                    Original Agreement.

          (b)  Monthly DAP Charge.
               ------------------

               The monthly recurring charge (such charge, as may be reduced
               pursuant to the Agreement, the "Monthly DAP Charge") for one (1)
               Dedicated Dial-Up Access Port other than an Existing Dedicated
               Dial-Up Access Port shall be set at the DAP Initial Market Price,
               as set forth in Exhibit B-2, and shall be automatically reduced
               according to the schedule set forth in Exhibit B-2. In addition,
               the Monthly DAP Charge may be further reduced as provided in this
               Article 8 of Schedule B. The Monthly DAP Charge shall fully
               compensate Vendor for the provision of the corresponding Dial-Up
               Access Services (including all capital costs of providing the
               corresponding Dial-Up Access Services (excluding hub routers
               resident at Customer's data centers)).

          (c)  Additional Bandwidth.
               --------------------

               For each additional [*Material Omitted and Separately Filed Under
               an Application for Confidential Treatment] bps of average
               bandwidth available at peak per user outbound (and [*Material
               Omitted and Separately Filed Under an Application for
               Confidential Treatment] bps inbound) per Dedicated Dial-Up Access
               Port that Customer requests Vendor to provide hereunder, Vendor
               shall provide such additional bandwidth at a charge to Customer
               that is no greater than [*Material Omitted and Separately Filed
               Under an Application for Confidential Treatment] ($[*Material
               Omitted and Separately Filed Under an Application for
               Confidential Treatment]) per Dedicated Dial-Up Access Port per
               month for each additional [*Material Omitted and Separately Filed
               Under an Application for Confidential Treatment] bps of such
               bandwidth.

     8.2. Decommissioning of Dedicated Dial-Up Access Ports.
          -------------------------------------------------

          (a)  Beginning [*Material Omitted and Separately Filed Under an
               Application for Confidential Treatment], Customer may
               decommission Dedicated Dial-Up Access Ports that either
               contribute to the satisfaction of the Dial-Up Purchase Commitment
               or to Customer's satisfaction of its obligation described in
               Section 2.8(c)(ii) of this Schedule B, without liability, subject
               to the following:

               (i)  Customer will provide one hundred twenty (120) days prior
                    written notice of the calling areas in which Dedicated
                    Dial-Up Access Ports are to be decommissioned, as well as
                    the associated quantities of Dedicated Dial-Up Access Ports
                    to be decommissioned in each such area;

               (ii) the Vendor Decom Share for a calendar quarter shall not (in
                    the cumulative and not more than a de minimis amount) exceed
                    the Other Vendors' Decom Share for such quarter;

--------------------------------------------------------------------------------
Network Services Agreement     America Online, Inc./BBN Corporation CONFIDENTIAL
Schedule B                   Schedule B - Page 29
<PAGE>

                       CONFIDENTIAL TREATMENT REQUESTED

               (iii) the decommissioning of Dedicated Dial-Up Access Ports
                     pursuant to this Subsection (a) shall not materially change
                     Customer's proportional distribution of Dedicated Dial-Up
                     Access Ports across Existing Calling Areas; and

               (iv)  if the decommissioning of Dedicated Dial-Up Access Ports
                     pursuant to this Subsection (a) causes the aggregate number
                     of Dial-Up Access Ports to fall below [*Material Omitted
                     and Separately Filed Under an Application for Confidential
                     Treatment] of the number of Dedicated Dial-Up Access Ports
                     comprising the Dial-Up Purchase Commitment, then Vendor
                     may, upon six months' prior notice to Customer, [*Material
                     Omitted and Separately Filed Under an Application for
                     Confidential Treatment], Vendor shall provide Transition
                     Assistance pursuant to Section 13.4 of the Master
                     Agreement.

          (b)  Customer may decommission any Dedicated Dial-Up Access Ports
               other than those to which Subsection (a) of this Section applies
               (including (A) any Dedicated Dial-Up Access Ports ordered at any
               time for delivery after [*Material Omitted and Separately Filed
               Under an Application for Confidential Treatment], and (B) any
               Dedicated Dial-Up Access Ports ordered in excess of those
               necessary to satisfy the Dial-Up Purchase Commitment), without
               liability and as of a decommissioning date specified by Customer
               upon one hundred twenty (120) days' prior written notice to
               Vendor; provided, however, that Customer may decommission
               Dedicated Dial-Up Access Ports pursuant this Subsection only to
               the extent that the first day of the month in which Final
               Acceptance occurred for such ports is at least twelve (12) months
               prior to the decommissioning date requested by Customer pursuant
               to this Subsection (b).

          (c)  Customer shall not be responsible for any charges for a Dedicated
               Dial-Up Access Port to the extent such charges correspond to the
               time after the requested decommissioning date of which Customer
               provides Vendor with notification pursuant to this Schedule B.

     8.3. Adjustments to Pricing for Dial-Up Access Services.
          --------------------------------------------------

          (a)  New Dial-Up Market Price.
               ------------------------

               (i)  Definitions.

                    (1)  "New Dial-Up Market Price" for any Dial-Up Access shall
                         mean the price [*Material Omitted and Separately Filed
                         Under an Application for Confidential Treatment] to
                         Customer by any Dial-Up Market Vendor for Comparable
                         Dial-Up Services. To calculate the New Dial-Up Market
                         Price pursuant to this Subsection, the price for
                         [*Material Omitted and Separately Filed Under an
                         Application for Confidential Treatment] shall be
                         reasonably adjusted to reflect the difference between
                         the [*Material Omitted and Separately

--------------------------------------------------------------------------------
Network Services Agreement     America Online, Inc./BBN Corporation CONFIDENTIAL
Schedule B                   Schedule B - Page 30
<PAGE>

                       CONFIDENTIAL TREATMENT REQUESTED

                         Filed Under an Application for Confidential Treatment]
                         and the provision of [*Material Omitted and Separately
                         Filed Under an Application for Confidential Treatment]
                         by a [*Material Omitted and Separately Filed Under an
                         Application for Confidential Treatment] that (A) do not
                         include [*Material Omitted and Separately Filed Under
                         an Application for Confidential Treatment], (B) do not
                         include [*Material Omitted and Separately Filed Under
                         an Application for Confidential Treatment] to such
                         vendor for [*Material Omitted and Separately Filed
                         Under an Application for Confidential Treatment], or
                         (C) do not include [*Material Omitted and Separately
                         Filed Under an Application for Confidential Treatment]
                         to such vendor for [*Material Omitted and Separately
                         Filed Under an Application for Confidential Treatment].

                    (2)  "Dial-Up Market Vendor" shall mean a vendor (not
                         including a Special Affiliate) that at any time
                         [*Material Omitted and Separately Filed Under an
                         Application for Confidential Treatment] at least
                         [*Material Omitted and Separately Filed Under an
                         Application for Confidential Treatment]. For the
                         purpose of this Subsection, Special Affiliate shall
                         only be deemed to include Subsections (i) and (ii) of
                         the definition of "Special Affiliate" in Schedule A.

               (ii) Notification Process.

                    Customer may provide Vendor with notice at any time of a New
                    Dial-Up Market Price (each such notice, a "New Dial-Up
                    Market Price Notice" and the date of such notice as
                    determined pursuant to Section 16.4 of the Master Agreement,
                    the "New Dial-Up Market Price Notice Date"). Each New
                    Dial-Up Market Price Notice will contain (A) the New Dial-Up
                    Market Price calculation and [*Material Omitted and
                    Separately Filed Under an Application for Confidential
                    Treatment] of the[*Material Omitted and Separately Filed
                    Under an Application for Confidential Treatment] to which
                    such New Dial-Up Market Price relates and (B) information
                    sufficient to enable Vendor to match the average [*Material
                    Omitted and Separately Filed Under an Application for
                    Confidential Treatment] per [*Material Omitted and
                    Separately Filed Under an Application for Confidential
                    Treatment] at [*Material Omitted and Separately Filed Under
                    an Application for Confidential Treatment] corresponding to
                    the New Dial-Up Market Price if requested by Customer. No
                    later than thirty (30) calendar days after the New Dial-Up
                    Market Price Notice Date corresponding to a New Dial-Up
                    Market Price Notice, Vendor will respond to Customer by
                    notifying Customer in writing whether it will:

--------------------------------------------------------------------------------
Network Services Agreement     America Online, Inc./BBN Corporation CONFIDENTIAL
Schedule B                   Schedule B - Page 31
<PAGE>

                       CONFIDENTIAL TREATMENT REQUESTED

                    (1)  accept the validity of the proposed New Dial-Up Market
                         Price and reduce prices to the applicable New Dial-Up
                         Market Price in accordance with Subsection (iii) of
                         this Subsection (a),

                    (2)  accept the validity of the proposed New Dial-Up Market
                         Price and decline to reduce prices to the New Dial-Up
                         Market Price in accordance with the corresponding New
                         Dial-Up Market Price Notice, or

                    (3)  dispute the validity of the proposed New Dial-Up Market
                         Price.

                    (each a "New Dial-Up Market Price Response"). Vendor shall
                    not unreasonably dispute the validity of a proposed New
                    Dial-Up Market Price.

              (iii) Reduction Process.

                    In the event Vendor accepts a proposed New Dial-Up Market
                    Price pursuant to clause (1) of Subsection (ii) of this
                    Subsection (a), then:

                    (1)  Effective as of the Incremental New Ports MP Change
                         Date, the Monthly DAP Charge for all [*Material Omitted
                         and Separately Filed Under an Application for
                         Confidential Treatment] delivered on or after
                         [*Material Omitted and Separately Filed Under an
                         Application for Confidential Treatment] Date will be
                         reduced to the New Dial-Up Market Price set forth in
                         the corresponding New Dial-Up Market Price Notice, and
                         with respect to such New Ports, Vendor will, if
                         requested by Customer, [*Material Omitted and
                         Separately Filed Under an Application for Confidential
                         Treatment] per [*Material Omitted and Separately Filed
                         Under an Application for Confidential Treatment] at
                         [*Material Omitted and Separately Filed Under an
                         Application for Confidential Treatment] provided for
                         the [*Material Omitted and Separately Filed Under an
                         Application for Confidential Treatment] Services
                         corresponding to such New Dial-Up Market Price.

                    (2)  Effective as of the All New Ports MP Change Date, the
                         Monthly DAP Charge for all [*Material Omitted and
                         Separately Filed Under an Application for Confidential
                         Treatment] (regardless of when delivered) will be
                         reduced to the New Dial-Up Market Price set forth in
                         the corresponding [*Material Omitted and Separately
                         Filed Under an Application for Confidential Treatment]
                         Notice and with respect to such New Ports, Vendor will,
                         if requested by Customer, [*Material Omitted and
                         Separately Filed Under an Application for Confidential
                         Treatment] available per [*Material Omitted and
                         Separately Filed Under an Application for Confidential

--------------------------------------------------------------------------------
Network Services Agreement   America Online, Inc. / BBN Corporation CONFIDENTIAL
Schedule B                  Schedule B - Page 32
<PAGE>

                       CONFIDENTIAL TREATMENT REQUESTED

                         Treatment] for the [*Material Omitted and Separately
                         Filed Under an Application for Confidential Treatment]
                         Services corresponding to such [*Material Omitted and
                         Separately Filed Under an Application for Confidential
                         Treatment].

                    (3)  Effective as of the Base Port MP Change Date, the
                         Monthly EDAP Charge for all [*Material Omitted and
                         Separately Filed Under an Application for Confidential
                         Treatment] and the Monthly [*Material Omitted and
                         Separately Filed Under an Application for Confidential
                         Treatment] regardless of when delivered will be reduced
                         to the New Dial-Up Market Price set forth in the
                         corresponding New Dial-Up Market Price Notice, and with
                         respect to such New Ports and Existing Dial-Up Access
                         Ports, Vendor will, if requested by Customer, match the
                         [*Material Omitted and Separately Filed Under an
                         Application for Confidential Treatment] available per
                         [*Material Omitted and Separately Filed Under an
                         Application for Confidential Treatment] for the
                         [*Material Omitted and Separately Filed Under an
                         Application for Confidential Treatment] Services
                         corresponding to such New Dial-Up Market Price.

                    Notwithstanding the foregoing:

                    (4)  If Vendor accepts the validity of a proposed New
                         Dial-Up Market Price and reduces prices to the
                         applicable New Dial-Up Access Market Price in a given
                         calendar year, then Vendor shall not be obligated to
                         provide Customer with any additional New Dial-Up Market
                         Price Response with respect to any New Dial-Up Market
                         Price Notice for which the corresponding New Dial-Up
                         Market Price Effective Date occurs in such calendar
                         year.

                    (5)  Vendor shall not be obligated to reduce the Monthly DAP
                         Charge or the Monthly EDAP Charge, as the case may be,
                         at a rate that is[*Material Omitted and Separately
                         Filed Under an Application for Confidential Treatment]
                         than the rate at which [*Material Omitted and
                         Separately Filed Under an Application for Confidential
                         Treatment] provides [*Material Omitted and Separately
                         Filed Under an Application for Confidential Treatment]
                         relative to the applicable[*Material Omitted and
                         Separately Filed Under an Application for Confidential
                         Treatment] as measured monthly. For example, if the
                         [*Material Omitted and Separately Filed Under an
                         Application for Confidential Treatment] has committed
                         to provide [*Material Omitted and Separately Filed
                         Under an Application for Confidential Treatment] or
                         more [*Material Omitted and Separately Filed Under an
                         Application for Confidential Treatment] at the
                         [*Material Omitted and Separately Filed Under an
                         Application for Confidential Treatment] but immediately
                         following the [*Material Omitted and Separately Filed
                         Under an Application for Confidential Treatment] the
                         [*Material Omitted and Separately Filed Under an
                         Application for Confidential Treatment] or the
                         [*Material Omitted and Separately Filed Under an
                         Application for Confidential Treatment] as applicable,
                         the [*Material Omitted and Separately Filed Under an
                         Application for Confidential Treatment] has only
                         provided [*Material Omitted and Separately Filed Under
                         an Application for Confidential Treatment] at the
                         [*Material Omitted and

--------------------------------------------------------------------------------
Network Services Agreement   America Online, Inc. / BBN Corporation CONFIDENTIAL
Schedule B                  Schedule B - Page 33
<PAGE>

                       CONFIDENTIAL TREATMENT REQUESTED

                         Separately Filed Under an Application for Confidential
                         Treatment], then Vendor will only be obligated to
                         reduce the Monthly DAP Charge or Monthly EDAP Charge,
                         as the case may be, for [*Material Omitted and
                         Separately Filed Under an Application for Confidential
                         Treatment] of the [*Material Omitted and Separately
                         Filed Under an Application for Confidential Treatment]
                         as of the applicable month that are subject
                         to[*Material Omitted and Separately Filed Under an
                         Application for Confidential Treatment] at that time
                         [*Material Omitted and Separately Filed Under an
                         Application for Confidential Treatment] delivered on or
                         after the [*Material Omitted and Separately Filed Under
                         an Application for Confidential Treatment] as of such
                         date, of all[*Material Omitted and Separately Filed
                         Under an Application for Confidential Treatment] and of
                         all [*Material Omitted and Separately Filed Under an
                         Application for Confidential Treatment]. If during the
                         following month [*Material Omitted and Separately Filed
                         Under an Application for Confidential Treatment] has
                         provided an additional [*Material Omitted and
                         Separately Filed Under an Application for Confidential
                         Treatment] at the [*Material Omitted and Separately
                         Filed Under an Application for Confidential Treatment],
                         then Vendor will be obligated to reduce the Monthly DAP
                         Charge or Monthly EDAP Charge, as the case may be,
                         [*Material Omitted and Separately Filed Under an
                         Application for Confidential Treatment] as of the
                         applicable month that are subject to a [*Material
                         Omitted and Separately Filed Under an Application for
                         Confidential Treatment] at that time (i.e., for
                         [*Material Omitted and Separately Filed Under an
                         Application for Confidential Treatment] delivered on or
                         after the [*Material Omitted and Separately Filed Under
                         an Application for Confidential Treatment] as of such
                         date, of all[*Material Omitted and Separately Filed
                         Under an Application for Confidential Treatment] as of
                         the [*Material Omitted and Separately Filed Under an
                         Application for Confidential Treatment] as of the
                         [*Material Omitted and

--------------------------------------------------------------------------------
Network Services Agreement   America Online, Inc. / BBN Corporation CONFIDENTIAL
Schedule B                  Schedule B - Page 34
<PAGE>

                       CONFIDENTIAL TREATMENT REQUESTED

                         Separately Filed Under an Application for Confidential
                         Treatment].

                    (6)  Vendor shall not be obligated to [*Material Omitted and
                         Separately Filed Under an Application for Confidential
                         Treatment] per[*Material Omitted and Separately Filed
                         Under an Application for Confidential Treatment]
                         at[*Material Omitted and Separately Filed Under an
                         Application for Confidential Treatment] for
                         the[*Material Omitted and Separately Filed Under an
                         Application for Confidential Treatment] corresponding
                         to a New Dial-Up Market Price at a rate that is
                         [*Material Omitted and Separately Filed Under an
                         Application for Confidential Treatment] than the rate
                         in which the [*Material Omitted and Separately Filed
                         Under an Application for Confidential Treatment]
                         provides [*Material Omitted and Separately Filed Under
                         an Application for Confidential Treatment]
                         per[*Material Omitted and Separately Filed Under an
                         Application for Confidential Treatment] at [*Material
                         Omitted and Separately Filed Under an Application for
                         Confidential Treatment] for Comparable Dial-Up Services
                         relative to the applicable Dial-Up Market Vendor
                         Trigger, as measured monthly.

                    (7)  [*Material Omitted and Separately Filed Under an
                         Application for Confidential Treatment] shall be
                         applicable only during such periods as [*Material
                         Omitted and Separately Filed Under an Application for
                         Confidential Treatment] at such [*Material Omitted and
                         Separately Filed Under an Application for Confidential
                         Treatment], or a[*Material Omitted and Separately Filed
                         Under an Application for Confidential Treatment] from
                         a[*Material Omitted and Separately Filed Under an
                         Application for Confidential Treatment].

               (iv) Decommissioning Process.

                    If Vendor declines to reduce the Monthly DAP Charge or the
                    Monthly EDAP Charge to the New Dial-Up Market Price pursuant
                    to clause (2) of Subsection (ii) of this Subsection (a),
                    then Customer may, in its sole discretion, do either or both
                    of the following: (A) terminate the Dial-Up Purchase
                    Commitment, and (B) decommission Dedicated Dial-Up Access
                    Ports, subject to the following restrictions:

                    (1)  Customer will provide [*Material Omitted and Separately
                         Filed Under an Application for Confidential Treatment]
                         days prior written notice of the calling areas in which
                         Dedicated Dial-Up Access Ports are to be
                         decommissioned, as well as the

--------------------------------------------------------------------------------
Network Services Agreement   America Online, Inc. / BBN Corporation CONFIDENTIAL
Schedule B                  Schedule B - Page 35
<PAGE>

                       CONFIDENTIAL TREATMENT REQUESTED

                         associated quantities of Dedicated Dial-Up Access Ports
                         to be decommissioned in each such area;

                    (2)  Customer may only decommission a number of Dedicated
                         Dial-Up Access Ports no greater than the number of
                         Dedicated Dial-Up Access Ports that are provided to
                         [*Material Omitted and Separately Filed Under an
                         Application for Confidential Treatment] by other
                         [*Material Omitted and Separately Filed Under an
                         Application for Confidential Treatment] at or below
                         such[*Material Omitted and Separately Filed Under an
                         Application for Confidential Treatment].

                    (3)  The effective date of decommission applicable to a
                         Existing Dial-Up Access Port shall not be earlier than
                         [*Material Omitted and Separately Filed Under an
                         Application for Confidential Treatment].

                    (4)  The decommissioning of Dedicated Dial-Up Access Ports
                         pursuant to this Subsection (iv) shall result in the
                         same approximate weighted distribution of Dedicated
                         Dial-Up Access Ports across Existing Calling Areas.

                    (5)  The right to decommission arising from any particular
                         New Dial-Up Market Price Notice shall cease, on a
                         prospective basis if and when Vendor delivers a New
                         Dial-Up Market Price Response, in response to a later
                         New Dial-Up Market Price Notice, accepting a proposed
                         New Dial-Up Market Price pursuant to clause (1) of
                         Subsection (ii) of this Subsection (a) .

               (v)  Dispute Resolution Process.

                    If Vendor reasonably disputes the validity of the New
                    Dial-Up Market Price pursuant to clause (3) of Subsection
                    (ii) of this Subsection (a), then each Party shall promptly
                    escalate to the senior-executive level all efforts by such
                    Party to resolve such dispute.

               (vi) Example.

                    For example:

                    (1)  If Customer provides Vendor with a New Dial-Up Market
                         Price Notice for which the New Dial-Up Market Price
                         Notice Date is [*Material Omitted and Separately Filed
                         Under an Application for Confidential Treatment], and
                         Vendor accepts the proposed New Dial-Up Market Price
                         pursuant to clause (A) of Subsection (ii) of this
                         Subsection (a), then (x) the New Dial-Up Market Price
                         Effective Date would be [*Material Omitted and
                         Separately Filed Under an Application for Confidential
                         Treatment], and (y) pursuant to Schedule A, the
                         Incremental

--------------------------------------------------------------------------------
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Schedule B                  Schedule B - Page 36
<PAGE>

                       CONFIDENTIAL TREATMENT REQUESTED

                         New Ports MP Change Date would be [*Material Omitted
                         and Separately Filed Under an Application for
                         Confidential Treatment], the All New Ports MP Change
                         Date would be [*Material Omitted and Separately Filed
                         Under an Application for Confidential Treatment], and
                         the Base Port MP Change Date would be [*Material
                         Omitted and Separately Filed Under an Application for
                         Confidential Treatment].

                    (2)  Pursuant to Subsection (iii)(1) of this Subsection (a),
                         and except as otherwise required pursuant to the
                         restrictions described in Subsections (iii)(5),
                         (iii)(6), and (iii)(7) of this Subsection (a), as of
                         [*Material Omitted and Separately Filed Under an
                         Application for Confidential Treatment], the Monthly
                         DAP Charge for all[*Material Omitted and Separately
                         Filed Under an Application for Confidential Treatment]
                         delivered on or after [*Material Omitted and Separately
                         Filed Under an Application for Confidential Treatment]
                         would be reduced to the New Dial-Up Market Price set
                         forth in the corresponding New Dial-Up Market Price
                         Notice, and with respect to such [*Material Omitted and
                         Separately Filed Under an Application for Confidential
                         Treatment], Vendor would, if requested by Customer,
                         [*Material Omitted and Separately Filed Under an
                         Application for Confidential Treatment] per[*Material
                         Omitted and Separately Filed Under an Application for
                         Confidential Treatment] at peak provided for the
                         [*Material Omitted and Separately Filed Under an
                         Application for Confidential Treatment] corresponding
                         to such New Dial-Up Market Price. Pursuant to
                         Subsection (iii)(4) of this Subsection (a), Vendor
                         would not be obligated to provide Customer with any
                         additional New Dial-Up Market Price Response with
                         respect to any New Dial-Up Market Price Notice for
                         which the corresponding New Dial-Up Market Price
                         Effective Date occurs in [*Material Omitted and
                         Separately Filed Under an Application for Confidential
                         Treatment].

                    (3)  Pursuant to Subsection (iii)(2) of this Subsection (a),
                         as of [*Material Omitted and Separately Filed Under an
                         Application for Confidential Treatment], the Monthly
                         DAP Charge for all [*Material Omitted and Separately
                         Filed Under an Application for Confidential Treatment]
                         regardless of when delivered would be reduced to the
                         New Dial-Up Market Price set forth in the corresponding
                         New Dial-Up Market Price Notice, and with respect to
                         such [*Material Omitted and Separately Filed Under an
                         Application for Confidential Treatment], Vendor would,
                         if requested by Customer, [*Material Omitted and
                         Separately Filed Under an Application for Confidential
                         Treatment] per [*Material

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                       CONFIDENTIAL TREATMENT REQUESTED

                         Omitted and Separately Filed Under an Application for
                         Confidential Treatment] at [*Material Omitted and
                         Separately Filed Under an Application for Confidential
                         Treatment] for the [*Material Omitted and Separately
                         Filed Under an Application for Confidential Treatment]
                         corresponding to such New Dial-Up Market Price. Such
                         reduction would not be inconsistent with Subsection
                         (iii)(4) of this Subsection (a), because such reduction
                         was made pursuant to the same New Dial-Up Market Price
                         Notice that reduced the Monthly DAP Charge pursuant to
                         Subsection (2) of this Subsection (vi).

                    (4)  Pursuant to Subsection (iii)(3) of this Subsection (a),
                         as of [*Material Omitted and Separately Filed Under an
                         Application for Confidential Treatment] and the
                         [*Material Omitted and Separately Filed Under an
                         Application for Confidential Treatment] for all
                         [*Material Omitted and Separately Filed Under an
                         Application for Confidential Treatment] regardless of
                         when delivered will be reduced to the New Dial-Up
                         Market Price set forth in the corresponding New Dial-Up
                         Market Price Notice, and with respect to such all
                         [*Material Omitted and Separately Filed Under an
                         Application for Confidential Treatment], Vendor will,
                         if requested by Customer, [*Material Omitted and
                         Separately Filed Under an Application for Confidential
                         Treatment] per [*Material Omitted and Separately Filed
                         Under an Application for Confidential Treatment] at
                         [*Material Omitted and Separately Filed Under an
                         Application for Confidential Treatment] corresponding
                         to such New Dial-Up Market Price.

                    (5)  If Customer provides Vendor with another New Dial-Up
                         Market Price Notice for which the New Dial-Up Market
                         Price Notice Date is [*Material Omitted and Separately
                         Filed Under an Application for Confidential Treatment],
                         Vendor would be obligated to provide Customer with a
                         New Dial-Up Market Price Response pursuant to
                         Subsection (ii) of this Subsection. Such obligation
                         would not be contrary to Subsection (iii)(4) of this
                         Subsection (a), because the New Dial-Up Market Price
                         Effective Date for such New Dial-Up Market Price Notice
                         would be [*Material Omitted and Separately Filed Under
                         an Application for Confidential Treatment]. If Vendor
                         accepts such proposed New Dial-Up Market Price pursuant
                         to clause (1) of Subsection (ii) of this Subsection
                         (a), then effective [*Material Omitted and Separately
                         Filed Under an Application for Confidential Treatment],
                         the Monthly DAP Charge for [*Material Omitted and
                         Separately Filed Under an Application for Confidential
                         Treatment] regardless of

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                       CONFIDENTIAL TREATMENT REQUESTED

                         when delivered would be reduced to such New Dial-Up
                         Market Price, and with respect to such [*Material
                         Omitted and Separately Filed Under an Application for
                         Confidential Treatment], Vendor would, if requested by
                         Customer, [*Material Omitted and Separately Filed Under
                         an Application for Confidential Treatment] per
                         [*Material Omitted and Separately Filed Under an
                         Application for Confidential Treatment] at [*Material
                         Omitted and Separately Filed Under an Application for
                         Confidential Treatment] for the [*Material Omitted and
                         Separately Filed Under an Application for Confidential
                         Treatment] corresponding to such New Dial-Up Market
                         Price. Further, pursuant to Subsection (iii)(3) of this
                         Subsection (a), as of [*Material Omitted and Separately
                         Filed Under an Application for Confidential Treatment],
                         the Monthly EDAP Charge will be reduced to such New
                         Dial-Up Market Price, and with respect to [*Material
                         Omitted and Separately Filed Under an Application for
                         Confidential Treatment], Vendor will, if requested by
                         Customer, [*Material Omitted and Separately Filed Under
                         an Application for Confidential Treatment] per
                         [*Material Omitted and Separately Filed Under an
                         Application for Confidential Treatment] at [*Material
                         Omitted and Separately Filed Under an Application for
                         Confidential Treatment] or the [*Material Omitted and
                         Separately Filed Under an Application for Confidential
                         Treatment] corresponding to such New Dial-Up Market
                         Price.

          (b)  Most-Favored Customer.
               ---------------------

               (i)  As long as the aggregate number of Dial-Up Access Ports then
                    being purchased or ordered by Customer exceeds that of any
                    other customer of Vendor, Vendor shall not provide dial-up
                    access services that are Comparable Dial-Up Services to any
                    other Applicable DUP Purchaser (1) at prices that are lower
                    than those charged or available to Customer under this
                    Agreement, and for a [*Material Omitted and Separately Filed
                    Under an Application for Confidential Treatment] , or for
                    [*Material Omitted and Separately Filed Under an Application
                    for Confidential Treatment] that are in the aggregate equal
                    to or less than the [*Material Omitted and Separately Filed
                    Under an Application for Confidential Treatment] that
                    [*Material Omitted and Separately Filed Under an Application
                    for Confidential Treatment] hereunder or (2) pursuant to
                    terms and conditions more favorable to such Applicable DUP
                    Purchaser than the terms and conditions of this Schedule B
                    and Master Agreement, in each case, without first offering
                    such lower price and other more favorable terms and
                    conditions to Customer, within thirty (30) calendar days of
                    contractually committing to such price and other terms with
                    another customer. As of the Effective Date, Vendor

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                       CONFIDENTIAL TREATMENT REQUESTED

                    acknowledges that the aggregate number of Dial-Up Access
                    Ports being purchased or ordered by Customer exceeds that of
                    any other customer of Vendor. In the event that the
                    aggregate number of Dial-Up Access Ports being purchased or
                    ordered by Customer at any time during the Term does not
                    exceed that of any other customer of Vendor, Vendor shall
                    provide Customer with written notification of such event
                    within thirty (30) calendar days of the occurrence of such
                    event. For the purposes of this Subsection, prices "charged
                    or available to Customer hereunder" for Dedicated Dial-Up
                    Access Ports shall be determined by [*Material Omitted and
                    Separately Filed Under an Application for Confidential
                    Treatment] the applicable [*Material Omitted and Separately
                    Filed Under an Application for Confidential Treatment] and
                    [*Material Omitted and Separately Filed Under an Application
                    for Confidential Treatment] in proportion to the number of
                    [*Material Omitted and Separately Filed Under an Application
                    for Confidential Treatment] and [*Material Omitted and
                    Separately Filed Under an Application for Confidential
                    Treatment] or [*Material Omitted and Separately Filed Under
                    an Application for Confidential Treatment] by [*Material
                    Omitted and Separately Filed Under an Application for
                    Confidential Treatment]. "Applicable DUP Purchaser" shall
                    mean any party (including any Vendor Affiliate that resells
                    Dial-Up Access purchased from Vendor or another Vendor
                    Affiliate) that is obligated to purchase, that actually
                    purchases, or that seeks to purchase from Vendor or its
                    Affiliates Dial-Up Access at any time equivalent to more
                    than [*Material Omitted and Separately Filed Under an
                    Application for Confidential Treatment] Dial-Up Access
                    Ports.

               (ii) As long as the aggregate number of Dial-Up Access Ports then
                    being purchased or ordered by Customer exceeds that of any
                    other customer of Vendor, to the extent that Vendor provides
                    dial-up access services that are not [*Material Omitted and
                    Separately Filed Under an Application for Confidential
                    Treatment, then Vendor shall offer, on a quarterly basis, to
                    provide to Customer such dial-up access services at the
                    prices charged or available to, and upon the terms and
                    conditions applicable to, [*Material Omitted and Separately
                    Filed Under an Application for Confidential Treatment];
                    provided, however, that if Customer's service requirements
                    would necessitate changes to such terms and conditions, the
                    Parties shall work in good faith to adjust such terms and
                    conditions as mutually agreed to satisfy such requirements.
                    To the extent that Customer accepts such offer of dial-up
                    access services that are not [*Material Omitted and
                    Separately Filed Under an Application for Confidential
                    Treatment] from Vendor, Vendor shall provide such services
                    as ordered by Customer pursuant to a separate Schedule to
                    the Master Agreement, such services shall be deemed Services
                    to which the Master Agreement applies, such services shall
                    be subject to most-favored customer terms and conditions
                    substantially similar to those set forth in this Subsection
                    (b), and Customer may [*Material Omitted and Separately
                    Filed Under an Application for

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                       CONFIDENTIAL TREATMENT REQUESTED

                    Confidential Treatment]. In the event of [*Material Omitted
                    and Separately Filed Under an Application for Confidential
                    Treatment], Customer shall have no further liability to
                    Vendor with respect to such portion of the Dial-Up Purchase
                    Commitment replaced pursuant to this Subsection (ii).

              (iii) As long as the aggregate number of Dial-Up Access Ports
                    then being purchased or ordered by Customer exceeds that of
                    any other customer of Vendor, Vendor shall offer to
                    Customer, Comparable Dial-Up Services provided or offered by
                    any Vendor Affiliate to an Applicable DUP Purchaser (1) at
                    prices that are equal to or lower than those charged or
                    available to such Applicable DUP Purchaser for such
                    services, for a commitment by such Applicable DUP Purchaser
                    to order or purchase volumes, or for actual orders or
                    purchases of volumes, that are in the aggregate equal to or
                    less than the equivalent volumes that Customer is obligated
                    to purchase under the Agreement, and (2) pursuant to terms
                    and conditions that are at least as favorable or more
                    favorable to Customer than the terms and conditions
                    applicable to or available to an Applicable DUP Purchaser.

               (iv) For any price proposal made by Vendor to Customer at any
                    time during the Term, Vendor shall in good faith represent
                    to Customer in writing whether or not such proposal is being
                    made for reasons that include Vendor's belief that an
                    adjustment may be required pursuant to this Subsection (b).

               (v)  Customer may audit Vendor's compliance with this Subsection
                    (b) pursuant to Article 10 of the Master Agreement. In the
                    event that Vendor fails to comply with this Subsection (b)
                    (e.g., fails to adjust pricing in accordance with this
                    Subsection (b)), then Vendor shall rebate to Customer, with
                    respect to each Dedicated Dial-Up Access Port purchased
                    hereunder, the difference between (1) the price actually
                    paid by Customer hereunder, and (2) the lower price provided
                    to the third party purchasing the Comparable Dial-Up
                    Services from Vendor, retroactive to the date Vendor
                    provided the lower price to such third party, together with
                    interest computed in the same manner as described in Section
                    9.2 of the Master Agreement on such rebated amounts from
                    such date.

          (c)  Regulatory Changes Affecting Pricing.
               ------------------------------------

               In the event that any change in applicable Federal regulations
               results in a significant, demonstrable change in Vendor's costs
               to provide the Dial-Up Access Services, then:

               (i)  in the case of a cost increase, Vendor may pass such
                    applicable cost increase along to Customer on an
                    Out-of-Pocket Expense basis so long as such increase is
                    passed along to all of Vendor's other Dial-Up Access

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                    customers to which such costs are not prohibited from being
                    passed; provided, however, Customer may elect, with 120 days
                    notice, to decommission in accordance with Subsection
                    (a)(iv) of this Section any of the Dial-Up Access Ports
                    affected by such Federal regulatory cost increase (however,
                    Customer shall not be required to pay such cost increase
                    during the 120-day decommissioning notice period); provided
                    further, however, that (A) the decommissioning of Dedicated
                    Dial-Up Access Ports across the Vendor Network pursuant to
                    this Subsection shall be in proportion to the approximate
                    weighted distribution of Dedicated Dial-Up Access Ports
                    across Existing Calling Areas, and (B) the date and,
                    proportional rate restrictions on decommissioning in
                    Subsection (a)(iv) of this Section shall not apply with
                    respect to decommissioning under this Section; and

               (ii) in the event of a cost decrease, Vendor shall pass such
                    decrease to Customer.

               In connection with any such increase or decrease, Vendor shall
               identify the Dial-Up Access Ports affected by such regulatory
               cost change and the amount of the applicable change to the
               Monthly EDAP Charge or Monthly DAP Charge for such affected
               Dial-Up Access Ports. Any such regulatory cost change passed
               -through to Customer shall take effect as of the first day of the
               calendar month immediately following delivery of the regulatory
               cost change notice and shall continue in effect until the date on
               which the next New Dial-Up Market Price becomes applicable to
               such affected Dial-Up Access Ports.

     8.4. Normalization Methodology And Conversion Of Services.
          ----------------------------------------------------

          (a)  Normalization Methodology.
               -------------------------

               For purposes of Sections 2.8(c) and 8.3(b)(ii) of this Schedule
               B, and for purposes of the definitions of "Other Vendors' Decom
               Share" and "Vendor's Decom Share" set forth in Schedule A, in
               order to normalize a commitment to order or purchase dial-up
               access provided on a usage basis with a commitment to order or
               purchase Dedicated Dial-Up Access Ports provided under this
               Agreement, a commitment to order or purchase [*Material Omitted
               and Separately Filed Under an Application for Confidential
               Treatment] shall be deemed equivalent to a commitment to purchase
               one (1) Dedicated Dial-Up Access Port for such month (such
               conversion methodology collectively the "Normalization
               Methodology").

          (b)  Conversion of Services.
               ----------------------

               Upon Customer's request, Vendor shall reasonably and in good
               faith discuss with Customer without further obligation the
               modification of the pricing methodologies applicable to the
               Dial-Up Access Services that may be purchased by Customer under
               this Schedule B as necessary to convert certain Dial-Up Access
               Services to hourly or similar usage based pricing.

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                       CONFIDENTIAL TREATMENT REQUESTED

     8.5. Technological Change.
          --------------------

          Vendor acknowledges that quality of the Dial-Up Access Services is
          critical to the satisfaction of the users of Customer's services and
          will work to minimize any quality issues associated with the rapid
          implementation of new service technologies.

          (a)  Changes in Dial-Up Access Platform.
               ----------------------------------

               (i)  In the event that Vendor determines that an access platform
                    different from that which is used as of the Effective Date
                    to provide Dedicated Dial-Up Access Ports to Customer
                    represents a superior value, or otherwise may make such
                    platform desirable, Vendor may utilize such different access
                    technology; provided, however, that:

               (ii) Vendor shall provide Customer with notification of such
                    different access technology upon Vendor's determination to
                    utilize such different access technology, which notice shall
                    be provided no less than sixty (60) days' before deploying
                    such change;

              (iii) such different access technology is not utilized in
                    conjunction with then-existing access technology for any
                    given telephone number for more than forty-five (45) days;
                    and

               (iv) if such different access technology does not provide (or
                    enable Vendor to provide) any reports required under Section
                    6.3(o) or 7.3(a) of this Schedule B other than the reports
                    described in Section 7.3(a)(i) of this Schedule B, then:

                    (1)  Vendor may deploy not more than [*Material Omitted and
                         Separately Filed Under an Application for Confidential
                         Treatment] such Dedicated Dial-Up Access Ports (in the
                         aggregate for all such different access technologies
                         that do not provide such reports) (each of such ports a
                         "Reportless Port");

                    (2)  with respect to any Reportless Port, Vendor shall use
                         all commercially reasonable efforts to provide such
                         reports as soon as practicable, but in no event later
                         than [*Material Omitted and Separately Filed Under an
                         Application for Confidential Treatment] after
                         acceptance of such Reportless Port; and

                    (3)  if Vendor is unable to provide such reports for a
                         Reportless Port for [*Material Omitted and Separately
                         Filed Under an Application for Confidential Treatment]
                         days of acceptance of such Reportless Port, then Vendor
                         shall immediately remove from service any such
                         Reportless Port.

               In no event shall Vendor provide any Dedicated Dial-Up Access
               Ports that do not provide the reports described in Section
               7.3(a)(i) of this Schedule B. Upon the request of Customer,
               Vendor shall identify which access platform is then

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                       CONFIDENTIAL TREATMENT REQUESTED

               being utilized for each telephone number used to provide
               Dedicated Dial-Up Access Ports.

          (b)  Technology Briefing.
               -------------------

               Vendor will provide Customer with a semi-annual technology
               briefing detailing Vendor's near- and medium- term plans for the
               introduction of new technology and new Internet-related services.
               Information exchanged by the Parties in conjunction with such
               briefing shall be deemed Confidential Information for the
               purposes of the Agreement.

9.   SPECIFICATIONS AND ACCEPTANCE CRITERIA

     9.1. Specifications.
          --------------

          Dedicated Dial-Up Access Ports provided hereunder shall fully conform
          with the following Specifications (collectively, the "Dial-Up Access
          Specifications"):

          (a)  By [*Material Omitted and Separately Filed Under an Application
               for Confidential Treatment], Vendor will provision end-to-end
               bandwidth such that average bandwidth available per user at peak
               will be [*Material Omitted and Separately Filed Under an
               Application for Confidential Treatment].

          (b)  The Dial-Up Access Services shall fully support and be in
               conformance with Customer's access methods, access technology,
               hub architecture, and other access methods that may become
               available to Customer from time to time. Access methods shall
               include:

               (i)  [*Material Omitted and Separately Filed Under an Application
                    for Confidential Treatment];

               (ii) [*Material Omitted and Separately Filed Under an Application
                    for Confidential Treatment];

              (iii) [*Material Omitted and Separately Filed Under an Application
                    for Confidential Treatment];

               (iv) [*Material Omitted and Separately Filed Under an Application
                    for Confidential Treatment];

               (v)  [*Material Omitted and Separately Filed Under an Application
                    for Confidential Treatment];

               (vi) [*Material Omitted and Separately Filed Under an Application
                    for Confidential Treatment];

              (vii) [*Material Omitted and Separately Filed Under an Application
                    for Confidential Treatment];

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                       CONFIDENTIAL TREATMENT REQUESTED

             (viii) [*Material Omitted and Separately Filed Under an Application
                    for Confidential Treatment] (including those provided by
                    Customer and any other Customer-offered service) as
                    requested by Customer at [*Material Omitted and Separately
                    Filed Under an Application for Confidential Treatment],
                    provided that the cost of [*Material Omitted and Separately
                    Filed Under an Application for Confidential Treatment],
                    subject to prior agreement by Vendor and Customer on how
                    routing is implemented. Interconnect costs of service to
                    [*Material Omitted and Separately Filed Under an Application
                    for Confidential Treatment] will be treated as an [*Material
                    Omitted and Separately Filed Under an Application for
                    Confidential Treatment] until the earlier of [*Material
                    Omitted and Separately Filed Under an Application for
                    Confidential Treatment], and [*Material Omitted and
                    Separately Filed Under an Application for Confidential
                    Treatment] the date on which [*Material Omitted and
                    Separately Filed Under an Application for Confidential
                    Treatment]; provided however that any such [*Material
                    Omitted and Separately Filed Under an Application for
                    Confidential Treatment] charged to Customer by Vendor will
                    be reduced on a monthly basis by an amount equal to the
                    [*Material Omitted and Separately Filed Under an Application
                    for Confidential Treatment];

               (ix) [*Material Omitted and Separately Filed Under an Application
                    for Confidential Treatment], provided that the cost of
                    user's [*Material Omitted and Separately Filed Under an
                    Application for Confidential Treatment], subject to prior
                    agreement by Vendor and Customer on how routing is
                    implemented; and

               (x)  [*Material Omitted and Separately Filed Under an Application
                    for Confidential Treatment], provided that the cost
                    [*Material Omitted and Separately Filed Under an Application
                    for Confidential Treatment] does not exceed the cost of
                    [*Material Omitted and Separately Filed Under an Application
                    for Confidential Treatment], subject to prior agreement by
                    Vendor and Customer on how routing is implemented.

          (c)  Vendor, in its network design and topology, shall comply with
               IETF approved and adopted standards applicable to the access
               methods described in Subsection (b) of this Section.

     9.2. Acceptance Criteria.
          -------------------

          The following Acceptance Criteria shall apply to Dedicated Dial-Up
          Access Ports:

          Newly activated Dedicated Dial-Up Access Ports will fail Dial-Up
          Acceptance Testing if any of the following thresholds is met:

          (a)  greater than [*Material Omitted and Separately Filed Under an
               Application for Confidential Treatment];

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                       CONFIDENTIAL TREATMENT REQUESTED

          (b)  greater than [*Material Omitted and Separately Filed Under an
               Application for Confidential Treatment] (such data will be
               provided by Vendor for the [*Material Omitted and Separately
               Filed Under an Application for Confidential Treatment];

          (c)  greater than [*Material Omitted and Separately Filed Under an
               Application for Confidential Treatment] which successfully
               [*Material Omitted and Separately Filed Under an Application for
               Confidential Treatment] to the [*Material Omitted and Separately
               Filed Under an Application for Confidential Treatment] to connect
               [*Material Omitted and Separately Filed Under an Application for
               Confidential Treatment]

          provided, however, that notwithstanding the foregoing, [*Material
          Omitted and Separately Filed Under an Application for Confidential
          Treatment]. The Acceptance Test Period will be contingent upon
          Customer's receiving the[*Material Omitted and Separately Filed Under
          an Application for Confidential Treatment] beginning with a [*Material
          Omitted and Separately Filed Under an Application for Confidential
          Treatment]. Customer will not [*Material Omitted and Separately Filed
          Under an Application for Confidential Treatment].

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                       CONFIDENTIAL TREATMENT REQUESTED

                                   EXHIBIT B-1

                           Dial-Up Purchase Commitment

1.   CONFIDENTIALITY

     This Exhibit specifies the Monthly Targets for Customer's Dial-Up Purchase
     Commitments pursuant to Schedule B. The Parties specifically acknowledge
     that the purchase commitment information contained herein is highly
     confidential and that its disclosure to the public or third parties could
     cause significant harm to either Customer or Vendor or both.

2.   DIAL-UP PURCHASE COMMITMENT

          (a)  The Monthly Target for the following months shall be as follows:

          (b)  For [*Material Omitted and Separately Filed Under an Application
               for Confidential Treatment] Monthly Target shall be an amount
               determined [*Material Omitted and Separately Filed Under an
               Application for Confidential Treatment];

          (c)  For [*Material Omitted and Separately Filed Under an Application
               for Confidential Treatment] Target shall be an amount determined
               [*Material Omitted and Separately Filed Under an Application for
               Confidential Treatment] that is no less than [*Material Omitted
               and Separately Filed Under an Application for Confidential
               Treatment] but no more than [*Material Omitted and Separately
               Filed Under an Application for Confidential Treatment];

          (d)  For [*Material Omitted and Separately Filed Under an Application
               for Confidential Treatment] the Monthly Target shall be an amount
               determined [*Material Omitted and Separately Filed Under an
               Application for Confidential Treatment] that is no less than
               [*Material Omitted and Separately Filed Under an Application for
               Confidential Treatment] but no more than [*Material Omitted and
               Separately Filed Under an Application for Confidential
               Treatment]; and

          (e)  For [*Material Omitted and Separately Filed Under an Application
               for Confidential Treatment] the Monthly Target shall [*Material
               Omitted and Separately Filed Under an Application for
               Confidential Treatment] (except as otherwise mutually agreed upon
               by the Parties).

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                       CONFIDENTIAL TREATMENT REQUESTED

                                   EXHIBIT B-2

                       Prices for Dial-Up Access Services

1.   CONFIDENTIALITY

     This Exhibit specifies the prices for Dial-Up Access Services provided
     pursuant to the Master Agreement and Schedule B. The Parties specifically
     acknowledge that the pricing information contained herein is highly
     confidential and that its disclosure to the public or third parties could
     cause significant harm to either Customer or Vendor or both.

2.   MARKET PRICE FOR EXISTING DIAL-UP ACCESS PORTS

     The Monthly EDAP Charge shall be set at [*Material Omitted and Separately
     Filed Under an Application for Confidential Treatment], which price,
     effective from [*Material Omitted and Separately Filed Under an Application
     for Confidential Treatment] through [*Material Omitted and Separately Filed
     Under an Application for Confidential Treatment], shall be [*Material
     Omitted and Separately Filed Under an Application for Confidential
     Treatment] dollars ($[*Material Omitted and Separately Filed Under an
     Application for Confidential Treatment]). [*Material Omitted and Separately
     Filed Under an Application for Confidential Treatment] shall be further
     [*Material Omitted and Separately Filed Under an Application for
     Confidential Treatment] according to the following schedule:

          (a)  From [*Material Omitted and Separately Filed Under an Application
               for Confidential Treatment] through [*Material Omitted and
               Separately Filed Under an Application for Confidential Treatment]
               the Monthly EDAP Charge shall be [*Material Omitted and
               Separately Filed Under an Application for Confidential Treatment]
               dollars [*Material Omitted and Separately Filed Under an
               Application for Confidential Treatment];

          (b)  From [*Material Omitted and Separately Filed Under an Application
               for Confidential Treatment] through [*Material Omitted and
               Separately Filed Under an Application for Confidential Treatment]
               the Monthly EDAP Charge shall be [*Material Omitted and
               Separately Filed Under an Application for Confidential Treatment]
               dollars [*Material Omitted and Separately Filed Under an
               Application for Confidential Treatment];

          (c)  From [*Material Omitted and Separately Filed Under an Application
               for Confidential Treatment] through the remainder of [*Material
               Omitted and Separately Filed Under an Application for
               Confidential Treatment] the Monthly EDAP Charge shall be
               [*Material Omitted and Separately Filed Under an Application for
               Confidential Treatment] dollars [*Material Omitted and Separately
               Filed Under an Application for Confidential Treatment].

     Notwithstanding the foregoing, the Monthly EDAP Charge [*Material Omitted
     and Separately Filed Under an Application for Confidential Treatment] may
     be [*Material Omitted and Separately Filed Under an Application for
     Confidential Treatment (A) [*Material Omitted and Separately Filed Under an
     Application for Confidential Treatment] pursuant to Section [*Material
     Omitted and Separately Filed Under an Application for Confidential
     Treatment] to the [*Material Omitted and Separately Filed Under an
     Application for Confidential Treatment] dollars [*Material Omitted and
     Separately Filed Under an Application for Confidential Treatment] (B) the
     applicable amount [*Material Omitted and Separately Filed Under an
     Application for Confidential Treatment] (2) otherwise pursuant to Article
     [*Material Omitted and Separately Filed Under an Application for
     Confidential Treatment].

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                       CONFIDENTIAL TREATMENT REQUESTED

3.   MARKET PRICE FOR DIAL-UP ACCESS PORTS

     The Monthly DAP Charge shall be set at the [*Material Omitted and
     Separately Filed Under an Application for Confidential Treatment], which
     price, [*Material Omitted and Separately Filed Under an Application for
     Confidential Treatment] from the [*Material Omitted and Separately Filed
     Under an Application for Confidential Treatment] through [*Material Omitted
     and Separately Filed Under an Application for Confidential Treatment],
     shall be [*Material Omitted and Separately Filed Under an Application for
     Confidential Treatment]. From [*Material Omitted and Separately Filed Under
     an Application for Confidential Treatment] through [*Material Omitted and
     Separately Filed Under an Application for Confidential Treatment]
     Notwithstanding the foregoing, the Monthly DAP Charge may be [*Material
     Omitted and Separately Filed Under an Application for Confidential
     Treatment] (1) pursuant to Section [*Material Omitted and Separately Filed
     Under an Application for Confidential Treatment] to the [*Material Omitted
     and Separately Filed Under an Application for Confidential Treatment] of
     (A) the applicable amount [*Material Omitted and Separately Filed Under an
     Application for Confidential Treatment] (B) [*Material Omitted and
     Separately Filed Under an Application for Confidential Treatment] or (2)
     otherwise pursuant to Article [*Material Omitted and Separately Filed Under
     an Application for Confidential Treatment].

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Schedule B                  Schedule B-2 - Page 2
<PAGE>

                       CONFIDENTIAL TREATMENT REQUESTED

                                   SCHEDULE C

      Broadband Backhaul Services, Service Levels, Pricing and Other Terms

1.   TERM

     The term of this Schedule C shall begin on the Effective Date and shall
     expire on December 31, 2004, unless terminated earlier in accordance with
     the Agreement; provided that Customer may, with the consent of Vendor,
     renew such term for three (3) additional one (1) year periods by giving
     Vendor at least thirty (30) days notice prior to the end of the applicable
     term or renewal period (such period, as terminated earlier or so extended,
     the "Broadband Term").

2.   CONSTRUCTION OF AGREEMENT WITH RESPECT TO NON-XDSL BROADBAND SERVICES

          (a)  Although this Agreement governs Broadband Backhaul Services for
               both xDSL and other broadband services, the Parties acknowledge
               that the particular rights, duties and obligations set forth
               herein, including service levels, delivery of service, failure to
               meet service levels, failure to deliver service, the Broadband
               Specifications, and other provisions, and the impact of such
               matters on related purchase commitments as well as other rights
               and remedies, have been worked out in the particular context of
               xDSL broadband services. Therefore, although the rights, duties
               and obligations herein apply to broadband services other than
               xDSL, the Parties agree to negotiate in good faith how certain
               provisions herein that are stated in terms particularly relevant
               to xDSL broadband services will apply in the context of broadband
               services other than xDSL.

          (b)  The Parties acknowledge and agree that with respect to certain
               Broadband Backhaul Services used to provide any non-xDSL or
               non-cable broadband service with [*Material Omitted and
               Separately Filed Under an Application for Confidential Treatment
               utilized for an xDSL or cable broadband service and for which
               delivery of such non-xDSL or non-cable service is not based upon
               the [*Material Omitted and Separately Filed Under an Application
               for Confidential Treatment], the Other Broadband Purchase
               Commitment and the pricing set forth in Exhibit C-2 of this
               Schedule C shall each be adjusted, as mutually agreed, to reflect
               an appropriate methodology; provided, however, that (i) with
               respect to the adjustment to the Other Broadband Purchase
               Commitment, such adjustment shall only be made to reflect such
               appropriate methodology, and the commitment [*Material Omitted
               and Separately Filed Under an Application for Confidential
               Treatment] as such [*Material Omitted and Separately Filed Under
               an Application for Confidential Treatment] as set forth in
               [*Material Omitted and Separately Filed Under an Application for
               Confidential Treatment] and may be adjusted pursuant to the terms
               of this Schedule C shall not be increased or reduced but shall be
               applied to the adjusted methodology, and (ii) Section 7.2 of this
               Schedule C shall continue to apply to the Other Broadband
               Purchase Commitment and pricing, as adjusted.

--------------------------------------------------------------------------------
Network Services Agreement   America Online, Inc. / BBN Corporation CONFIDENTIAL
Schedule B                  Schedule C - Page 1
<PAGE>

                       CONFIDENTIAL TREATMENT REQUESTED

3.   ORDERING AND ACCEPTANCE CRITERIA

     3.1. Ordering.
          --------

          (a)  Forecasts of Customer's Expected Broadband Backhaul Services
               ------------------------------------------------------------
               Needs in New LATAs. At the start of every calendar quarter,
               ------------------
               Customer will provide Vendor with a non-binding forecast that
               sets forth those New LATAs in which Customer expects it will need
               Broadband Backhaul Services over the next three (3) calendar
               quarters.

          (b)  Ordering Broadband Backhaul Services in Existing LATAs. The
               ------------------------------------------------------
               Parties shall mutually agree upon the standards and procedures
               for ordering Broadband Backhaul Services in Existing LATAs
               (including (i) scheduling procedures, timelines, performance
               metrics and remedies, (ii) the ongoing sharing of information
               back and forth between the Parties as appropriate or necessary to
               maximize efficiencies and minimize provisioning turnarounds times
               and (iii) such other issues as the Parties may mutually agree).
               The Parties specifically agree that a principal objective of the
               ordering process shall be to meet in a timely manner Customer's
               Subscriber Line demand. The Parties shall mutually agree upon
               changes from time to time to the ordering process to facilitate
               the provision of Broadband Backhaul Services to Customer.

          (c)  Launch of Broadband Backhaul Services in New LATAs. Customer
               --------------------------------------------------
               shall direct the launch of New LATAs consistent with the timing
               of the local access provider and Customer becoming ready to
               provide xDSL service in that LATA. Any time Customer requests
               that Vendor provision Broadband Backhaul Services in a New LATA,
               Customer will provide Vendor with notice (each, a "New LATA
               Notice") specifying such LATA (as applicable), the initial
               capacity to be provided in such LATA, and the date Customer
               anticipates it will begin utilizing such Broadband Backhaul
               Services in such LATA. In the event that Customer notifies Vendor
               of a requested change in the specifics of a New LATA Notice
               provided to Vendor, the Parties will mutually agree upon the
               extent, if any, that (i) such requested change will affect the
               time period specified in Section 3.2(a) of this Schedule C, and
               (ii) Customer will pay Vendor Out-of-Pocket Expenses incurred by
               Vendor as a result of such requested change.

          (d)  Geographic Distribution. Notwithstanding the foregoing:
               -----------------------

               (i)  the distribution of Vendor Broadband Subscriber Lines
                    providing xDSL broadband services will be approximately
                    proportional to the nationwide distribution of all of the
                    Aggregate DSL Subscriber Lines; and

               (ii) the distribution of Vendor Broadband Subscriber Lines
                    providing broadband services other than xDSL will be
                    approximately proportional to the nationwide distribution of
                    all of the Aggregate Other Subscriber Lines.

               For the purposes of this Subsection (d), "distribution" means the
               distribution of the corresponding Vendor Broadband Subscriber
               Lines across rural versus urban

--------------------------------------------------------------------------------
Network Services Agreement   America Online, Inc. / BBN Corporation CONFIDENTIAL
Schedule B                  Schedule C - Page 2
<PAGE>

                       CONFIDENTIAL TREATMENT REQUESTED

               areas, across the contiguous states of the United States, and
               between Covered Subscriber Lines and non-Covered Subscriber
               Lines. In the event that Vendor believes Customer has provided
               Vendor with tasking that is inconsistent with this Subsection
               (d), the Parties will mutually agree on an equitable resolution
               consistent with the intent of this Section. In January and July
               of each calendar year, Customer shall provide Vendor with
               relevant information regarding the distribution of Aggregate
               Subscriber Lines.

          (e)  Reports on Subscriber Line Activations. At least once per week
               --------------------------------------
               Customer will provide Vendor a report on the number of Vendor
               Broadband Subscriber Lines activated from each service provider
               by LATA for the previous seven (7) day period.

     3.2. Delivery.
          --------

          (a)  General. Vendor shall provision Broadband Backhaul Services for
               -------
               each Existing LATA in accordance with the standards and
               procedures described in Section 1(b) of this Schedule C. Vendor
               shall use demonstrable good faith diligent efforts to provision
               Broadband Backhaul Services for each New LATA within [*Material
               Omitted and Separately Filed Under an Application for
               Confidential Treatment] days of its receipt of a New LATA Notice
               corresponding to such New LATA.

          (b)  Reductions in Broadband Purchase Commitments for Delivery
               ---------------------------------------------------------
               Failures.
               --------

               (i)  Definitions.

                    (1)  "Failure Percentage" means, as of a Measurement Date,
                         the percentage resulting from (i) [*Material Omitted
                         and Separately Filed Under an Application for
                         Confidential Treatment] that as of such Measurement
                         Date, Vendor has failed to [*Material Omitted and
                         Separately Filed Under an Application for Confidential
                         Treatment] pursuant to Section 1.1(a) of this Schedule
                         within the [*Material Omitted and Separately Filed
                         Under an Application for Confidential Treatment]
                         applicable to each such [*Material Omitted and
                         Separately Filed Under an Application for Confidential
                         Treatment] divided by the (ii) the sum of (A)
                         [*Material Omitted and Separately Filed Under an
                         Application for Confidential Treatment] pursuant to
                         Section 1.1(a) of this Schedule as of such [*Material
                         Omitted and Separately Filed Under an Application for
                         Confidential Treatment] plus (B) [*Material Omitted and
                         Separately Filed Under an Application for Confidential
                         Treatment] to be [*Material Omitted and Separately
                         Filed Under an Application for Confidential Treatment]
                         of this [*Material Omitted and Separately Filed Under
                         an Application for Confidential Treatment] and for
                         which the applicable [*Material Omitted

--------------------------------------------------------------------------------
Network Services Agreement     America Online, Inc./BBN Corporation CONFIDENTIAL
Schedule C                   Schedule C - Page 3
<PAGE>

                       CONFIDENTIAL TREATMENT REQUESTED

                          and Separately Filed Under an Application for
                          Confidential Treatment].

                     (2)  "Failure Threshold Percentages" means the percentage
                          set forth in the following table:
<TABLE>
                          <S>                                      <C>
                          ---------------------------------------- -------------------------------
                             [*Material Omitted and Separately      Failure Threshold Percentage
                              Filed Under an Application for
                                  Confidential Treatment]
                          ---------------------------------------- -------------------------------
                                                                       [*Material Omitted and
                                                                     Separately Filed Under an
                                                                    Application for Confidential
                                                                             Treatment]
                          ---------------------------------------- -------------------------------

                          ---------------------------------------- -------------------------------

                          ---------------------------------------- -------------------------------
</TABLE>

                     (3)  "Threshold Difference" as of a Measurement Date equals
                          the Failure Percentage minus the Failure Threshold
                          Percentage, except that the Threshold Difference can
                          never be less than zero.

               (ii)  Reduction Calculation. Reduction of the Broadband Purchase
                     Commitments shall be as set forth in Section 3.1 of Exhibit
                     C-1 of this Schedule C.

               (iii) Examples. Examples of reductions in the Broadband Purchase
                     Commitments for delivery failures are set forth in Section
                     3.2 of Exhibit C-1 of this Schedule C.

          (c)  If Vendor fails to (i) provision Broadband Backhaul Services for
               a New LATA within [*Material Omitted and Separately Filed Under
               an Application for Confidential Treatment] days of its receipt of
               a New LATA Notice corresponding to such New LATA, and (ii) use
               demonstrable good faith diligent efforts to provision Broadband
               Backhaul Services for such New LATA, then Customer may terminate
               its obligations with respect to the Broadband Backhaul Purchase
               Commitments. Upon Customer's request, Vendor shall provide
               Customer with information and supporting documentation which
               demonstrates Vendor's good faith diligent efforts to provision
               such services for the applicable New LATA within [*Material
               Omitted and Separately Filed Under an Application for
               Confidential Treatment] days of receipt of the corresponding New
               LATA Notice (e.g., documents showing Vendor's ordering of
               circuits in such New LATA).

     3.3. Acceptance Criteria.
          -------------------

          (a)  Prior to notifying Customer that Broadband Backhaul Services are
               available in any geographic area, Vendor will conduct testing
               utilizing a series of [*Material

--------------------------------------------------------------------------------
Network Services Agreement     America Online, Inc./BBN Corporation CONFIDENTIAL
Schedule C                   Schedule C - Page 4
<PAGE>

                       CONFIDENTIAL TREATMENT REQUESTED

               Omitted and Separately Filed Under an Application for
               Confidential Treatment] tests which validate [*Material Omitted
               and Separately Filed Under an Application for Confidential
               Treatment] connectivity from the service provider's [*Material
               Omitted and Separately Filed Under an Application for
               Confidential Treatment] and (ii) a series of [*Material Omitted
               and Separately Filed Under an Application for Confidential
               Treatment] that validate connectivity from the [*Material Omitted
               and Separately Filed Under an Application for Confidential
               Treatment]. Once connectivity described in Subsections (i) and
               (ii) of this Subsection (a) [*Material Omitted and Separately
               Filed Under an Application for Confidential Treatment], Vendor
               will provide Customer with notice that the Broadband Backhaul
               Services are ready for use by Customer.

          (b)  The Broadband Backhaul Services will be deemed accepted for a
               specific LATA or other relevant geographic area when the
               [*Material Omitted and Separately Filed Under an Application for
               Confidential Treatment] in accordance with the [*Material Omitted
               and Separately Filed Under an Application for Confidential
               Treatment]. Vendor will reasonably cooperate with acceptance
               testing by Customer. Customer will begin providing the Broadband
               Backhaul Services to its end-customers as soon as reasonably
               practicable after Customer completes its acceptance testing.

     3.4. Broadband Backhaul Purchase Commitments.
          ---------------------------------------

          Customer agrees to purchase Broadband Backhaul Services according to
          the purchase commitments set forth in Exhibit C-1 of this Schedule C.

4.   TERMINATION

     4.1. Vendor Termination.
          ------------------

          (a)  In the event that the aggregate number of Vendor Broadband
               Subscriber Lines:

          (b)  is less than [*Material Omitted and Separately Filed Under an
               Application for Confidential Treatment] as of [*Material Omitted
               and Separately Filed Under an Application for Confidential
               Treatment];

          (c)  is less than [*Material Omitted and Separately Filed Under an
               Application for Confidential Treatment] as of [*Material Omitted
               and Separately Filed Under an Application for Confidential
               Treatment];

          (d)  is less than [*Material Omitted and Separately Filed Under an
               Application for Confidential Treatment] as of [*Material Omitted
               and Separately Filed Under an Application for Confidential
               Treatment]; or

          (e)  is less than [*Material Omitted and Separately Filed Under an
               Application for Confidential Treatment] as of [*Material Omitted
               and Separately Filed Under an Application for Confidential
               Treatment],

--------------------------------------------------------------------------------
Network Services Agreement     America Online, Inc./BBN Corporation CONFIDENTIAL
Schedule C                   Schedule C - Page 5
<PAGE>

                       CONFIDENTIAL TREATMENT REQUESTED

               Vendor may within thirty (30) calendar days of the applicable
               calendar day set forth above for the corresponding Vendor
               Broadband Subscriber Line threshold provide Customer with notice
               of termination of this Schedule C. Such termination shall become
               effective on the date specified in such notice (which date shall
               be no earlier than one hundred fifty (150) calendar days
               following the date of such notice and no later than the end of
               the Broadband Term) unless within thirty (30) calendar days of
               the date of such notice, the number of Vendor Broadband
               Subscriber Lines is equal to or greater than such corresponding
               threshold . In the event of such termination, (i) Customer shall
               have no liability to Vendor for failure to achieve the Broadband
               Purchase Commitments, and (ii) except with respect to the
               provision of Transition Assistance pursuant to this Section,
               Vendor shall have no liability to Customer. Upon such
               termination, Vendor shall provide Transition Assistance in
               accordance with Section 13.4 of the Master Agreement. Nothing in
               this Section shall be deemed to affect the obligations of
               Customer with respect to the Broadband Purchase Commitments so
               long as Vendor has not provided Customer with a notice of
               termination pursuant to this Section.

     4.2. Termination of xDSL Field Trials.
          --------------------------------

          The xDSL field trials described in the Original Agreement for (a)
          Phoenix, Arizona, (b) San Francisco, California, (c) Birmingham,
          Alabama, (d) northern Virginia, and (e) Redmond, Washington shall be
          terminated as of January 31, 2000; provided, however, that any of such
          field trials will be continued upon the request of Customer. In the
          event of any such continuation, Customer shall reimburse Vendor for
          Out-of-Pocket Expenses incurred by Vendor as a result of such
          continuation.

5.   DESCRIPTION OF SERVICES

     Vendor shall provide nationwide (i.e., within the forty-eight contiguous
     states of the United States plus Hawaii) broadband (including xDSL, cable,
     wireless and satellite technologies) backbone integration services
     combining inter- and intra-LATA interconnects, aggregation equipment,
     co-location, backbone transport and network management control. Such
     services shall include the provision of the services described in this
     Article 5.

     5.1. Summary and Implementation Plan.
          -------------------------------

          Vendor will provide program management, network engineering,
          deployment, and operations support for broadband network services
          integration for Customer.

          (a)  Program Management.
               ------------------

               Vendor will assign a Program Management Team that will be
               responsible for the management of the provision of Broadband
               Backhaul Services as a whole. The Program Management Team will
               serve as Vendor's primary point of contact for Customer. Such
               team will coordinate the activity of all functional groups within
               Vendor and will be responsible for project and financial
               management of the Broadband Backhaul Services.

          (b)  Network Engineering.
               -------------------

--------------------------------------------------------------------------------
Network Services Agreement     America Online, Inc./BBN Corporation CONFIDENTIAL
Schedule C                   Schedule C - Page 6
<PAGE>

                       CONFIDENTIAL TREATMENT REQUESTED

               Vendor will provide network engineering expertise to address
               technical issues that arise during the deployment of the
               Broadband Backhaul Services and operation of the Vendor Network.
               Vendor will be responsible for performing network design;
               planning network expansion; documenting technical procedures;
               resolving problems escalated by the NOC; addressing architecture,
               implementation and performance issues; providing cost reduction
               recommendations; and performing continuous process improvement.

          (c)  Deployment.
               ----------

               Vendor will assign a Deployment Team that will consist of field
               engineers and technicians. Such team will be responsible for
               planning and implementing logistics, procuring equipment and
               circuits, coordinating with network service providers' access
               points, staging, integration, testing, shipping, and installing
               equipment.

          (d)  Operations.
               ----------

               Vendor's NOCs will handle the operation and maintenance of the
               Vendor Network. The NOC shall be connected to Customer's central
               facilities using a direct leased line to Customer's operations
               center.

     5.2. Design and Topology of the Vendor Network.
          ------------------------------------------

          Vendor will utilize its Global Network Infrastructure (GNI) backbone
          for transport of broadband traffic to Customer data centers; provided
          that in order to provide last mile diversity, at Customer's request,
          for up to [*Material Omitted and Separately Filed Under an Application
          for Confidential Treatment] percent of the GNI last mile capacity to
          Customer's facilities, Customer and Vendor agree to exchange local
          facilities, at no cost to either Party, for equivalent bandwidth
          exchanged. The Parties agree to establish a mutually acceptable
          bandwidth-exchanging and circuit-management process, including with
          respect to co-location space, facility access, and helping hands where
          both Parties have local facilities in each geography.

          (a)  Equipment Configuration.
               ------------------------

               Vendor acknowledges that quality of the Broadband Backhaul
               Services is critical to the satisfaction of the users of
               Customer's services and will work to minimize any quality issues
               associated with the rapid implementation of new service
               technologies (other than to the extent that such quality issues
               are caused by new service technologies directed by Customer).
               Vendor will utilize a complement of equipment at broadband POPs.
               Customer will reasonably cooperate with Vendor in the testing and
               implementation of any alternative equipment at the broadband POPs
               that Vendor desires to implement. A sample configuration of
               equipment is described below.

               [*Material Omitted and Separately Filed Under an Application for
               Confidential Treatment]. Ancillary equipment will be provided in
               each POP to

--------------------------------------------------------------------------------
Network Services Agreement     America Online, Inc./BBN Corporation CONFIDENTIAL
Schedule C                   Schedule C - Page 7
<PAGE>

                       CONFIDENTIAL TREATMENT REQUESTED

               support configuration and management functions. [*Material
               Omitted and Separately Filed Under an Application for
               Confidential Treatment].

          (b)  Points of Presence (POPs).
               --------------------------

               Vendor currently locates broadband POPs in GTE Internetworking
               GNI facilities. Such GNI facilities provide space for 19" racks,
               associated power, cabling and environmental conditioning.

          (c)  Network Topology.
               -----------------

               (i)   The Vendor Network utilized to provide Broadband Backhaul
                     Services is currently structured as a [*Material Omitted
                     and Separately Filed Under an Application for Confidential
                     Treatment]. Broadband POPs will be located at [*Material
                     Omitted and Separately Filed Under an Application for
                     Confidential Treatment].

               (ii)  Traffic from [*Material Omitted and Separately Filed Under
                     an Application for Confidential Treatment].

               (iii) Vendor's NOCs will maintain [*Material Omitted and
                     Separately Filed Under an Application for Confidential
                     Treatment].

               (iv)  [*Material Omitted and Separately Filed Under an
                     Application for Confidential Treatment] Under this Schedule
                     C, Vendor is not currently responsible for [*Material
                     Omitted and Separately Filed Under an Application for
                     Confidential Treatment].

          (d)  Vendor agrees that any changes to the Broadband Backhaul Services
               or to the Vendor Network used to provide the Broadband Backhaul
               Services will be fully functional with services provided by
               Customer without modification of, or addition to, client or host
               software used to provide services provided by Customer that
               utilize the Broadband Backhaul Services.

          (e)  In the event that Customer requests a change to the hub
               architecture, or network bandwidth from that which is described
               in this Schedule C (other than a request for increased throughput
               priced pursuant to Section 8(a) of this Schedule C), Vendor will
               provide Customer with Vendor's proposed increase, if any, to the
               prices set forth in this Schedule C. To the extent that Customer
               accepts such proposal, Vendor shall provide the Broadband
               Backhaul Services in accordance with the requested change and
               Vendor's proposal to the extent accepted by Customer.

     5.3. Deployment.
          ----------

          (a)  Vendor will take the following steps in preparation for deploying
               equipment used to provide the Broadband Backhaul Services as may
               be appropriate:

               (i)  Coordinating provisioning schedules with Customer
                    representatives;

--------------------------------------------------------------------------------
Network Services Agreement     America Online, Inc./BBN Corporation CONFIDENTIAL
Schedule C                   Schedule C - Page 8
<PAGE>

                       CONFIDENTIAL TREATMENT REQUESTED

               (ii)  Negotiating with telecommunications vendors for procurement
                     and installation of appropriate access and network
                     connections;

               (iii) Negotiating with telecommunications vendors for
                     reservations of floor space for installation of such
                     equipment;

               (iv)  Coordinating with site organizations for housing such
                     equipment and spares, and for developing agreements to
                     assist with troubleshooting activities as directed by the
                     NOC;

               (v)   Procuring equipment;

               (vi)  Receiving, storing, and tracking equipment; and

               (vii) Scheduling installations.

          (b)  Preparation.
               ------------

               (i)   Site Survey. Vendor will conduct site surveys in order to
                     identify site preparation which must be completed prior to
                     installation, special equipment requirements, interface
                     requirements, and the physical placement of equipment.

               (ii)  Inventory of Materials. Vendor will prepare inventories of
                     materials prior to installation of equipment at each site
                     identifying all components by common nomenclature, part
                     number, quantity required, and size or length, as
                     applicable.

               (iii) Equipment Staging. Vendor will stage and test all equipment
                     in a central location and then ship such equipment to the
                     appropriate site. Vendor will assemble, tag and stage for
                     shipping all equipment required for installation at the
                     site. Staging consists of assembling and testing pre-
                     configured interfaces and other components at the Vendor
                     facility.

               (iv)  Shipping. Vendor will arrange for shipping of the staged
                     equipment to the installation locations and ensure that all
                     equipment arrives at the installation sites prior to the
                     scheduled site visit date. Equipment scheduled for
                     installation by Vendor will be held at the site until the
                     Vendor installation team arrives to uncrate and install it.

               (v)   Installation. Vendor will install equipment onsite and
                     verify functionality according to specifications.
                     Installation includes the following activities:

                     (1)  Briefing site personnel;

                     (2)  Taking inventory of equipment and resolving
                          discrepancies;

                     (3)  Relocating equipment to footprint;

--------------------------------------------------------------------------------
Network Services Agreement     America Online, Inc./BBN Corporation CONFIDENTIAL
Schedule C                   Schedule C - Page 9
<PAGE>

                    CONFIDENTIAL TREATMENT REQUESTED

                    (4)  Bolting cabinets together (if applicable);

                    (5)  Installing intra-cabinet and inter-cabinet cables;

                    (6)  Connecting power and station ground;

                    (7)  Dressing and labeling cables, fantails, ports, and
                         mod-taps; and

                    (8)  Connecting to the network and ensuring operability.

          (c)  Maintenance.
               -----------

               (i)   Vendor will perform maintenance of equipment used to
                     provide the Broadband Backhaul Services based on input from
                     the monitoring systems and Customer. Vendor will handle
                     most [*Material Omitted and Separately Filed Under an
                     Application for Confidential Treatment] over the [*Material
                     Omitted and Separately Filed Under an Application for
                     Confidential Treatment] at the [*Material Omitted and
                     Separately Filed Under an Application for Confidential
                     Treatment] at the [*Material Omitted and Separately Filed
                     Under an Application for Confidential Treatment]
                     establishing working agreements with the [*Material Omitted
                     and Separately Filed Under an Application for Confidential
                     Treatment] and other [*Material Omitted and Separately
                     Filed Under an Application for Confidential Treatment] and
                     by providing written procedures.

               (ii)  Vendor will cooperate with Customer with respect to new
                     versions of software used to provide those services
                     provided by Customer that utilize the Broadband Backhaul
                     Services.

               (iii) Vendor shall reasonably coordinate with Customer regarding
                     any maintenance activity.

          (d)  Quality Control.
               ---------------

               Vendor will maintain a Quality Control Program to ensure all
               reasonable commercial standards applicable to Broadband Backhaul
               Services are adhered to.

     5.4. Management of Circuits.
          ----------------------

          Vendor will manage the [*Material Omitted and Separately Filed Under
          an Application for Confidential Treatment] necessary to meet
          [*Material Omitted and Separately Filed Under an Application for
          Confidential Treatment] outlined in this Schedule C. Vendor will
          utilize existing procedures and systems for [*Material Omitted and
          Separately Filed Under an Application for Confidential Treatment] as
          such may change from time to time. As part of the installation
          activities outlined above, Vendor will [*Material Omitted and
          Separately Filed Under an Application for Confidential Treatment].

--------------------------------------------------------------------------------
Network Services Agreement     America Online, Inc./BBN Corporation CONFIDENTIAL
Schedule C                   Schedule C - Page 10
<PAGE>

                     CONFIDENTIAL TREATMENT REQUESTED

     5.5. Operations.
          ----------

          Vendor will provision, staff and operate a NOC (currently in Columbia,
          Maryland) with dedicated support for Customer and a backup NOC at a
          separate location (such backup NOC is currently located in Chantilly,
          Virginia). Responsibilities of Vendor's operations support team
          include the following:

          (a)  Operation of the NOC and co-located systems with trained and
               qualified personnel on a continuous 24-hours-per-day,
               seven-days-per-week basis.

          (b)  Operation of all NOC equipment, monitoring, and fault isolation
               functions.

          (c)  Utilization of network management capabilities and Vendor
               diagnostic software resident in the NOC for:

               (i)   Monitoring [*Material Omitted and Separately Filed Under an
                     Application for Confidential Treatment].

               (ii)  Measuring [*Material Omitted and Separately Filed Under an
                     Application for Confidential Treatment] .

               (iii) Monitoring and recording [*Material Omitted and Separately
                     Filed Under an Application for Confidential Treatment].

               (iv)  Tracking the disposition of [*Material Omitted and
                     Separately Filed Under an Application for Confidential
                     Treatment].

          (d)  Coordination and management of field technicians for maintenance
               activities associated with the Vendor Network.

          (e)  Coordination and reporting of all support activities using a
               commercial trouble reporting system [*Material Omitted and
               Separately Filed Under an Application for Confidential
               Treatment].

          (f)  Support of short-term and long-term problem identification,
               analysis, and resolution.

          (g)  Identification and tracking of all software changes deployed in
               the Vendor Network and NOC platforms.

          (h)  Support for the deployment of new software and hardware (as
               coordinated with Customer).

          (i)  Provision of operational support to the Vendor Network for
               testing in association with provisioning activities.

          (j)  Maintenance of NOC maps.

--------------------------------------------------------------------------------
Network Services Agreement     America Online, Inc./BBN Corporation CONFIDENTIAL
Schedule C                   Schedule C - Page 11
<PAGE>

                       CONFIDENTIAL TREATMENT REQUESTED

          (k)  Coordination of Vendor Network change management activities and
               maintenance of authorized outage lists.

          (l)  Support of Customer in security matters in accordance with
               customary industry practices.

          (m)  Delivery of reports to pre-designated Customer representatives
               addressing the following:

               (i)   [*Material Omitted and Separately Filed Under an
                     Application for Confidential Treatment];

               (ii)  [*Material Omitted and Separately Filed Under an
                     Application for Confidential Treatment];

               (iii) [*Material Omitted and Separately Filed Under an
                     Application for Confidential Treatment];

               (iv)  [*Material Omitted and Separately Filed Under an
                     Application for Confidential Treatment];

               (v)   [*Material Omitted and Separately Filed Under an
                     Application for Confidential Treatment];

               (vi)  [*Material Omitted and Separately Filed Under an
                     Application for Confidential Treatment];

               (vii) Upon Customer's request, Vendor shall provide Customer with
                     [*Material Omitted and Separately Filed Under an
                     Application for Confidential Treatment] that are utilized
                     to provide Broadband Backhaul Services under this Schedule
                     C. In addition, for [*Material Omitted and Separately Filed
                     Under an Application for Confidential Treatment] that are
                     utilized to provide Broadband Backhaul Services under this
                     Schedule C, Vendor shall provide to Customer a daily report
                     covering the [*Material Omitted and Separately Filed Under
                     an Application for Confidential Treatment] as such data is
                     collected by Vendor. In the event of a Vendor Network
                     outage, Vendor will work cooperatively with Customer to
                     share additional [*Material Omitted and Separately Filed
                     Under an Application for Confidential Treatment] data which
                     may be pertinent to the resolution of any such outage, and,
                     upon Customer's reasonable request, Vendor will provide
                     [*Material Omitted and Separately Filed Under an
                     Application for Confidential Treatment]to assist in the
                     outage resolution. In the event of a Vendor Network
                     performance degradation, Vendor will work cooperatively
                     with Customer to share additional [*Material Omitted and
                     Separately Filed Under an Application for Confidential
                     Treatment] data which may be pertinent to the resolution of
                     any such degradation, and, upon Customer's reasonable
                     request, Vendor will provide [*Material Omitted and
                     Separately Filed Under an

--------------------------------------------------------------------------------
Network Services Agreement     America Online, Inc./BBN Corporation CONFIDENTIAL
Schedule C                   Schedule C - Page 12
<PAGE>

                       CONFIDENTIAL TREATMENT REQUESTED

                      Application for Confidential Treatment] to assist in the
                      problem resolution. All access by Customer will be
                      coordinated with Vendor in advance, and the polling
                      frequency for any device will be as the parties mutually
                      agree in advance for the [*Material Omitted and Separately
                      Filed Under an Application for Confidential Treatment];

               (viii) [*Material Omitted and Separately Filed Under an
                      Application for Confidential Treatment], including the
                      following:

                      (1)  [*Material Omitted and Separately Filed Under an
                           Application for Confidential Treatment];

                      (2)  [*Material Omitted and Separately Filed Under an
                           Application for Confidential Treatment];

                      (3)  [*Material Omitted and Separately Filed Under an
                           Application for Confidential Treatment];

                      (4)  [*Material Omitted and Separately Filed Under an
                           Application for Confidential Treatment];

                      (5)  [*Material Omitted and Separately Filed Under an
                           Application for Confidential Treatment];

                      (6)  [*Material Omitted and Separately Filed Under an
                           Application for Confidential Treatment];

                      (7)  [*Material Omitted and Separately Filed Under an
                           Application for Confidential Treatment];

                      (8)  [*Material Omitted and Separately Filed Under an
                           Application for Confidential Treatment];

                      (9)  [*Material Omitted and Separately Filed Under an
                           Application for Confidential Treatment];

                      (10) [*Material Omitted and Separately Filed Under an
                           Application for Confidential Treatment];

                      (11) [*Material Omitted and Separately Filed Under an
                           Application for Confidential Treatment]

                      (12) [*Material Omitted and Separately Filed Under an
                           Application for Confidential Treatment

               provided that Vendor shall provide Customer with weekly reports
               on [*Material Omitted and Separately Filed Under an Application
               for Confidential Treatment] sufficient to enable customer to
               determine [*Material Omitted and Separately Filed Under an
               Application for Confidential Treatment] in

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Network Services Agreement     America Online, Inc./BBN Corporation CONFIDENTIAL
Schedule C                   Schedule C - Page 13
<PAGE>

                       CONFIDENTIAL TREATMENT REQUESTED

               accordance with Section 8(a) of this Schedule C, and, as soon as
               technically feasible, Vendor shall provide such reports to
               Customer on a daily basis. Customer may periodically request
               additional reports that assist in improving network quality and
               analyzing [*Material Omitted and Separately Filed Under an
               Application for Confidential Treatment]. Vendor will provide
               these additional reports, or the raw data, subject to technical
               reasonableness.

     5.6. Aggregation Router Equipment.
          ----------------------------

          (a)  Aggregation router equipment used to provide the Broadband
               Backhaul Services shall be [*Material Omitted and Separately
               Filed Under an Application for Confidential Treatment] of
               Broadband Backhaul Services to Customer under this Agreement and
               shall not be [*Material Omitted and Separately Filed Under an
               Application for Confidential Treatment].

          (b)  Customer may specify the operating system features to be utilized
               for aggregation router equipment selected by Vendor and used to
               provide the Broadband Backhaul Services.

     5.7. Excluded Functions.
          ------------------

          Vendor shall not be responsible for providing the following with
          respect to the Broadband Backhaul Services:

          (a)  [*Material Omitted and Separately Filed Under an Application for
               Confidential Treatment];

          (b)  [*Material Omitted and Separately Filed Under an Application for
               Confidential Treatment];

          (c)  [*Material Omitted and Separately Filed Under an Application for
               Confidential Treatment];

          (d)  [*Material Omitted and Separately Filed Under an Application for
               Confidential Treatment].

6.   SERVICE LEVELS

     For each of the Service Levels set forth in this Article 6, scheduled
     maintenance by Vendor (or a third party) coordinated with Customer pursuant
     to Section 5.3(c)(i) of this Schedule C will be excluded from the Service
     Level performance calculations.

     6.1. Availability.
          ------------

          (a)  "Broadband Network Availability" for a calendar month is defined
               as the percentage calculated as (i) the total time in each month
               that [*Material Omitted and Separately Filed Under an Application
               for Confidential Treatment] is reachable through the [*Material
               Omitted and Separately Filed Under an Application for
               Confidential Treatment] from the [*Material

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Schedule C                   Schedule C - Page 14
<PAGE>

                       CONFIDENTIAL TREATMENT REQUESTED

               Omitted and Separately Filed Under an Application for
               Confidential Treatment] and vice-versa, divided by (ii) the sum
               of the total time in such month.

          (b)  The Service Level applicable to Broadband Network Availability
               for a calendar month shall be as follows: Broadband Network
               Availability for each calendar month shall exceed [*Material
               Omitted and Separately Filed Under an Application for
               Confidential Treatment] percent [*Material Omitted and Separately
               Filed Under an Application for Confidential Treatment]. Vendor
               shall provide Customer on a daily basis with reports on Broadband
               Network Availability, and Vendor's performance relative to such
               Service Level shall be measured on a monthly basis for each
               calendar month.

          (c)  In the event that Broadband Network Availability is below
               [*Material Omitted and Separately Filed Under an Application for
               Confidential Treatment] percent ([*Material Omitted and
               Separately Filed Under an Application for Confidential Treatment]
               %) as measured in [*Material Omitted and Separately Filed Under
               an Application for Confidential Treatment], such event shall
               constitute a material breach of the Agreement.

     6.2. Packet Loss.
          -----------

          (a)  "Broadband Packet Loss Percentage" means, for a calendar month,
               the quantity calculated as (i) the aggregate number of data
               packets dropped from the Vendor Network between the [*Material
               Omitted and Separately Filed Under an Application for
               Confidential Treatment], divided by (ii) the aggregate number of
               all data packets introduced into the Vendor Network between the
               [*Material Omitted and Separately Filed Under an Application for
               Confidential Treatment], during such month, the result expressed
               as a percentage.

          (b)  The Service Level applicable to Broadband Packet Loss Percentage
               shall be as follows: Broadband Packet Loss Percentage for each
               calendar month shall be less than or equal to [*Material Omitted
               and Separately Filed Under an Application for Confidential
               Treatment] percent ([*Material Omitted and Separately Filed Under
               an Application for Confidential Treatment]%) for such month.
               Vendor shall provide Customer on a daily basis with reports on
               Broadband Packet Loss Percentage, and Vendor's performance
               relative to such Service Level shall be measured on a monthly
               basis for each calendar month.

     6.3. Failed Sessions.

          (a)  "Failed Sessions" means point-to-point protocol sessions that are
               successfully placed to the [*Material Omitted and Separately
               Filed Under an Application for Confidential Treatment] and which
               do not fail as a result of problems with[*Material Omitted and
               Separately Filed Under an Application for Confidential
               Treatment].

          (b)  The Service Level applicable to Failed Sessions shall be that no
               more than [*Material Omitted and Separately Filed Under an
               Application for

--------------------------------------------------------------------------------
Network Services Agreement     America Online, Inc./BBN Corporation CONFIDENTIAL
Schedule C                   Schedule C - Page 15
<PAGE>

                       CONFIDENTIAL TREATMENT REQUESTED

               Confidential Treatment] percent ([*Material Omitted and
               Separately Filed Under an Application for Confidential
               Treatment]%) of [*Material Omitted and Separately Filed Under an
               Application for Confidential Treatment] that are successfully
               placed [*Material Omitted and Separately Filed Under an
               Application for Confidential Treatment] during the month shall be
               Failed Sessions. Vendor shall provide Customer on a daily basis
               with reports on Failed Sessions, and Vendor's performance
               relative to such Service Level shall be measured on a monthly
               basis for each calendar month.

     6.4. Abnormal Disconnects.

          (a)  "Broadband Abnormal Disconnect Percentage" means, for each
               calendar day of the Broadband Term, the amount calculated as (i)
               the aggregate number of disconnected sessions utilizing the
               Broadband Backhaul Services during such day that are not
               initiated by a user logoff sequence and that are caused by
               problems in the network between [*Material Omitted and Separately
               Filed Under an Application for Confidential Treatment], divided
               by (ii) the aggregate number of all sessions utilizing the
               Broadband Backhaul Services commencing during such calendar day,
               with the result expressed as a percentage. "Monthly Broadband
               Abnormal Disconnect Percentage" means, for each calendar month of
               the Broadband Term, the amount calculated as (x) the
               percentage-point aggregate of the Broadband Abnormal Disconnect
               Percentages for such calendar month, divided by (y) the aggregate
               number of calendar days in such calendar month.

          (b)  The Service Level applicable to Monthly Broadband Abnormal
               Disconnect Percentage shall be as follows: Monthly Broadband
               Abnormal Disconnect Percentage during a calendar month shall not
               exceed [*Material Omitted and Separately Filed Under an
               Application for Confidential Treatment] percent ([*Material
               Omitted and Separately Filed Under an Application for
               Confidential Treatment]%). Vendor's performance relative to such
               Service Level shall be reported by Customer on a monthly basis
               for each calendar month, if technically feasible.

     6.5. Failure to Perform.

          (a)  If Vendor fails to meet any Service Level, Vendor shall (i)
               promptly notify Customer of such failure (unless Customer first
               discovered and notified Vendor of such failure), (ii) investigate
               and report on the causes of the failure; (iii) advise Customer,
               as and to the extent requested by Customer, of the status of
               remedial efforts being undertaken with respect to such failure;
               (iv) take commercially reasonable efforts to correct the failure,
               and begin meeting the Service Levels; and (v) take appropriate
               preventive measures to minimize the likelihood of the failure
               recurring.

          (b)  Notwithstanding the foregoing, Vendor's failure to meet or
               correct Service Level failures under this Schedule C during the
               first six months following the Effective Date shall not
               constitute a breach of the Agreement.

--------------------------------------------------------------------------------
Network Services Agreement     America Online, Inc./BBN Corporation CONFIDENTIAL
Schedule C                   Schedule C - Page 16
<PAGE>

                       CONFIDENTIAL TREATMENT REQUESTED

          (c)  Notwithstanding the foregoing, Vendor's failure to use
               commercially reasonable efforts to meet or correct Service Level
               failures with respect to the Abnormal Disconnects in and of
               itself shall not constitute a breach of the Agreement.

          (d)  Vendor shall not be deemed in breach of such Service Levels to
               the extent that such breach is attributable to the offered data
               load from Customer data centers or subscribers exceeding the
               specified bandwidth per user or Customer having oversubscribed
               the intra-LATA interconnect circuits.

          (e)  Notwithstanding anything to the contrary to this Agreement, under
               no circumstances shall Customer be permitted to terminate any
               portion of the Agreement other than this Schedule C as a result
               of any material breaches, whether cured or uncured, of the
               Service Levels in this Schedule C.

     6.6. Meetings.
          --------

          Vendor and Customer shall hold weekly meetings at Customer's site or
          via telephone conference call (unless otherwise requested by Customer)
          to assess Vendor's performance under this Schedule C. During emergency
          situations, meetings will be held at least on a daily basis.

     6.7. Periodic Review of Service Levels.
          ---------------------------------

          As requested by Customer or Vendor, Customer and Vendor shall review
          the Service Levels described in this Schedule C and shall make
          mutually agreed-upon adjustments to them as appropriate to reflect
          performance capabilities associated with advances in the technology
          and methods used to provide the Broadband Backhaul Services.

7.   PRICING

     7.1. Charges for Broadband Backhaul Services.
          ---------------------------------------

          (a)  The monthly charges for the Broadband Backhaul Services shall be
               computed as the applicable Monthly Aggregate Subscriber Line
               Charges calculated pursuant to Exhibit C-2 plus the Monthly
               Pass-Through Expenses calculated pursuant to Subsection (b) of
               this Section.

          (b)  Monthly Pass-Through Expenses.
               -----------------------------

               (i)  "Monthly Pass-Through Expenses" means the following
                    third-party charges incurred by Vendor to provide the
                    Broadband Backhaul Services (including Broadband Backhaul
                    Services not yet accepted by Customer) during a calendar
                    month of the Broadband Term, for which Customer shall
                    reimburse Vendor on an Out-of-Pocket Expenses basis:

                    (1)  Third-party charges for the [*Material Omitted and
                         Separately Filed Under an Application for Confidential
                         Treatment] is necessary to provide the Broadband
                         Backhaul Services; and

--------------------------------------------------------------------------------
Network Services Agreement     America Online, Inc./BBN Corporation CONFIDENTIAL
Schedule C                   Schedule C - Page 17
<PAGE>

                     (2)  Third-party charges approved in advance by Customer
                          for the acquisition of hub equipment at Customer's
                          facilities.

               (ii)  Vendor shall act as payment agent for Customer with respect
                     to the Monthly Pass-Through Expenses and shall pay the
                     corresponding third-party charges comprising the Monthly
                     Pass-Through Expenses.

               (iii) Vendor shall use commercially reasonable efforts to
                     minimize the amount of Monthly Pass-Through Expenses, by
                     among other means identifying and considering multiple
                     sources for the services and materials corresponding to
                     such expenses.

     7.2. Adjustments to Pricing for Services.
          -----------------------------------

          (a)  Broadband Backhaul Market Price.
               --------------------------------

               (i)  Definitions.

                    (1)  "New Broadband Backhaul Market Price" shall mean the
                         price (or, if applicable, prices and corresponding
                         volumes) [*Material Omitted and Separately Filed Under
                         an Application for Confidential Treatment] by any
                         [*Material Omitted and Separately Filed Under an
                         Application for Confidential Treatment]. To calculate
                         the New Broadband Backhaul Market Price pursuant to
                         this Subsection, the price for Comparable Broadband
                         Backhaul Services shall be reasonably adjusted to
                         reflect the difference between [*Material Omitted and
                         Separately Filed Under an Application for Confidential
                         Treatment] and the provision of [*Material Omitted and
                         Separately Filed Under an Application for Confidential
                         Treatment] by a [*Material Omitted and Separately Filed
                         Under an Application for Confidential Treatment] that
                         (A) do not [*Material Omitted and Separately Filed
                         Under an Application for Confidential Treatment],or (B)
                         do not [*Material Omitted and Separately Filed Under an
                         Application for Confidential Treatment].

                    (2)  "Broadband Backhaul Market Vendor" shall mean a vendor
                         (not including a Special Affiliate) that at any time
                         [*Material Omitted and Separately Filed Under an
                         Application for Confidential Treatment]. For the
                         purpose of this Subsection, Special Affiliate shall
                         only be deemed to include Subsections (i) and (ii) of
                         the definition of "Special Affiliate" in Schedule A.

               (ii) Notification Process.

                    Customer may provide Vendor with notice at any time of a New
                    Broadband Backhaul Market Price (each such notice, a "New
                    Broadband Backhaul Market Price Notice" and the date of such

--------------------------------------------------------------------------------
Network Services Agreement     America Online, Inc./BBN Corporation CONFIDENTIAL
Schedule C                   Schedule C - Page 18
<PAGE>

                       CONFIDENTIAL TREATMENT REQUESTED

                    notice as determined pursuant to Section 16.4 of the Master
                    Agreement, the "New Broadband Backhaul Market Price Notice
                    Date"). Each New Broadband Backhaul Market Price Notice will
                    contain (A) the New Broadband Backhaul Market Price
                    calculation and [*Material Omitted and Separately Filed
                    Under an Application for Confidential Treatment] of the
                    [*Material Omitted and Separately Filed Under an Application
                    for Confidential Treatment] to which such [*Material Omitted
                    and Separately Filed Under an Application for Confidential
                    Treatment] relates, and (B) information sufficient to enable
                    [*Material Omitted and Separately Filed Under an Application
                    for Confidential Treatment] per [*Material Omitted and
                    Separately Filed Under an Application for Confidential
                    Treatment] at [*Material Omitted and Separately Filed Under
                    an Application for Confidential Treatment] corresponding to
                    the [*Material Omitted and Separately Filed Under an
                    Application for Confidential Treatment] if requested by
                    customer. No later than thirty (30) calendar days after the
                    Broadband Backhaul Market Price Notice Date corresponding to
                    a New Broadband Backhaul Market Price Notice, Vendor will
                    respond to Customer by notifying Customer in writing whether
                    it will:

                    (1)  accept the validity of the proposed New Broadband
                         Backhaul Market Price and reduce prices to the
                         applicable New Broadband Backhaul Market Price in
                         accordance with Subsection (iii) of this Subsection
                         (a),

                    (2)  accept the validity of the proposed New Broadband
                         Backhaul Market Price and decline to reduce prices to
                         the New Broadband Backhaul Market Price in accordance
                         with Subsection (iii) of this Subsection (a), or

                    (3)  dispute the validity of the proposed New Broadband
                         Backhaul Market Price

                    (each a "New Broadband Backhaul Market Price Response").
                    Vendor shall not unreasonably dispute the validity of a
                    proposed New Broadband Backhaul Market Price.

              (iii) Reduction Process.

                    In the event Vendor accepts a proposed New Broadband
                    Backhaul Market Price pursuant to clause (1) of Subsection
                    (ii) of this Subsection (a), then effective as of the later
                    of (a) the New Broadband Backhaul Market Price Effective
                    Date corresponding to such New Broadband Backhaul Market
                    Price Notice, and (b) [*Material Omitted and Separately
                    Filed Under an Application for Confidential Treatment], the
                    Monthly Per Subscriber Line Charge will be reduced to the
                    New Broadband Backhaul Market Price set forth in the
                    corresponding New Broadband Backhaul Market Price Notice,
                    and with respect to such

--------------------------------------------------------------------------------
Network Services Agreement     America Online, Inc./BBN Corporation CONFIDENTIAL
Schedule C                   Schedule C - Page 19
<PAGE>

                       CONFIDENTIAL TREATMENT REQUESTED

                    Broadband Backhaul Services, Vendor will, if requested by
                    Customer, [*Material Omitted and Separately Filed Under an
                    Application for Confidential Treatment] per [*Material
                    Omitted and Separately Filed Under an Application for
                    Confidential Treatment] at [*Material Omitted and Separately
                    Filed Under an Application for Confidential Treatment] or
                    the [*Material Omitted and Separately Filed Under an
                    Application for Confidential Treatment] corresponding to
                    such New Broadband Backhaul Market Price; provided, however,
                    that Vendor shall not be obligated to reduce the Monthly Per
                    Subscriber Line Charge [*Material Omitted and Separately
                    Filed Under an Application for Confidential Treatment] for
                    which Vendor reduced prices pursuant to this Subsection
                    (iii).

                    Notwithstanding the foregoing:

                    (1)  Vendor shall not be obligated to reduce the Monthly Per
                         Subscriber Line Charge at a rate that is more rapid
                         than the rate at which the [*Material Omitted and
                         Separately Filed Under an Application for Confidential
                         Treatment] provides Customer with [*Material Omitted
                         and Separately Filed Under an Application for
                         Confidential Treatment] relative to the applicable
                         [*Material Omitted and Separately Filed Under an
                         Application for Confidential Treatment], as measured
                         monthly.

                    Example 1 - Straight Percentage Commitment: For example, if
                    the [*Material Omitted and Separately Filed Under an
                    Application for Confidential Treatment] has committed to
                    provide [*Material Omitted and Separately Filed Under an
                    Application for Confidential Treatment] with [*Material
                    Omitted and Separately Filed Under an Application for
                    Confidential Treatment] for [*Material Omitted and
                    Separately Filed Under an Application for Confidential
                    Treatment] or more of the [*Material Omitted and Separately
                    Filed Under an Application for Confidential Treatment] (in
                    terms of a percentage commitment) at the [*Material Omitted
                    and Separately Filed Under an Application for Confidential
                    Treatment], but immediately following the [*Material Omitted
                    and Separately Filed Under an Application for Confidential
                    Treatment] has only provided [*Material Omitted and
                    Separately Filed Under an Application for Confidential
                    Treatment] with [*Material Omitted and Separately Filed
                    Under an Application for Confidential Treatment] for
                    [*Material Omitted and Separately Filed Under an Application
                    for Confidential Treatment] percent [*Material Omitted and
                    Separately Filed Under an Application for Confidential
                    Treatment] of the [*Material Omitted and Separately Filed
                    Under an Application for Confidential Treatment] at the
                    [*Material Omitted and Separately Filed Under an Application
                    for Confidential Treatment], then Vendor will only be
                    obligated to reduce the Monthly Per Subscriber

--------------------------------------------------------------------------------
Network Services Agreement     America Online, Inc./BBN Corporation CONFIDENTIAL
Schedule C                   Schedule C - Page 20
<PAGE>

                    CONFIDENTIAL TREATMENT REQUESTED

                    Line Charge for [*Material Omitted and Separately Filed
                    Under an Application for Confidential Treatment] percent
                    [*Material Omitted and Separately Filed Under an Application
                    for Confidential Treatment] of the [*Material Omitted and
                    Separately Filed Under an Application for Confidential
                    Treatment] as of the applicable month. If during the
                    following month the [*Material Omitted and Separately Filed
                    Under an Application for Confidential Treatment] has
                    provided [*Material Omitted and Separately Filed Under an
                    Application for Confidential Treatment] for an additional
                    [*Material Omitted and Separately Filed Under an Application
                    for Confidential Treatment] percent [*Material Omitted and
                    Separately Filed Under an Application for Confidential
                    Treatment] of the [*Material Omitted and Separately Filed
                    Under an Application for Confidential Treatment] at the
                    [*Material Omitted and Separately Filed Under an Application
                    for Confidential Treatment], then Vendor will be obligated
                    to reduce the Monthly Per Subscriber Line Charge for
                    [*Material Omitted and Separately Filed Under an Application
                    for Confidential Treatment] percent [*Material Omitted and
                    Separately Filed Under an Application for Confidential
                    Treatment] of the [*Material Omitted and Separately Filed
                    Under an Application for Confidential Treatment] as of the
                    applicable month.

                    Example 2 - Actual Volume Commitment: For example, if,
                    instead, the [*Material Omitted and Separately Filed Under
                    an Application for Confidential Treatment] has committed to
                    provide [*Material Omitted and Separately Filed Under an
                    Application for Confidential Treatment] with [*Material
                    Omitted and Separately Filed Under an Application for
                    Confidential Treatment] for [*Material Omitted and
                    Separately Filed Under an Application for Confidential
                    Treatment] at the [*Material Omitted and Separately Filed
                    Under an Application for Confidential Treatment] and at the
                    time that [*Material Omitted and Separately Filed Under an
                    Application for Confidential Treatment] provides [*Material
                    Omitted and Separately Filed Under an Application for
                    Confidential Treatment] with the [*Material Omitted and
                    Separately Filed Under an Application for Confidential
                    Treatment] is [*Material Omitted and Separately Filed Under
                    an Application for Confidential Treatment], then the
                    [*Material Omitted and Separately Filed Under an Application
                    for Confidential Treatment] has been met because it meets
                    the [*Material Omitted and Separately Filed Under an
                    Application for Confidential Treatment]. If as of the New
                    Broadband Backhaul Market Price Effective Date, such
                    [*Material Omitted and Separately Filed Under an Application
                    for Confidential Treatment] has provided [*Material Omitted
                    and Separately Filed Under an Application for Confidential
                    Treatment] with [*Material Omitted and Separately Filed
                    Under an Application for Confidential Treatment] for
                    [*Material Omitted and Separately Filed Under an Application
                    for Confidential Treatment] of the [*Material Omitted

--------------------------------------------------------------------------------
Network Services Agreement     America Online, Inc./BBN Corporation CONFIDENTIAL
Schedule C                   Schedule C - Page 21
<PAGE>

                       CONFIDENTIAL TREATMENT REQUESTED

                    and Separately Filed Under an Application for Confidential
                    Treatment] committed [*Material Omitted and Separately Filed
                    Under an Application for Confidential Treatment] at the
                    [*Material Omitted and Separately Filed Under an Application
                    for Confidential Treatment] but [*Material Omitted and
                    Separately Filed Under an Application for Confidential
                    Treatment] has grown to [*Material Omitted and Separately
                    Filed Under an Application for Confidential Treatment], then
                    Vendor will only be obligated to reduce the Monthly Per
                    Subscriber Line Charge for [*Material Omitted and Separately
                    Filed Under an Application for Confidential Treatment]
                    percent [*Material Omitted and Separately Filed Under an
                    Application for Confidential Treatment] of the [*Material
                    Omitted and Separately Filed Under an Application for
                    Confidential Treatment] as of the applicable month (i.e.,
                    because the [*Material Omitted and Separately Filed Under an
                    Application for Confidential Treatment] being serviced by
                    the [*Material Omitted and Separately Filed Under an
                    Application for Confidential Treatment] only represents
                    [*Material Omitted and Separately Filed Under an Application
                    for Confidential Treatment]. If in the following month,
                    [*Material Omitted and Separately Filed Under an Application
                    for Confidential Treatment] has provided [*Material Omitted
                    and Separately Filed Under an Application for Confidential
                    Treatment] with [*Material Omitted and Separately Filed
                    Under an Application for Confidential Treatment] for all
                    [*Material Omitted and Separately Filed Under an Application
                    for Confidential Treatment] at the [*Material Omitted and
                    Separately Filed Under an Application for Confidential
                    Treatment] and [*Material Omitted and Separately Filed Under
                    an Application for Confidential Treatment] has remained at
                    [*Material Omitted and Separately Filed Under an Application
                    for Confidential Treatment], then Vendor will be obligated
                    to reduce the Monthly Per Subscriber Line Charge for
                    [*Material Omitted and Separately Filed Under an Application
                    for Confidential Treatment] of the [*Material Omitted and
                    Separately Filed Under an Application for Confidential
                    Treatment] as of such month (i.e., because the [*Material
                    Omitted and Separately Filed Under an Application for
                    Confidential Treatment] being serviced by the [*Material
                    Omitted and Separately Filed Under an Application for
                    Confidential Treatment]. If in following month, [*Material
                    Omitted and Separately Filed Under an Application for
                    Confidential Treatment] has provided [*Material Omitted and
                    Separately Filed Under an Application for Confidential
                    Treatment] for an aggregate [*Material Omitted and
                    Separately Filed Under an Application for Confidential
                    Treatment], then Vendor will be obligated to reduce the
                    Monthly Per Subscriber Line Charge [*Material Omitted and
                    Separately Filed Under an Application for Confidential
                    Treatment] of the [*Material Omitted and Separately Filed
                    Under an Application for Confidential Treatment] as of such
                    month (because the [*Material Omitted and Separately Filed
                    Under an Application for Confidential Treatment]

--------------------------------------------------------------------------------
Network Services Agreement     America Online, Inc./BBN Corporation CONFIDENTIAL
Schedule C                   Schedule C - Page 22
<PAGE>

                       CONFIDENTIAL TREATMENT REQUESTED

                    being serviced by the [*Material Omitted and Separately
                    Filed Under an Application for Confidential Treatment]. If
                    in the following month, [*Material Omitted and Separately
                    Filed Under an Application for Confidential Treatment] has
                    provided [*Material Omitted and Separately Filed Under an
                    Application for Confidential Treatment] for the same
                    aggregate [*Material Omitted and Separately Filed Under an
                    Application for Confidential Treatment] at the [*Material
                    Omitted and Separately Filed Under an Application for
                    Confidential Treatment] and [*Material Omitted and
                    Separately Filed Under an Application for Confidential
                    Treatment] has grown to [*Material Omitted and Separately
                    Filed Under an Application for Confidential Treatment] there
                    will be no reduction in the percentage of [*Material Omitted
                    and Separately Filed Under an Application for Confidential
                    Treatment] which have the [*Material Omitted and Separately
                    Filed Under an Application for Confidential Treatment].

                    (2)  Vendor shall not be obligated [*Material Omitted and
                         Separately Filed Under an Application for Confidential
                         Treatment] provides [*Material Omitted and Separately
                         Filed Under an Application for Confidential Treatment]
                         relative to the applicable [*Material Omitted and
                         Separately Filed Under an Application for Confidential
                         Treatment], as measured monthly.

                    (3)  A New Broadband Backhaul Market Price shall be
                         applicable only during such periods as [*Material
                         Omitted and Separately Filed Under an Application for
                         Confidential Treatment] actually [*Material Omitted and
                         Separately Filed Under an Application for Confidential
                         Treatment], or a lower price, from a [*Material Omitted
                         and Separately Filed Under an Application for
                         Confidential Treatment].

               (iv) Decommissioning Process.

                    If Vendor declines to reduce the Monthly Per Subscriber Line
                    Charge to the New Broadband Backhaul Market Price pursuant
                    to clause (2) of Subsection (ii) of this Subsection (a),
                    then Customer may, in its sole discretion, do either or both
                    of the following: (A) terminate the Broadband Backhaul
                    Purchase Commitment, and (B) disconnect Vendor Broadband
                    Subscriber Lines from the Vendor Network, subject to the
                    following restrictions:

                    (1)  Customer will provide [*Material Omitted and Separately
                         Filed Under an Application for Confidential Treatment]
                         days prior written notice of the LATA or other
                         geographic area in which Vendor Broadband Subscriber
                         Lines are to be disconnected from the Vendor Network,
                         as well as the

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Network Services Agreement     America Online, Inc./BBN Corporation CONFIDENTIAL
Schedule C                    Schedule C - Page 23
<PAGE>

                       CONFIDENTIAL TREATMENT REQUESTED

                         associated quantities of Vendor Broadband Subscriber
                         Lines to be disconnected in each such LATA or other
                         geographic area.

                    (2)  Customer may not order the disconnection of Vendor
                         Broadband Backhaul Subscriber Lines from the Vendor
                         Network in amounts greater than the number of the
                         Aggregate Subscriber Lines utilizing Comparable
                         Broadband Backhaul Services that are provided to
                         Customer by other entities at or below such New
                         Broadband Backhaul Market Price.

                    (3)  The disconnection of Vendor Broadband Subscriber Lines
                         from the Vendor Network pursuant to this Subsection
                         7.2(a)(iv) shall result in the same approximate
                         weighted distribution of Vendor Broadband Subscriber
                         Lines across all Existing LATAs. For the purposes of
                         this Subsection (3), "distribution" means the
                         distribution of the corresponding Subscriber Lines
                         across rural versus urban areas, across the contiguous
                         states of the United States, and between Covered
                         Subscriber Lines and non-Covered Subscriber Lines.

               (v)  Dispute Resolution Process.

                    If Vendor reasonably disputes the validity of the New
                    Broadband Backhaul Market Price pursuant to clause (3) of
                    Subsection (ii) of this Subsection (a), then each Party
                    shall promptly escalate to the senior-executive level all
                    efforts by such Party to resolve such dispute.

          (b)  Most-Favored Customer.
               ---------------------

               (i)  As long as the aggregate number of Vendor Broadband
                    Subscriber Lines exceeds that of any other customer of
                    Vendor, Vendor shall not provide Comparable Broadband
                    Backhaul Services to any other Applicable BB Purchaser (1)
                    at prices that are lower than those charged or available to
                    Customer under this Agreement, or (2) pursuant to terms and
                    conditions more favorable to such Applicable BB Purchaser
                    than the terms and conditions of this Schedule C and Master
                    Agreement, in each case, without offering such lower price
                    and other more favorable terms and conditions to Customer
                    within thirty (30) calendar days of contractually committing
                    to such price and other terms with another customer. For the
                    purposes of this Subsection, prices "charged or available to
                    Customer under this Agreement" for Broadband Backhaul
                    Services shall be a [*Material Omitted and Separately Filed
                    Under an Application for Confidential Treatment] of all
                    [*Material Omitted and Separately Filed Under an Application
                    for Confidential Treatment] hereunder. In the event that the
                    aggregate number of Vendor Broadband Subscriber Lines then
                    being purchased or ordered by Customer at any time during
                    the Broadband Term exceeds that of any other customer of
                    Vendor, Vendor shall provide Customer with written
                    notification of such

--------------------------------------------------------------------------------
Network Services Agreement     America Online, Inc./BBN Corporation CONFIDENTIAL
Schedule C                    Schedule C - Page 24
<PAGE>

                       CONFIDENTIAL TREATMENT REQUESTED

                    event within thirty (30) calendar days of the occurrence of
                    such event, and thereafter, once the aggregate number of
                    Vendor Broadband Subscriber Lines then being purchased or
                    ordered by Customer falls below that of any other customer
                    of Vendor, Vendor shall provide Customer with written
                    notification of such event within thirty (30) calendar days
                    of the occurrence of such event. "Applicable BB Purchaser"
                    shall mean any party (including any Vendor Affiliate that
                    resells Broadband Backhaul Services purchased from Vendor)
                    that is obligated to purchase, that actually purchases, or
                    that seeks to purchase from Vendor Broadband Backhaul
                    Services at any time for more than the Applicable BB Volume
                    for the then-current calendar year. "Applicable BB Volume"
                    means (A) [*Material Omitted and Separately Filed Under an
                    Application for Confidential Treatment] subscriber lines,
                    (B) [*Material Omitted and Separately Filed Under an
                    Application for Confidential Treatment] subscriber lines,
                    (C) [*Material Omitted and Separately Filed Under an
                    Application for Confidential Treatment] subscriber lines,
                    (D) [*Material Omitted and Separately Filed Under an
                    Application for Confidential Treatment] subscriber lines,
                    and (E) [*Material Omitted and Separately Filed Under an
                    Application for Confidential Treatment] subscriber lines.

              (ii)  As long as the aggregate number of Vendor Broadband
                    Subscriber Lines exceeds that of any other customer of
                    Vendor, to the extent that Vendor provides broadband
                    backhaul services that are not Comparable Broadband Backhaul
                    Services, then Vendor shall offer, on a quarterly basis, to
                    provide to Customer such broadband backhaul services at the
                    prices charged or available to, and upon the terms and
                    conditions applicable to, any Applicable BB Purchaser;
                    provided, however, that if Customer's service requirements
                    would necessitate changes to such terms and conditions, the
                    Parties shall work in good faith to adjust such terms and
                    conditions as mutually agreed to satisfy such requirements.
                    To the extent that Customer accepts such offer of broadband
                    backhaul services that are not Comparable Broadband Backhaul
                    Services from Vendor, Vendor shall provide such services
                    pursuant to a separate Schedule to the Master Agreement,
                    such services shall be deemed Services to which the Master
                    Agreement applies, and such services shall be subject to
                    most-favored customer terms and conditions substantially
                    similar to those set forth in this Subsection (b), and any
                    such services will contribute toward [*Material Omitted and
                    Separately Filed Under an Application for Confidential
                    Treatment] on an equitable basis. For purposes of this
                    Subsection (ii), broadband backhaul services that are not
                    Comparable Broadband Backhaul Services include, but are not
                    limited to, an end-to-end broadband service which includes
                    the local loop, and usage-based broadband backhaul services.

              (iii) As long as the aggregate number of Vendor Subscriber Lines
                    exceeds that of any other customer of Vendor, Vendor shall
                    offer to Customer

--------------------------------------------------------------------------------
Network Services Agreement     America Online, Inc./BBN Corporation CONFIDENTIAL
Schedule C                    Schedule C - Page 25
<PAGE>

                    CONFIDENTIAL TREATMENT REQUESTED

                    Comparable Broadband Backhaul Services provided or offered
                    by any Vendor Affiliate to an Applicable BB Purchaser (1) at
                    prices that are equal to or lower than those charged or
                    available to such Applicable BB Purchaser for such services,
                    and (2) pursuant to terms and conditions that are at least
                    as favorable to Customer than the terms and conditions
                    applicable to or available to an Applicable BB Purchaser.

               (iv) For any price proposal made by Vendor to Customer at any
                    time during the Term, Vendor shall in good faith represent
                    to Customer in writing whether or not such proposal is being
                    made for reasons that include Vendor's belief that an
                    adjustment may be required pursuant to this Subsection (b).

               (v)  Customer may audit Vendor's compliance with this Subsection
                    (b) pursuant to Article 10 of the Master Agreement. In the
                    event that Vendor fails to comply with this Subsection (b)
                    (e.g., fails to adjust pricing in accordance with this
                    Subsection (b)), then Vendor shall rebate to Customer, with
                    respect to the aggregate volume of Broadband Backhaul
                    Services purchased hereunder, the difference between (1) the
                    price actually paid by Customer hereunder, and (2) the lower
                    price provided to the Applicable BB Purchaser, retroactive
                    to the date Vendor committed to provide the lower price to
                    such Applicable BB Purchaser, together with interest
                    computed in the same manner as described in Section 9.2 of
                    the Master Agreement on such rebated amounts from such date.

8.   SPECIFICATIONS

     The Broadband Backhaul Services provided hereunder shall fully conform with
     the following Specifications (collectively, the "Broadband
     Specifications"):

          (a)  Vendor will provision end-to-end bandwidth such that [*Material
               Omitted and Separately Filed Under an Application for
               Confidential Treatment]. For each [*Material Omitted and
               Separately Filed Under an Application for Confidential Treatment]
               Line that Customer requests Vendor to provide hereunder, Vendor
               shall provide [*Material Omitted and Separately Filed Under an
               Application for Confidential Treatment] at a charge to Customer
               that is no greater than [*Material Omitted and Separately Filed
               Under an Application for Confidential Treatment] cents
               ($[*Material Omitted and Separately Filed Under an Application
               for Confidential Treatment]) [*Material Omitted and Separately
               Filed Under an Application for Confidential Treatment].

          (b)  Each circuit used to provide Broadband Backhaul Services between
               the Vendor Network and Customer's facilities shall have capacity
               equal to or greater than DS-3.

--------------------------------------------------------------------------------
Network Services Agreement     America Online, Inc./BBN Corporation CONFIDENTIAL
Schedule C                    Schedule C - Page 26
<PAGE>

                       CONFIDENTIAL TREATMENT REQUESTED

          (c)  Aggregation router equipment will be fully compliant with (i)
               [*Material Omitted and Separately Filed Under an Application for
               Confidential Treatment],and (ii) [*Material Omitted and
               Separately Filed Under an Application for Confidential Treatment]
               for [*Material Omitted and Separately Filed Under an Application
               for Confidential Treatment] set forth in [*Material Omitted and
               Separately Filed Under an Application for Confidential Treatment]
               effective [*Material Omitted and Separately Filed Under an
               Application for Confidential Treatment], as such referenced
               specifications may change from time to time, provided that Vendor
               shall not be required to replace aggregation router equipment to
               meet any changed specifications, but shall be required to
               implement any software provided by the manufacturer of such
               aggregation router equipment within a commercially reasonable
               period of time after such software is provided and after
               successful testing by Vendor.

          (d)  If Vendor changes aggregation router equipment, it will be fully
               functional with services provided by Customer without
               modification of, or addition to, client or host software used to
               provide services provided by Customer that utilize the Broadband
               Backhaul Services. As of the Effective Date, aggregation router
               equipment must comply with the following protocol requirements in
               order to comply with the requirements of this Subsection (d):

               (i)  [*Material Omitted and Separately Filed Under an Application
                    for Confidential Treatment] ; and

               (ii) [*Material Omitted and Separately Filed Under an Application
                    for Confidential Treatment].

          (e)  The Broadband Backhaul Services will support the following
               software features being developed for Customer[*Material Omitted
               and Separately Filed Under an Application for Confidential
               Treatment] as of the Effective Date:

               (i)   [*Material Omitted and Separately Filed Under an
                     Application for Confidential Treatment] ;

               (ii)  [*Material Omitted and Separately Filed Under an
                     Application for Confidential Treatment];

               (iii) [*Material Omitted and Separately Filed Under an
                     Application for Confidential Treatment];

               (iv)  [*Material Omitted and Separately Filed Under an
                     Application for Confidential Treatment];

               (v)   [*Material Omitted and Separately Filed Under an
                     Application for Confidential Treatment];

               (vi)  [*Material Omitted and Separately Filed Under an
                     Application for Confidential Treatment];

--------------------------------------------------------------------------------
Network Services Agreement     America Online, Inc./BBN Corporation CONFIDENTIAL
Schedule C                    Schedule C - Page 27
<PAGE>

                       CONFIDENTIAL TREATMENT REQUESTED

               (vii)  [*Material Omitted and Separately Filed Under an
                      Application for Confidential Treatment];

               (viii) [*Material Omitted and Separately Filed Under an
                      Application for Confidential Treatment];

               (ix)   [*Material Omitted and Separately Filed Under an
                      Application for Confidential Treatment];

               (x)    [*Material Omitted and Separately Filed Under an
                      Application for Confidential Treatment]

               (xi)   [*Material Omitted and Separately Filed Under an
                      Application for Confidential Treatment].

               The Parties acknowledge and agree that as of the Effective Date,
               the Redback Networks Inc. ("Redback") router aggregation
               equipment utilized to provide the Broadband Backhaul Services as
               of the Effective Date satisfy the Broadband Specifications set
               forth in Subsections (c) and (d) of this Article 8. The Broadband
               Backhaul Services will support any additional software features
               provided by the aggregation router vendor after the Effective
               Date as mutually agreed by the Parties. Vendor shall use
               commercially reasonable efforts to cause [*Material Omitted and
               Separately Filed Under an Application for Confidential Treatment]
               to provide those features described in this Subsection (e).

          (f)  Any Broadband Backhaul Market Vendor shall support the Broadband
               Specifications set forth in Subsections (c), (d) and (e) of this
               Article 8 in a manner comparable to that required of Vendor
               pursuant to such Subsections.

          The Parties acknowledge and agree that this Article 8 does not set
          forth a complete listing of required specifications applicable to
          Broadband Backhaul Services that are used to provide any non-xDSL
          services. Any such specifications not set forth in this Article 8
          shall be mutually agreed upon by the Parties pursuant to Article 2 of
          this Schedule C.

9.   LIABILITY RESTRICTIONS

          (a)  Subject to Subsection (d) of this Section, the liability of
               Vendor to Customer for all damages arising out of or related to
               the Services provided under this Schedule will be limited to, and
               will not exceed, in the aggregate during any calendar year, ten
               percent (10%) of the aggregate amounts paid to Vendor by Customer
               (excluding Out-of-Pocket Expenses and Monthly Pass-Through
               Expenses) under this Schedule during the twelve (12) month period
               preceding the date of the event giving rise to such damages;
               provided, however, for the initial twelve (12) months following
               the Effective Date, the foregoing cap shall be no less than Five
               Million Dollars ($5,000,000). Subject to Subsections (b) and (d)
               of this Section, the liability of Vendor to Customer for damages
               arising out of or related

--------------------------------------------------------------------------------
Network Services Agreement     America Online, Inc./BBN Corporation CONFIDENTIAL
Schedule C                    Schedule C - Page 28
<PAGE>

                       CONFIDENTIAL TREATMENT REQUESTED

               to Services provided under this Schedule caused by the acts or
               omissions of third parties beyond the reasonable control of
               Vendor will be further limited and will not exceed, in the
               aggregate during any calendar year, the lesser of (i) five
               percent (5%) of the aggregate amounts paid to Vendor by Customer
               (excluding Out-of-Pocket Expenses and Monthly Pass-Through
               Expenses) under this Schedule during the twelve (12) month period
               preceding the date of the event giving rise to such damages, or
               (ii) Ten Million Dollars ($10,000,000); provided, however, for
               the initial twelve (12) months following the Effective Date, the
               foregoing cap shall be no less than Three Million Dollars
               ($3,000,000).

          (b)  In the event of any liability of Vendor to Customer for damages
               arising out of or related to Services provided under this
               Schedule caused by the acts or omissions of third parties beyond
               the reasonable control of Vendor, then the Parties agree as
               follows:

               (i)   Vendor agrees to vigorously pursue the recovery of damages
                     against the third party causing the damage, including
                     through negotiations, dispute resolution, or both, to
                     maximize the damages recoverable against such third party;

               (ii)  Vendor agrees to pass through to Customer any amounts that
                     Vendor actually recovers from such third party relating to
                     damages incurred in connection with Services provided to
                     Customer under this Schedule;

               (iii) Customer agrees that in the event that Vendor has paid any
                     amounts to Customer pursuant to Subsection (a) of this
                     Section prior to the recovery of damages from a third
                     party, Vendor may reduce the amount of recovery received
                     from such third party by the amount previously paid to
                     Customer in respect of such event causing the damages; and

               (iv)  Amounts recovered by Vendor from third parties shall be
                     first passed on to Customer until Customer's full damages
                     are satisfied.

          (c)  IN NO EVENT, WHETHER IN CONTRACT OR IN TORT (INCLUDING BREACH OF
               WARRANTY, NEGLIGENCE AND STRICT LIABILITY IN TORT), SHALL A PARTY
               BE LIABLE TO THE OTHER PARTY FOR INDIRECT OR CONSEQUENTIAL,
               EXEMPLARY, PUNITIVE OR SPECIAL DAMAGES EVEN IF SUCH PARTY HAS
               BEEN ADVISED OF THE POSSIBILITY OF SUCH DAMAGES IN ADVANCE.

          (d)  The limitations set forth in Subsection (a) of this Section shall
               not apply with respect to (i) intentional breach by Vendor; (ii)
               damages occasioned by an intentional tort or the gross negligence
               of Vendor; (iii) damages occasioned by Vendor' breach of its
               obligations described in Article 11 (Confidentiality) of the
               Master Agreement, or (iv) claims subject to indemnification
               pursuant to this Agreement (such amounts paid by the indemnitee
               to third parties shall be deemed to be direct damages) other than
               claims subject to the indemnity set forth in Section 15(a) of the
               Master Agreement.

--------------------------------------------------------------------------------
Network Services Agreement     America Online, Inc./BBN Corporation CONFIDENTIAL
Schedule C                    Schedule C - Page 29
<PAGE>

                       CONFIDENTIAL TREATMENT REQUESTED

          (e)  Each Party shall have a duty to reasonably mitigate (i.e.,
               minimize) damages for which the other Party is responsible.

--------------------------------------------------------------------------------
Network Services Agreement     America Online, Inc./BBN Corporation CONFIDENTIAL
Schedule C                    Schedule C - Page 30
<PAGE>

                       CONFIDENTIAL TREATMENT REQUESTED

                                   EXHIBIT C-1

                    Broadband Backhaul Purchase Commitment

1.   Confidentiality

     This Exhibit specifies Customer's Broadband Backhaul Purchase Commitments
     pursuant to Schedule C. The Parties specifically acknowledge that the
     purchase commitment information contained herein is highly confidential and
     that its disclosure to the public or third parties could cause significant
     harm to either Customer or Vendor or both.

2.   Broadband backhaul purchase commitments

     2.1. DSL Purchase Commitment.

          Customer agrees to order Broadband Backhaul Services such that:

          (a)  Commencing upon the Effective Date through [*Material Omitted and
               Separately Filed Under an Application for Confidential
               Treatment], no less than [*Material Omitted and Separately Filed
               Under an Application for Confidential Treatment] of the
               [*Material Omitted and Separately Filed Under an Application for
               Confidential Treatment] are [*Material Omitted and Separately
               Filed Under an Application for Confidential Treatment]; and

          (b)  Commencing upon [*Material Omitted and Separately Filed Under an
               Application for Confidential Treatment] through no less than
               [*Material Omitted and Separately Filed Under an Application for
               Confidential Treatment] of the [*Material Omitted and Separately
               Filed Under an Application for Confidential Treatment] are
               [*Material Omitted and Separately Filed Under an Application for
               Confidential Treatment].

     (such commitment, as may be reduced pursuant to the Agreement, the "DSL
     Purchase Commitment").

     2.2. Other Broadband Purchase Commitments.
          ------------------------------------

          Customer agrees to order Broadband Backhaul Services such that, during
          the [*Material Omitted and Separately Filed Under an Application for
          Confidential Treatment], no less than [*Material Omitted and
          Separately Filed Under an Application for Confidential Treatment] of
          the [*Material Omitted and Separately Filed Under an Application for
          Confidential Treatment] are [*Material Omitted and Separately Filed
          Under an Application for Confidential Treatment] such commitment as
          may be reduced pursuant to the [*Material Omitted and Separately Filed
          Under an Application for Confidential Treatment].

     2.3. Provision of Subscriber Line Information.
          ----------------------------------------

          Customer will provide Vendor with information regarding the number of
          Vendor [*Material Omitted and Separately Filed Under an Application
          for Confidential Treatment] relative to the [*Material Omitted and
          Separately Filed Under an Application for Confidential Treatment] and
          [*Material Omitted and Separately Filed Under an Application for
          Confidential Treatment] during each [*Material Omitted and Separately
          Filed Under an Application for Confidential Treatment] of each
          [*Material Omitted and Separately Filed Under an Application for
          Confidential Treatment] of the [*Material Omitted and Separately Filed
          Under an Application for Confidential Treatment].

3.   Reduction in Broadband Purchase Commitments for Delivery Failure

     3.1. Reduction Calculation.
          ---------------------

--------------------------------------------------------------------------------
Network Services Agreement     America Online, Inc./BBN Corporation CONFIDENTIAL
Exhibit C-1 to Schedule C      Exhibit C-1 Page 1
<PAGE>

                       CONFIDENTIAL TREATMENT REQUESTED

          Reduction of the Broadband Backhaul Purchase Commitments pursuant to
          Section 3.2(b)(ii) of Schedule C shall be determined in accordance
          with this Section. As of the [*Material Omitted and Separately Filed
          Under an Application for Confidential Treatment] of each [*Material
          Omitted and Separately Filed Under an Application for Confidential
          Treatment], beginning on [*Material Omitted and Separately Filed Under
          an Application for Confidential Treatment]. the Parties will calculate
          [*Material Omitted and Separately Filed Under an Application for
          Confidential Treatment]from and after [*Material Omitted and
          Separately Filed Under an Application for Confidential Treatment] will
          equal the [*Material Omitted and Separately Filed Under an Application
          for Confidential Treatment] (1) [*Material Omitted and Separately
          Filed Under an Application for Confidential Treatment] as adjusted, as
          of the prior [*Material Omitted and Separately Filed Under an
          Application for Confidential Treatment] (2) either if (A) [*Material
          Omitted and Separately Filed Under an Application for Confidential
          Treatment] is on or before [*Material Omitted and Separately Filed
          Under an Application for Confidential Treatment] as measured at such
          [*Material Omitted and Separately Filed Under an Application for
          Confidential Treatment] (B) [*Material Omitted and Separately Filed
          Under an Application for Confidential Treatment] is on or after
          [*Material Omitted and Separately Filed Under an Application for
          Confidential Treatment] as measured at such [*Material Omitted and
          Separately Filed Under an Application for Confidential Treatment].

     3.2. Example of Reduction Calculation.
          --------------------------------

          This Section 3.2 sets forth examples, referenced in Section
          3.2(b)(iii) of Schedule C, of reductions in the Broadband Backhaul
          Purchase Commitments for delivery failures pursuant to Section 3.2(b)
          of Schedule C.

          (a)  As of [*Material Omitted and Separately Filed Under an
               Application for Confidential Treatment] within the [*Material
               Omitted and Separately Filed Under an Application for
               Confidential Treatment] have not yet been [*Material Omitted and
               Separately Filed Under an Application for Confidential
               Treatment]:

               (i)   [*Material Omitted and Separately Filed Under an
                     Application for Confidential Treatment];

               (ii)  [*Material Omitted and Separately Filed Under an
                     Application for Confidential Treatment];

               (iii) [*Material Omitted and Separately Filed Under an
                     Application for Confidential Treatment];

               (iv)  [*Material Omitted and Separately Filed Under an
                     Application for Confidential Treatment] as of that
                     [*Material Omitted and Separately Filed Under an
                     Application for Confidential Treatment] equals the
                     [*Material Omitted and Separately Filed Under an
                     Application for Confidential Treatment].

          (b)  As of [*Material Omitted and Separately Filed Under an
               Application for Confidential Treatment] in the applicable
               [*Material Omitted and Separately Filed Under an Application for
               Confidential Treatment] have not yet been [*Material Omitted and
               Separately Filed Under an Application for Confidential
               Treatment]:

               (i)   [*Material Omitted and Separately Filed Under an
                     Application for Confidential Treatment];

               (ii)  [*Material Omitted and Separately Filed Under an
                     Application for Confidential Treatment];

               (iii) [*Material Omitted and Separately Filed Under an
                     Application for Confidential Treatment];

               (iv)  [*Material Omitted and Separately Filed Under an
                     Application for Confidential Treatment] as of that
                     [*Material Omitted and Separately Filed Under an
                     Application for Confidential Treatment] equals the
                     [*Material Omitted and Separately Filed Under an
                     Application for Confidential Treatment].

--------------------------------------------------------------------------------
Network Services Agreement     America Online, Inc./BBN Corporation CONFIDENTIAL
Exhibit C-1 to Schedule C      Exhibit C-1 - Page 2
<PAGE>

                       CONFIDENTIAL TREATMENT REQUESTED

          (c)  As of [*Material Omitted and Separately Filed Under an
               Application for Confidential Treatment] in the applicable
               [*Material Omitted and Separately Filed Under an Application for
               Confidential Treatment] have not yet been [*Material Omitted and
               Separately Filed Under an Application for Confidential
               Treatment]:

               (i)   [*Material Omitted and Separately Filed Under an
                     Application for Confidential Treatment];

               (ii)  [*Material Omitted and Separately Filed Under an
                     Application for Confidential Treatment];

               (iii) [*Material Omitted and Separately Filed Under an
                     Application for Confidential Treatment];

               (iv)  [*Material Omitted and Separately Filed Under an
                     Application for Confidential Treatment] as of that
                     [*Material Omitted and Separately Filed Under an
                     Application for Confidential Treatment] equals the
                     [*Material Omitted and Separately Filed Under an
                     Application for Confidential Treatment];

          (d)  As of[*Material Omitted and Separately Filed Under an Application
               for Confidential Treatment] in the applicable [*Material Omitted
               and Separately Filed Under an Application for Confidential
               Treatment] have not yet been [*Material Omitted and Separately
               Filed Under an Application for Confidential Treatment]:

               (i)   [*Material Omitted and Separately Filed Under an
                     Application for Confidential Treatment];

               (ii)  [*Material Omitted and Separately Filed Under an
                     Application for Confidential Treatment];

               (iii) [*Material Omitted and Separately Filed Under an
                     Application for Confidential Treatment];

               (iv)  [*Material Omitted and Separately Filed Under an
                     Application for Confidential Treatment] as of that
                     [*Material Omitted and Separately Filed Under an
                     Application for Confidential Treatment] equals the
                     [*Material Omitted and Separately Filed Under an
                     Application for Confidential Treatment].

--------------------------------------------------------------------------------
Network Services Agreement     America Online, Inc./BBN Corporation CONFIDENTIAL
Exhibit C-1 to Schedule C      Exhibit C-1 - Page 3
<PAGE>

                       CONFIDENTIAL TREATMENT REQUESTED

                                   EXHIBIT C-2

                  Prices for Broadband Backhaul Access Services

1.   Confidentiality

     This Exhibit C-2 specifies the prices for Broadband Backhaul Services
     provided pursuant to the Master Agreement and Schedule C. The Parties
     specifically acknowledge that the pricing information contained herein is
     highly confidential and that its disclosure to the public or third parties
     could cause significant harm to either Customer or Vendor or both.

2.   PRICES FOR BROADBAND BACKHAUL SERVICES

     2.1. Monthly Per Subscriber Line Charge.
          ----------------------------------

          "Monthly Per Subscriber Line Charge" shall be defined as follows:

          (a)  If a Vendor Broadband Subscriber Line is a Covered Subscriber
               Line, and

               (i)   the Monthly Subscriber Line Aggregate is equal to or
                     greater than [*Material Omitted and Separately Filed Under
                     an Application for Confidential Treatment] but less than
                     [*Material Omitted and Separately Filed Under an
                     Application for Confidential Treatment] then the Monthly
                     Subscriber Per Line Charge shall be [*Material Omitted and
                     Separately Filed Under an Application for Confidential
                     Treatment];

               (ii)  the Monthly Subscriber Line Aggregate is greater than or
                     equal [*Material Omitted and Separately Filed Under an
                     Application for Confidential Treatment] but less than
                     [*Material Omitted and Separately Filed Under an
                     Application for Confidential Treatment] then the Monthly
                     Subscriber Per Line Charge shall be [*Material Omitted and
                     Separately Filed Under an Application for Confidential
                     Treatment];

               (iii) the Monthly Subscriber Line Aggregate is greater than or
                     equal to [*Material Omitted and Separately Filed Under an
                     Application for Confidential Treatment] but less than
                     [*Material Omitted and Separately Filed Under an
                     Application for Confidential Treatment] then the Monthly
                     Subscriber Per Line Charge shall be [*Material Omitted and
                     Separately Filed Under an Application for Confidential
                     Treatment];

               (iv)  the Monthly Subscriber Line Aggregate is greater than or
                     equal [*Material Omitted and Separately Filed Under an
                     Application for Confidential Treatment] but less than
                     [*Material Omitted and Separately Filed Under an
                     Application for Confidential Treatment] then the Monthly
                     Subscriber Per Line Charge shall be [*Material Omitted and
                     Separately Filed Under an Application for Confidential
                     Treatment];

--------------------------------------------------------------------------------
Network Services Agreement     America Online, Inc./BBN Corporation CONFIDENTIAL
Exhibit C-2                     Exhibit C-2 - Page 1
<PAGE>

                       CONFIDENTIAL TREATMENT REQUESTED

               (v)  the Monthly Subscriber Line Aggregate is greater than or
                    equal to [*Material Omitted and Separately Filed Under an
                    Application for Confidential Treatment] but less than
                    [*Material Omitted and Separately Filed Under an Application
                    for Confidential Treatment] then the Monthly Per Subscriber
                    Line Charge shall be [*Material Omitted and Separately Filed
                    Under an Application for Confidential Treatment].

               (vi) the Monthly Subscriber Line Aggregate is greater than
                    [*Material Omitted and Separately Filed Under an Application
                    for Confidential Treatment]. then the Monthly Per Subscriber
                    Line Charge shall be [*Material Omitted and Separately Filed
                    Under an Application for Confidential Treatment].

          (b)  If a Vendor Broadband Subscriber Line is not a Covered Subscriber
               Line, and

               (i)   the Monthly Subscriber Line Aggregate is equal to or
                     greater than [*Material Omitted and Separately Filed Under
                     an Application for Confidential Treatment] but less than
                     [*Material Omitted and Separately Filed Under an
                     Application for Confidential Treatment] then the Monthly
                     Per Subscriber Line Charge shall be [*Material Omitted and
                     Separately Filed Under an Application for Confidential
                     Treatment].

               (ii)  the Monthly Subscriber Line Aggregate is greater than or
                     equal to [*Material Omitted and Separately Filed Under an
                     Application for Confidential Treatment] but less than
                     [*Material Omitted and Separately Filed Under an
                     Application for Confidential Treatment] then the Monthly
                     Per Subscriber Line Charge shall be [*Material Omitted and
                     Separately Filed Under an Application for Confidential
                     Treatment];

               (iii) the Monthly Subscriber Line Aggregate is greater than or
                     equal [*Material Omitted and Separately Filed Under an
                     Application for Confidential Treatment] but less than
                     [*Material Omitted and Separately Filed Under an
                     Application for Confidential Treatment] then the Monthly
                     Per Subscriber Line Charge shall be [*Material Omitted and
                     Separately Filed Under an Application for Confidential
                     Treatment];

               (iv)  the Monthly Subscriber Line Aggregate is greater than or
                     equal to [*Material Omitted and Separately Filed Under an
                     Application for Confidential Treatment] but less than
                     [*Material Omitted and Separately Filed Under an
                     Application for Confidential Treatment] then the Monthly
                     Per Subscriber Line Charge shall be [*Material Omitted and
                     Separately Filed Under an Application for Confidential
                     Treatment].

               (v)   the Monthly Subscriber Line Aggregate is greater than or
                     equal [*Material Omitted and Separately Filed Under an
                     Application for Confidential Treatment] but less than
                     [*Material Omitted and Separately Filed Under an
                     Application for Confidential Treatment] then the Monthly
                     Per Subscriber Line Charge shall be [*Material Omitted and
                     Separately Filed Under an Application for Confidential
                     Treatment].

--------------------------------------------------------------------------------
Network Services Agreement     America Online, Inc./BBN Corporation CONFIDENTIAL
Exhibit C-2                    Exhibit C-2 - Page 2
<PAGE>

                       CONFIDENTIAL TREATMENT REQUESTED

               (vi) the Monthly Subscriber Line Aggregate is greater than
                    [*Material Omitted and Separately Filed Under an Application
                    for Confidential Treatment] then the Monthly Per Subscriber
                    Line Charge shall be [*Material Omitted and Separately Filed
                    Under an Application for Confidential Treatment].

          Notwithstanding the foregoing, each of the foregoing Monthly Per
          Subscriber Line Charges may be [*Material Omitted and Separately Filed
          Under an Application for Confidential Treatment] pursuant to Section
          [*Material Omitted and Separately Filed Under an Application for
          Confidential Treatment]. As used herein, [*Material Omitted and
          Separately Filed Under an Application for Confidential
          Treatment] means a [*Material Omitted and Separately Filed Under an
          Application for Confidential Treatment] that is provided by (A)
          [*Material Omitted and Separately Filed Under an Application for
          Confidential Treatment], (B) [*Material Omitted and Separately Filed
          Under an Application for Confidential Treatment], (C) [*Material
          Omitted and Separately Filed Under an Application for Confidential
          Treatment] (D) [*Material Omitted and Separately Filed Under an
          Application for Confidential Treatment] of any such [*Material Omitted
          and Separately Filed Under an Application for Confidential Treatment].

     2.2. Proration of Monthly Per Subscriber Line Charge.
          -----------------------------------------------

          If Customer is able to provide Vendor with information [*Material
          Omitted and Separately Filed Under an Application for Confidential
          Treatment] then Vendor shall [*Material Omitted and Separately Filed
          Under an Application for Confidential Treatment] of the applicable
          Monthly Per Subscriber Line Charge with respect to such [*Material
          Omitted and Separately Filed Under an Application for Confidential
          Treatment] The applicable Monthly Per Subscriber Line Charge with
          respect to [*Material Omitted and Separately Filed Under an
          Application for Confidential Treatment] If Customer is not able to
          provide Vendor with such information, then

          (a)  no later than [*Material Omitted and Separately Filed Under an
               Application for Confidential Treatment] days after the end of
               each calendar month, Customer will provide Vendor [*Material
               Omitted and Separately Filed Under an Application for
               Confidential Treatment] the Monthly Per Subscriber Line Charge.
               [*Material Omitted and Separately Filed Under an Application for
               Confidential Treatment] and

          (b)  for each [*Material Omitted and Separately Filed Under an
               Application for Confidential Treatment], Customer shall pay the
               applicable Monthly Per Subscriber Line Charge; provided, however,
               that for [*Material Omitted and Separately Filed Under an
               Application for Confidential Treatment] of the applicable Monthly
               Per Subscriber Line Charge,

     2.3. Monthly Aggregate Subscriber Line Charge.
          ----------------------------------------

          (a)  "Monthly Aggregate Subscriber Line Charge" for a calendar month
               shall mean the greater of:

               (i)  [*Material Omitted and Separately Filed Under an Application
                    for Confidential Treatment] of the applicable Monthly Per
                    Subscriber Line Charge [*Material Omitted and Separately
                    Filed Under an Application for Confidential Treatment] and

               (ii) [*Material Omitted and Separately Filed Under an Application
                    for Confidential Treatment] (A) [*Material Omitted and
                    Separately Filed Under an Application for Confidential
                    Treatment] Monthly Per Subscriber Line Charge set forth in
                    Section [*Material Omitted and Separately Filed Under an
                    Application for Confidential Treatment] (B) [*Material
                    Omitted and Separately Filed Under an Application for
                    Confidential Treatment].

--------------------------------------------------------------------------------
Network Services Agreement     America Online, Inc./BBN Corporation CONFIDENTIAL
Exhibit C-2                    Exhibit C-2 - Page 3
<PAGE>

                       CONFIDENTIAL TREATMENT REQUESTED

          For example, if (A) [*Material Omitted and Separately Filed Under an
          Application for Confidential Treatment] (B) [*Material Omitted and
          Separately Filed Under an Application for Confidential Treatment]:

               (iii) [*Material Omitted and Separately Filed Under an
                     Application for Confidential Treatment].

               (iv)  [*Material Omitted and Separately Filed Under an
                     Application for Confidential Treatment].

               Accordingly, the Monthly Per Subscriber Line Charge [*Material
               Omitted and Separately Filed Under an Application for
               Confidential Treatment].

          (b)  Except with respect to the [*Material Omitted and Separately
               Filed Under an Application for Confidential Treatment]:

               (i)   [*Material Omitted and Separately Filed Under an
                     Application for Confidential Treatment];

               (ii)  [*Material Omitted and Separately Filed Under an
                     Application for Confidential Treatment];

               (iii) [*Material Omitted and Separately Filed Under an
                     Application for Confidential Treatment];

               (iv)  [*Material Omitted and Separately Filed Under an
                     Application for Confidential Treatment].

          (c)  Notwithstanding the foregoing, Vendor will [*Material Omitted and
               Separately Filed Under an Application for Confidential Treatment]
               the Monthly Per Subscriber Line Charge applicable to [*Material
               Omitted and Separately Filed Under an Application for
               Confidential Treatment] Monthly Per Subscriber Line Charge
               [*Material Omitted and Separately Filed Under an Application for
               Confidential Treatment].

--------------------------------------------------------------------------------
Network Services Agreement     America Online, Inc./BBN Corporation CONFIDENTIAL
Exhibit C-2                    Exhibit C-2 - Page 4
<PAGE>

                       CONFIDENTIAL TREATMENT REQUESTED

                                  SCHEDULE D

                                Other Services

During the Term, Customer will order from Vendor services (excluding Dial-Up
Access Services, Broadband Backhaul Services and Dial-Up Access Services
provided outside of the United States) (such services to be ordered the "Other
Services") such that the aggregate charges paid to Vendor and Vendor's
Affiliates for such Other Services are equal to or greater than [*Material
Omitted and Separately Filed Under an Application for Confidential
Treatment].dollars ($[*Material Omitted and Separately Filed Under an
Application for Confidential Treatment].) (such commitment the "Other Services
Purchase Commitment"); provided, however, that charges payable for such Other
Services ordered or purchased by Customer or a Special Affiliate of Customer
during December 1999 (collectively, the "Pre-Term Private Line Agreements")
shall contribute toward Customer's satisfaction of the Other Services Purchase
Commitment. Any orders or purchases of Other Services shall be subject to terms
and conditions mutually agreed upon by the Parties, which may include terms and
conditions similar to those set forth in the Master Agreement. Any agreement for
Vendor to provide Other Services to Customer that are private line services
(such services collectively the "Private Line Services") shall contain a
most-favored customer provision substantially similar to the one set forth in
Section 8.3(b) of Schedule B. In the event that (i) Customer is offered by a
third party services similar to the Private Line Services at prices and terms
more competitive that those offered by Vendor or Vendor's Affiliates to
Customer, (ii) Customer, in its sole discretion, requests Vendor to provide
Private Line Services at prices and terms at least as favorable to Customer as
such prices and terms offered by such third party, and (iii) Vendor or Vendor's
Affiliates declines to provide Private Line Services at such prices and terms,
then the Other Services Purchase Commitment shall be reduced by the aggregate
charges paid to such third party for such services.

--------------------------------------------------------------------------------
Network Services Agreement     America Online, Inc./BBN Corporation CONFIDENTIAL
Schedule D                     Schedule D - Page 1<PAGE>

                                                                    EXHIBIT 10.9

                       AGREEMENT FOR TRANSITION SERVICES

This Agreement for Transition Services is made between GTE Service Corporation,
a New York corporation, with offices at 1255 Corporate Drive, Irving, Texas
75038 and its affiliates (individually and collectively "GTE") on one hand, each
only with respect to the Services (defined below) it provides, and Genuity
Solutions Inc., a Delaware corporation, with offices at 3 Van de Graaff Drive,
Burlington, Massachusetts 01803 ("GENUITY"), and its subsidiaries and successors
in interest, on the other hand.

Whereas, GENUITY desires to obtain certain administrative services including
accounting and cash processing, billing, real estate management, and human
resources services on a transitional basis; and

Whereas, GTE desires to provide such services to GENUITY.

Now therefore, in consideration of the mutual terms and conditions of this
Agreement, the parties agree as follows:

1.   GENERAL.

     (a)  Services. GENUITY desires to obtain certain administrative
          --------
          transitional services on a non-exclusive basis from GTE or an
          affiliate company of GTE under the terms and conditions of this
          agreement and statements of work ("Statements of Work") entered into
          by the parties (this agreement and all attached Statements of work are
          collectively referred to as the "Agreement"), and GTE or its affiliate
          shall provide to GENUITY such administrative transitional services
          (individually and collectively, "Services"). If there is any conflict
          or inconsistency between the terms and conditions of a Statement of
          Work and the terms and conditions of this Agreement (excluding for
          this purpose the Statements of Work), the terms and conditions of the
          Statement of Work shall control.

     (b)  Statements of Work - Generally. Each of the Statements of Work entered
          ------------------------------
          into by the parties shall: (i) refer expressly to this Agreement; (ii)
          designate the date as of which the provisions of the Statement of Work
          shall be effective and, if applicable, the term or period of time
          during which GTE shall perform Services, provide resources or
          otherwise discharge its obligations as specified in the Statement of
          Work if different from the term set out in this Agreement (excluding
          for this purpose the Statement of Work); (iii) describe the Services
          to be performed, Work Product (as defined herein) to be delivered,
          resources to be provided or obligations to be discharged by GTE
          pursuant to the Statement of Work; (iv) describe the obligations of
          GENUITY related to the Statement of Work, including

                                                                    Page 1 of 55
<PAGE>

          any facilities, equipment, personnel and tasks or other support to be
          provided or performed by GENUITY; (v) specify the payments to be made
          to GTE under the Statement of Work, or, if applicable, the basis on
          which such payments shall be computed; and (vi) specify any other
          terms and conditions appropriate to the Services to be performed and
          the obligations of the parties. In the event of conflict or
          inconsistency between the terms and conditions of a Statement of Work
          and the terms and conditions of this Agreement (excluding for this
          purpose the Statement of Work), the terms and conditions of the
          Statement of Work shall control.

     (c)  Milestones, Phases and Timing; Changes. Each of the Statements of Work
          --------------------------------------
          shall set out, if applicable, milestones and phases of the work. When
          phases are specified, GTE shall not be obligated to proceed with work
          on the next phase until GENUITY has provided written authorization to
          proceed. If GENUITY has not provided GTE with written authorization to
          proceed on a specific phase, and it is necessary to commence or
          complete such phase in order to meet any milestones specified in the
          Statement of Work, GTE shall not have any obligations with respect to
          such milestones and the Statement of Work shall be deemed to be
          modified accordingly. The Statement of Work may be modified by mutual
          written agreement, signed by both parties. No verbal changes to the
          Statement of Work are permitted.

     (d)  Performance. All Services shall be performed in accordance with the
          -----------
          terms and conditions of this Agreement and the requirements, order of
          performance and delivery dates specified in each Statement of Work.
          GTE shall devote such time, efforts and resources to the performance
          of Services as are necessary to accomplish the tasks specified in any
          Statement of Work. GTE may call upon the expertise and/or assistance
          of its affiliates, subcontractors or consultants in the performance of
          such Services, provided that GTE shall obtain the prior written
          consent of GENUITY in the event it desires to use outside
          subcontractors or consultants. If a Statement of Work specifies that
          some or all of the work will be done by a subcontractors or
          consultant, no additional approval shall be required.

     (e)  Third Party Software Licenses. GENUITY acknowledges that GTE and its
          -----------------------------
          affiliates may be required to use certain software licensed to GTE by
          third parties to provide Services pursuant to this Agreement. If any
          licensor of such third party software requires the payment of any
          consideration to permit GTE to use the vendor's software in order to
          perform its obligations under this Agreement, GTE shall provide
          GENUITY with thirty (30) days prior written notice of such additional
          consideration. GENUITY shall have the option to (i) procure its own
          license to such software at its own expense, or (ii) authorize GTE to
          incur such required

                                                                    Page 2 of 55
<PAGE>

          additional consideration on its behalf and at GENUITY'S expense. In
          the event that GENUITY does not agree to either (i) or (ii) above, GTE
          shall not be required to provide the Services for which such third
          party licenses are required. If the third party requires GENUITY to
          secure rights in such third party software to receive the Services or
          to use the result of such Services, GENUITY shall be responsible for
          securing such rights at its own cost and expense.

2.  COMPENSATION AND BILLING.

     (a)  Invoices. The charges for the Services shall be set out in the
          --------
          applicable Statement of Work. GTE shall invoice GENUITY for Services
          in accordance with the payment schedule set forth in the applicable
          Statement of Work. Each invoice shall reference this Agreement and the
          applicable Statement of Work. The invoices shall be itemized to show
          the details as to all billed items. Payments shall be made within
          thirty (30) days from the date each invoice is received by GENUITY.

     (b)  Sales, Use and Other Taxes. In addition to the charges for Services,
          --------------------------
          GENUITY shall pay GTE an amount equal to any sales, use, privilege,
          gross revenue, excise, or any other tax (except income and franchise
          taxes), as well as any assessments or duties with respect to the
          Services lawfully levied by a duly constituted governmental authority
          and for which GTE is required, by law, to collect from GENUITY. In
          addition each party shall be responsible for all real and personal
          property taxes imposed on software and equipment owned by the
          respective parties on January 1 of every year. If GENUITY determines
          that any Services are exempt from a tax, GENUITY must provide GTE a
          properly completed exemption certificate, for each jurisdiction for
          which GENUITY is claiming an exemption, before GTE will exclude the
          respective tax from amounts charged to GENUITY. GENUITY will not
          deduct any tax amount from remittances to GTE until a properly
          completed exemption certificate, for all jurisdictions for which
          GENUITY is claiming an exemption, has been provided to GTE.

     (c)  Expense Reimbursement. GENUITY shall reimburse GTE for reasonable
          ---------------------
          expenses for travel, meals and lodging incurred by GTE in the
          performance of its obligations under this Agreement. Any such charges
          shall be in compliance with GTE's employee expense policies. There
          shall be no mark-up of such expense charges. GTE shall maintain
          documentation of expenses incurred, and shall provide copies of
          invoices of $100 or more upon GENUITY's request. GTE shall bill
          GENUITY monthly for expenses as they accrue. The parties will specify
          any limitation on the reimbursement of expenses in the applicable
          Statement of Work. It is acknowledged and agreed that if GTE is
          reasonably

                                                                    Page 3 of 55
<PAGE>

          required to incur expenses beyond such limitation in order to provide
          the Services, then GTE is excused from performing such Services until
          said expense limitation is removed or changed as mutually agreed,
          provided that GTE promptly notifies GENUITY of the need to exceed the
          limitation.

     (d)  Records. GTE shall maintain complete and accurate records in a form
          -------
          consistent with generally accepted accounting practices, to
          substantiate GTE charges. GTE shall retain, and make available upon
          request, such records for a period of three (3) years from the date of
          invoice for Services. GENUITY and its authorized agents, subject to
          obligations of confidentiality as set forth in this Agreement, shall
          have access to such records upon prior written request during normal
          business hours during the term of this Agreement and during the
          respective periods in which GTE is required to maintain such records
          pursuant to this subsection. Access to the records shall be made at
          the location where such records are normally maintained.

3.   TERM.

     This Agreement is effective as of the date of closing of the initial public
     offering of Genuity Inc. shares of stock ("Effective Date") and shall
     expire the earlier of: (a) one (1) year after the Effective Date or (b)
     expiration or termination of all of the Statements of Work under this
     Agreement unless earlier terminated under Section 24(a), (b) or (c) of this
     Agreement. This Agreement may not be renewed. GTE shall use its best
     efforts to provide all items, services and personnel necessary to
     effectuate and ensure a smooth and timely transition for Genuity from
     dependence on Services under such SOW to standalone ability to perform such
     Services itself or in conjunction with third parties.  Both parties shall
     make appropriate resources available in connection with such transition,
     and any such steps taken by GTE shall be accomplished prior to the
     expiration of the term of this Agreement.

                                                                    Page 4 of 55
<PAGE>

4.   ACCEPTANCE.

     (a)  Acceptance. Each Statement of Work shall specify the criteria that GTE
          ----------
          must meet in order for the Work Products described in the Statement of
          Work to be accepted by GENUITY. It shall also specify a test plan, and
          such other information as GTE and GENUITY mutually deem appropriate
          and the period of time that GENUITY shall have to review such Work
          Product and provide notice of acceptance or rejection to GTE. Failure
          to accept or reject such Work Product within the specified period of
          time or the commercial use of such Work Product by or for the benefit
          of GENUITY shall be deemed to be acceptance.

     (b)  Rejection and Revision. If GENUITY rejects any Work Product, it shall
          ----------------------
          specify in reasonable detail in writing the reasons for rejection and
          the requirements for revision. If the notice of rejection is not
          sufficiently detailed to allow GTE to determine why such Work Product
          is unacceptable, GTE may request in writing that GENUITY provide
          sufficient additional information. If GTE and GENUITY have joint
          responsibility for the Work Product and the Work Product requires
          revision, GTE shall assist GENUITY in making revisions necessary for
          the Work Product to meet the acceptance criteria within a period of
          time that is reasonable under the circumstances. If GTE has sole
          responsibility for the Work Product, then it shall make the necessary
          revisions within a period of time that is reasonable under the
          circumstances.

5.   CONFIDENTIAL INFORMATION.

     (a)  Confidentiality. In the course of requesting and performing Services
          ---------------
          pursuant to this Agreement, each party may receive or acquire from the
          other information or data pertaining to specifications, drawings,
          sketches, models, samples, computer programs, methods, concepts, know-
          how, techniques, processes, and other technical or business
          information that the other party desires to protect against
          unauthorized use or further disclosure. Unless otherwise expressly set
          forth in a Statement of Work, for purposes of this Agreement,
          "Confidential Information" shall mean: (i) any information in written,
          other tangible or electronic form which is labeled by the disclosing
          party as "confidential", "proprietary" or with a legend of similar
          import; (ii) software in any form (including related documentation),
          whether or not labeled in accordance with the preceding; (iii)
          Services and Work Products provided pursuant to this Agreement, with
          the ownership of and proprietary interest therein being defined in the
          applicable Statement of Work; or (iv) information orally disclosed and
          identified as confidential at the time of such disclosure which is
          summarized in writing within thirty (30) days of such disclosure. Each
          party shall remain the exclusive owner of its Confidential
          Information.

                                                                    page 5 of 55
<PAGE>

     (b)  Use of Confidential Information. The Confidential Information of the
          -------------------------------
          disclosing party may be used by the receiving party only for the
          performance or use of Services or Work Products to be provided
          pursuant to this Agreement and may only be disclosed to those
          employees, subcontractors or agents of the receiving party who have a
          need to know in order to perform or use Services or Work Products
          pursuant to this Agreement. Except and to the extent set forth in
          Section 5(c), the receiving party may not disclose Confidential
          Information of the other party to any other person, entity, or the
          public without the prior written consent of the disclosing party.
          However, such Confidential Information may be disclosed by the
          receiving party without the necessity of prior written consent, to the
          receiving party's subcontractors or consultants who require access to
          such Confidential Information to perform or use the Services under
          this Agreement, provided such persons have entered into written
          agreements which contain obligations of nondisclosure and nonuse no
          less restrictive than set forth in this Section. It is agreed that
          such written agreements shall be enforceable by the disclosing party.

     (c)  Exceptions.  The obligations in Section 5(b) shall not apply to that
          ----------
          portion of any information received from the disclosing party which
          is: lawfully in the receiving party's possession, with no restriction
          on use or disclosure, prior to its acquisition from the disclosing
          party; received in good faith by the receiving party, with no
          restrictions on use or disclosure, from a third party not subject to
          any confidential obligation to the disclosing party; now or later
          becomes publicly known through no breach of confidential obligation by
          the receiving party; released by the disclosing party to any other
          person, firm or entity (including governmental agencies or bureaus)
          without restriction on use or disclosure; or independently developed
          by or for the receiving party without any reliance on or use of
          Confidential Information of the disclosing party.

     (d)  Disclosure and Notification. If a receiving party receives a request
          ---------------------------
          to disclose any Confidential Information of the disclosing party
          (whether pursuant to a subpoena, an order issued by a court or other
          governmental authority of competent jurisdiction or otherwise) and, on
          advice of legal counsel, determines that disclosure is required under
          applicable law, the receiving party agrees that, prior to disclosing
          any Confidential Information of the disclosing party, it shall (i)
          notify the disclosing party of the existence and terms of such request
          or advice, (ii) cooperate with the disclosing party in taking legally
          available steps to resist or narrow any such request or to otherwise
          eliminate the need for such disclosure at the disclosing party's sole
          expense, if requested to do so by the disclosing party, and (iii) if
          disclosure is required, it shall be the obligation of the disclosing
          party to use its commercially reasonable efforts to obtain a
          protective order or other reliable assurance that confidential
          treatment

                                                                    Page 6 of 55
<PAGE>

          shall be afforded to such portion of the Confidential Information of
          the disclosing party as is required to be disclosed.

     (e)  Continuing Obligation. The obligation of non-disclosure and non-use
          ---------------------
          with respect to Confidential Information of the disclosing party shall
          survive termination of this Agreement and shall continue for a period
          of 5 years thereafter, provided that the obligations of non-disclosure
          and non-use shall continue in perpetuity for software included in
          Confidential Information.

6.   OWNERSHIP AND LICENSE OF WORK PRODUCTS.

     (a)  Ownership. Unless expressly provided otherwise in the applicable
          ---------
          Statement of Work, the ownership of any and all right, title and
          interest in and to work products (including without limitation:
          computer programs and documentation; photographs; logos; drawings;
          artistic and graphical works; reports; data; information; and other
          works of authorship) made by Service Provider, or its suppliers or
          contractors, during performance of Services for Service Recipient in
          accordance with the applicable Statement of Work (all such works
          herein "Work Products"), shall be determined in accordance with the
          terms and conditions of the Software Development and Technical
          Services Agreement relating to ownership of intellectual property,
          with those terms and conditions being applied to any Statement of Work
          issued hereunder and being incorporated herein in their entirety by
          this reference.

     (b)  License. Unless expressly provided otherwise in the applicable
          -------
          Statement of Work:

          (1)  If Service Provider owns any Work Products, any license granted
               to Service Recipient by Service Provider in or to any such Work
               Products shall be on the same terms and conditions as the license
               grant by GTE to GENUITY contained in the Software License
               Agreement, with such terms and conditions being incorporated
               herein in their entirety by this reference.

          (2)  If Service Recipient owns any Work Products, and subject to
               Service Provider's obligations with respect to Service
               Recipient's Confidential Information, Service Provider shall
               retain a non-exclusive, perpetual, world-wide, royalty-free
               license to use any such Work Product for its ordinary and usual
               business purposes.

                                                                    Page 7 of 55
<PAGE>

7.   DISPUTE RESOLUTION.

     (a)  General. Except as provided in subparagraph 7(d) below, any
          -------
          controversy or claim arising out of or relating to this Agreement, or
          the breach thereof, shall attempt to be settled first, by good faith
          efforts of the parties to reach mutual agreement, and second, if
          mutual agreement is not reached to resolve the dispute, by final,
          binding arbitration as set out in paragraph 6(c) below.

     (b)  Initial Resolution. A party that wishes to initiate the dispute
          ------------------
          resolution process shall send written notice to the other party with a
          summary of the controversy and a request to initiate these dispute
          resolution procedures. Each party shall appoint a knowledgeable,
          responsible representative from the company who has the authority to
          settle the dispute, to meet and negotiate in good faith to resolve the
          dispute. The discussions shall be left to the discretion of the
          representatives, who may utilize other alternative dispute resolution
          procedures such as mediation to assist in the negotiations.
          Discussions and correspondence among the representatives for purposes
          of these negotiations shall be treated as Confidential Information
          developed for purposes of settlement, shall be exempt from discovery
          and production, and shall not be admissible in the arbitration
          described above or in any lawsuit pursuant to Rule 408 of the Federal
          Rules of Evidence. Documents identified in or provided with such
          communications, which are not prepared for purposes of the
          negotiations, are not so exempted and may, if otherwise admissible, be
          admitted in evidence in the arbitration or lawsuit. The parties agree
          to pursue resolution under this subsection for a minimum of 60 days
          before requesting arbitration.

     (c)  Arbitration. If the dispute is not resolved under the preceding
          -----------
          subsection within 60 days of the initial written notice, either party
          may demand arbitration by sending written notice to the other party.
          The parties shall promptly submit the dispute to the American
          Arbitration Association for resolution by a single neutral arbitrator
          acceptable to both parties, as selected under the rules of the
          American Arbitration Association. The dispute shall then be
          administered according to the American Arbitration Association's
          Commercial Arbitration Rules, with the following modifications: (i)
          the arbitration shall be held in a location mutually acceptable to the
          parties, and if the parties do not agree, the location shall be New
          York City; (ii) the arbitrator shall be licensed to practice law;
          (iii) the arbitrator shall conduct the arbitration as if it were a
          bench trial and shall use, apply and enforce the Federal Rules of
          Evidence and Federal Rules of Civil Procedure; (iv) except for
          breaches related to Confidential Information the arbitrator shall have
          no power or authority to make any award that provides for
          consequential, punitive or exemplary damages; (v)

                                                                    Page 8 of 55
<PAGE>

          the arbitrator shall control the scheduling so that the hearing is
          completed no later than 60 days after the date of the demand for
          arbitration; and (vi) the arbitrator's decision shall be given within
          5 days thereafter in summary form that states the award, without
          written decision, which shall follow the plain meaning of this
          Agreement, the relevant documents, and the intent of the parties.
          Judgment on the award rendered by the arbitrator may be entered in any
          court having jurisdiction over the parties. Each party to the dispute
          shall bear its own expenses arising out of the arbitration, except
          that the expenses of the facilities to conduct the arbitration and the
          fees of the arbitrator shall be shared equally by the parties.

     (d)  Injunctive Relief. The foregoing notwithstanding, each party shall
          -----------------
          have the right to seek injunctive relief in an applicable court of law
          or equity independent of any resolution of the dispute in accordance
          with the foregoing.

8.   RELATIONSHIP OF PARTIES.

     (a)  Independent Contractors. In providing any Services pursuant to this
          -----------------------
          Agreement, GTE and its affiliates are independent contractors and not
          agents or representatives of GENUITY. Persons furnished by the
          respective parties shall be solely the employees or agents of such
          parties, respectively, and shall be under the sole and exclusive
          direction and control of such parties. They shall not be considered
          employees of the other party or parties for any purpose. Each party
          shall also be responsible, respectively, for payment of taxes,
          including federal, state, and municipal taxes, chargeable or assessed
          with respect to its employees or agents, such as social security,
          unemployment, worker's compensation, disability insurance and federal
          and state income tax withholding.

     (b)  No Performance.  Neither party undertakes by this Agreement or any
          --------------
          Statement of Work to conduct the business or operations of the other
          party. Nothing contained in this Agreement or any Statement of Work is
          intended to give rise to a partnership or joint venture between the
          parties or to impose upon the parties any of the duties or
          responsibilities of partners or joint venturers.

9.   FORCE MAJEURE.

     If performance of any Services under this Agreement is prevented,
     restricted or interfered with by reason of acts of God, wars, revolution,
     civil commotion, acts of public enemy, embargo, acts of government in its
     sovereign capacity, labor difficulties, including without limitation,
     strikes, slowdowns, picketing or boycotts,

                                                                    Page 9 of 55
<PAGE>

     communication line failures, power failures, or any other circumstances
     beyond the reasonable control and not involving any fault or negligence of
     the party affected, the party affected, upon giving prompt notice to the
     other party, shall be excused from such performance on a day-to-day basis
     during the continuance of such prevention, restriction, or interference
     (and the other party shall likewise be excused on a day-to-day basis during
     the same period, from performance of its obligations which are dependent
     upon or affected by such nonperformance), provided, however, that the party
     so affected shall use its commercially reasonable efforts to avoid or
     remove such causes of nonperformance and both parties shall proceed
     immediately with the performance of their obligations under this Agreement
     whenever such causes are removed or cease.

     If a force majeure condition continues to prevent a party from performing
     for more than (30) consecutive days, then the other party may terminate the
     applicable Statement of Work.

10.  REGULATORY COMPLIANCE.

     (a)  Cooperation.  This Agreement is subject at all times to any statute,
          -----------
          order, rule, or regulation or any state or federal regulatory agency
          having competent jurisdiction over one or both of the parties hereto
          or the Services provided hereby.  The parties agree to cooperate with
          each other and with any applicable regulatory agency so that any and
          all necessary approvals may be obtained.  During the term of this
          Agreement, the parties agree to continue to cooperate with each other
          in any review of this Agreement by a regulatory agency so that the
          benefits of this Agreement may be achieved.

     (b)  Filing Agreement.  Notwithstanding the effective date and term of this
          ----------------
          Agreement as stated elsewhere, to the extent that any statute, order,
          rule or regulation or any regulatory agency having competent
          jurisdiction over one or both parties to this Agreement, shall require
          that this Agreement or subsequent amendment be filed with or approved
          by such regulatory agency before the Agreement or amendment may be
          effective, this Agreement or amendment shall not be effective in such
          jurisdiction until the first business day after such approval or
          filing shall have occurred.

11.  INDEMNIFICATION.

     (a)  General. GTE and GENUITY, to the fullest extent permitted by law, each
          -------
          shall defend, indemnify and hold harmless the other and its
          affiliates, officers, agents and employees from any and all amounts
          payable under any judgment, verdict, court order or settlement (and
          associated fees and disbursements of counsel) arising from or related
          to any third-party claims

                                                                   Page 10 of 55
<PAGE>

          for injury, sickness, disease or death of any person or damage to any
          real or tangible personal property or assets to the extent arising
          from the indemnitor's (either directly or through its officers,
          agents, subcontractors or representatives) negligence or willful
          misconduct in the performance of this Agreement provided, however,
          that if a claim is the result of the joint negligence or joint willful
          misconduct of GTE and GENUITY, the amount of the claim for which each
          party is entitled to indemnification shall be limited to that portion
          of such claim that is attributable to the negligence or willful
          misconduct of the indemnifying party. The parties agree that the price
          for Services provided under this Agreement includes consideration for
          the obligation to indemnify as set out in this Section.

     (b)  Losses. GENUITY and GTE each shall be responsible for any and all
          ------
          claims, actions, damages, liabilities, costs and expenses, including
          reasonable attorneys' fees and expenses (collectively, "Losses"), to
          their respective tangible personal or real property (whether owned or
          leased), and each party agrees to look only to its own insuring
          arrangements (if any) with respect to such Losses. Subject to the
          procedures set forth below, each party shall indemnify, defend, and
          hold the other party harmless from any and all Losses arising out of,
          under or in connection with claims for which the indemnitor is
          responsible under the preceding sentence.

     (c)  Waivers. GENUITY and GTE waive all rights to recover against each
          -------
          other for any Loss to their respective tangible personal property
          (whether owned or leased) from any cause covered by insurance
          maintained by each of them, including their respective deductibles or
          self-insured retentions. GENUITY and GTE shall cause their respective
          insurers to issue appropriate waivers of subrogation rights
          endorsements to all property insurance policies maintained by each
          Party. Each Party shall give the other written notice if a waiver of
          subrogation is unobtainable or obtainable only at additional expense.
          If the Party receiving such notice agrees to reimburse the other Party
          for such additional expense, the other Party shall obtain such waiver
          of subrogation. If a waiver is unobtainable or if a Party elects not
          to pay the additional expense of a waiver, then neither Party nor
          their insurers shall waive such subrogation rights.

     (d)  Defense. Except as otherwise set forth in the applicable Statement of
          -------
          Work, and subject to the limitations and procedures set forth below,
          GTE agrees to defend GENUITY against any action to the extent that
          such action is based upon a claim that the Service provided by GTE
          pursuant to this Agreement (i) infringes a United States copyright,
          (ii) infringes a United States patent or (iii) constitutes an unlawful
          disclosure, use or misappropriation of another party's trade secret
          and not as the result of any prohibited use or transfer by GENUITY.
          GTE shall bear the expense

                                                                   Page 11 of 55
<PAGE>

          of such defense and pay any Losses finally awarded by a court of
          competent jurisdiction that are directly attributable to such claim.

     (e)  Contributory Infringement. GTE shall not be liable to GENUITY for
          -------------------------
          claims of indirect or contributory infringement. Further, GTE shall
          have no liability to GENUITY hereunder if (i) the claim of
          infringement is based upon the use of Services or Work Products
          provided by GTE hereunder in connection or in combination with
          equipment, devices, data or software not supplied by GTE, and such
          infringement would not have occurred but for such use, (ii) such
          Services or Work Products are used outside of the scope of the rights
          and licenses granted to GENUITY; (iii) the Services or Work Products
          are modified by or for GENUITY (including by GTE at GENUITY's
          direction or instructions), and such infringement would not have
          occurred but for such modification; (iii) GENUITY uses any of the
          Services or Work Products in the practice of a patented process and
          there would be no infringement in the absence of such practice, or
          (iv) the claim of infringement arises out of the GTE's compliance with
          written directions provided by GENUITY and such infringement would not
          have occurred but for such compliance. For all of the foregoing
          exclusions, GENUITY shall defend and indemnify GTE for any
          infringement claims to the extent set forth in Section 11(d).

     (f)  Mitigation.  If a Service or Work Product becomes the subject of an
          ----------
          infringement claim, or in GTE's opinion is likely to become the
          subject of such a claim, then, in addition to defending the claim and
          paying any damages and attorneys' fees as required above, GTE may, at
          its option and in its sole discretion, and at its own cost and
          expense: (i) replace or modify such Service or Work Product to make it
          noninfringing or cure any claimed misuse of any third party trade
          secret; (ii) procure for GENUITY the right to continue using such
          Service or Work Product pursuant to this Agreement; or if neither (i)
          nor (ii) are possible at a commercially reasonable cost, (iii) require
          the return of such Service or Work Product, terminate the Statement of
          Work (to the extent it has not yet been completed) and terminate
          GENUITY's right to use the same and refund to GENUITY a pro-rata
          portion of the amount actually paid to GTE by GENUITY for such Service
          or Work Product. Notwithstanding the foregoing, if GTE exercises its
          right to require the return of such Service or Work Product and
          terminates GENUITY's right to use the same, to the extent permitted by
          applicable law, GENUITY may retain and continue to use such Service
          Work Product to the extent GENUITY agrees in writing to defend and
          indemnify GTE for any and all expenses, costs and liabilities
          associated with such continued possession and use of such Service or
          Work Product. The foregoing sets forth GTE's sole and exclusive
          obligations, and GENUITY's sole remedies, for infringement of
          intellectual property by Services or Work Product.

                                                                   Page 12 of 55
<PAGE>

     (g)  Conditions.  The indemnification obligations set forth in this Section
          ----------
          shall not apply unless the party claiming indemnification: (i)
          notifies the other promptly in writing of any matters in respect of
          which the indemnity may apply and of which the notifying party has
          knowledge, in order to allow the indemnitor the opportunity to
          investigate and defend the matter; provided, however, that the failure
          to so notify shall only relieve the indemnitor of its obligations
          under this Section if and to the extent that the indemnitor is
          prejudiced thereby; and (ii) gives the other party full control of the
          response thereto and the defense thereof, including any agreement
          relating to the settlement thereof. However, if the indemnitor fails
          to promptly assume the defense of the claim, the party entitled to
          indemnification may assume the defense at the indemnitor's cost and
          expense. The indemnitor shall not be responsible for any settlement or
          compromise made without its prior written consent, unless the
          indemnitee has tendered notice and the indemnitor has then refused to
          assume and defend the claim and it is later determined that the
          indemnitor was obligated to assume and defend the claim. The
          indemnitee agrees to cooperate in good faith with the indemnitor at
          the request and expense of the indemnitor.

12.  LIMITATION OF LIABILITY.

     (a)  General.  A party's and its affiliates' liability arising out of or
          -------
          relating to a Statement or Statements of Work and this Agreement,
          including without limitation on account of performance or
          nonperformance of obligations hereunder, regardless of the form of the
          cause of action, whether in contract, tort (including without
          limitation negligence), statute or otherwise, shall in no event exceed
          the lesser of (i) the price to be paid to GTE for the completed
          Statement of Work (whether set out as a fixed price, estimated price,
          not-to-exceed amount, or other similar expression of the total price
          for the work to be performed under the Statement of Work); or (ii) the
          amount actually paid by GENUITY to GTE for the particular Statement of
          Work from which the claim arises. The limitation in the immediately
          preceding sentence does not apply to a party's obligations under the
          Sections entitled Indemnification and Confidential Information, nor
          does it apply to willful misconduct or gross negligence on the part of
          a party.

     (b)  Limitation.  EXCEPT FOR BREACHES RELATED TO CONFIDENTIAL INFORMATION,
          ----------
          NEITHER PARTY SHALL BE LIABLE TO THE OTHER FOR ANY INDIRECT,
          INCIDENTAL, PUNITIVE, EXEMPLARY, SPECIAL OR CONSEQUENTIAL DAMAGE OR
          LOST PROFITS OF ANY KIND WHATSOEVER EVEN IF A PARTY OR ITS AFFILIATES
          HAVE BEEN APPRISED OF THE LIKELIHOOD OF SUCH DAMAGES OCCURRING.

                                                                   Page 13 of 55
<PAGE>

     (c)  Benefits Under Licenses.  Anything contained herein to the contrary
          -----------------------
          notwithstanding, this Agreement shall not constitute an agreement to
          start work, to provide Services or Work Product or to make available
          to GENUITY the benefits under any agreement, license or arrangement if
          doing so without the consent of and/or payment to another party
          thereto would constitute a breach thereof or in any material way
          affect the rights of GTE thereunder, unless and until such consent is
          obtained and payment, if any, made to such party by GTE, provided
          however, that GTE will use commercially reasonable efforts to secure
          such consents and benefits under any such agreement or arrangement. If
          GTE cannot: (i) obtain such consent; or (ii) GTE and the third party
          vendor cannot agree on a commercially reasonable payment, if such is
          required, or (iii) if providing the Services or Work Products or
          making the benefits under any such agreement, license or arrangement
          available would materially affect GTE's rights thereunder, GTE shall
          not be required to provide any Services or Work Products which are
          dependent upon such agreement, license or arrangement. GENUITY may,
          however, obtain the requisite license or rights, or pay such fees
          necessary for GTE to provide the Services.

13.  CHANGES IN MANNER OF PROVIDING SERVICES.

     GENUITY acknowledges that GTE and its affiliates may in the future
     determine to outsource certain information technology functions or perform
     such functions using different computer software operating systems or
     applications.  These changes may prevent GTE from providing certain
     Services or Work Products to GENUITY pursuant to this Agreement in the
     manner in which they have been provided prior to such change.  In the event
     GTE determines to take any such action, it will provide GENUITY with one
     hundred twenty (120) days prior written notice and will cooperate with
     GENUITY to enable GENUITY to continue to receive any affected Services and
     Work Products through arrangements with GTE's outsource providers or
     through conversion of GENUITY data for use on such operating systems or
     applications.  In the event GTE determines to make such changes, GENUITY
     shall have the right to terminate this Agreement or any affected STATEMENT
     OF WORK without any liability or penalty. Any customizations requested by
     GENUITY within or to the systems utilized by GTE to provide the Services
     shall be at GTE's discretion. GENUITY shall be required to pay the mutually
     agreed upon cost of such customizations.

14.  INSURANCE.

     (a)  Coverage.  GTE agrees to maintain in full force and effect during the
          --------
          term of this Agreement, and so long as the indemnity obligations
          hereunder are in effect, for GTE the following minimum insurance
          coverages: (i) Worker's Compensation and Occupational Disease covering
          GTE's full

                                                                   Page 14 of 55
<PAGE>

          liability under the Statutory Workers' Compensation Laws for the state
          in which the Service is being performed; (ii) Employer's Liability
          Insurance in the minimum amount of $100,000 per accident, $100,000
          disease per employee, and $500,000 disease aggregate; (iii) General
          Liability Insurance -Broad Form, including, but not limited to GTE's
          Protective Liability, Blanket Contractual Liability and Products
          Liability/Completed Operations in the minimum amounts of $1,000,000
          per occurrence; and (iv) If the use of motor vehicles is required,
          comprehensive Motor Vehicle Liability Insurance to include, but not
          limited to owned, non-owned, leased, and hired vehicles in the minimum
          amounts of $1,000,000 combined single limit per occurrence for
          Property Damage and any accident resulting in bodily injury or the
          death of one or more persons, and the consequential damages arising
          therefrom.

     (b)  Certificates of Insurance.  Certificates of Insurance, incorporating
          -------------------------
          the above-described endorsements, shall be furnished to GENUITY upon
          request.

15.  REPRESENTATIONS AND WARRANTIES.

     GTE represents, warrants, and covenants to GENUITY that:

     (a)  In performing Services, GTE shall comply with all applicable laws,
          codes, ordinances, orders, rules and regulations of local, state, and
          federal governments and agencies and instrumentalities, including, but
          not limited to, applicable wage and hour, safety and environmental
          laws, and all standards and regulations of appropriate regulatory
          commissions and similar agencies.

     (b)  All Services furnished by GTE shall be performed by qualified
          personnel at a level of professional performance standard within the
          industry in which the Services are provided.

     (c)  GTE has all rights and licenses to perform the Services contemplated
          by this Agreement and any Statement of Work incorporated herein.

     (d)  THE WARRANTIES IN THIS SECTION 15 AND ANY WARRANTY IN A STATEMENT OF
          WORK, BUT ONLY IF SPECIFICALLY IDENTIFIED AS AN EXPRESS WARRANTY IN
          SUCH STATEMENT OF WORK (INCLUDING SERVICE LEVEL AGREEMENTS), ARE IN
          LIEU OF ALL OTHER WARRANTIES, EXPRESS OR IMPLIED, OR WHETHER ARISING
          BY COURSE OF DEALING OR PERFORMANCE, CUSTOM, USAGE IN THE TRADE OR
          PROFESSION OR OTHERWISE, INCLUDING BUT NOT LIMITED TO, IMPLIED
          WARRANTIES OF

                                                                   Page 15 of 55
<PAGE>

          MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE OR WARRANTIES
          AGAINST INFRINGEMENT. Except for the warranties expressly set forth in
          this Section 15 and any Statement of Work, GENUITY acknowledges and
          agrees that it has relied on no other representations or warranties
          and that no other representations or warranties have formed the basis
          of its bargain hereunder.

     (e)  All representations, warranties and covenants of GTE contained in this
          Section shall continue for the term of this Agreement and shall
          survive its termination.

16.  ASSIGNMENT AND SUBCONTRACTING.

     (a)  Neither this Agreement nor any rights or obligations hereunder shall
          be assignable by either of the parties hereto; provided that GTE may
          delegate all or any portion of its obligations to perform Services
          under this Agreement to one or more of its affiliates or either party
          may assign to any affiliate without the consent of the other party.

     (b)  GTE may use subcontractors to perform the Services under this
          Agreement as specified in Section 1(d). GTE shall be responsible for
          the fulfillment of its obligations hereunder, notwithstanding the
          performance of such obligations by its subcontractors.

17.  EQUAL EMPLOYMENT.

     (a)  General Compliance.  Without limitation of Section 18, COMPLIANCE WITH
          ------------------
          LAWS, each party shall comply with applicable laws concerning
          employment, including, but not limited to the following, which are
          incorporated herein by specific reference:

          (1)  The Equal Employment Opportunity Clause set forth in Section 202,
               paragraphs I through 7, of Executive Order 11246, as amended,
               relative to Equal Employment Opportunity and the implementing
               Rules and Regulations of the Office of Federal Contract
               Compliance (hereinafter referred to as "the OFCCP") relating to
               equal employment opportunity.

          (2)  The Affirmative Action Clause set forth in Section 60-741.4 of
               the Affirmative Action Regulations on Handicapped Workers, issued
               by the OFCCP pursuant to Section 503 of the Vocational
               Rehabilitation Act of 1973, as amended.

                                                                   Page 16 of 55
<PAGE>

          (3)  The Affirmative Action Clause set forth in Section 60-250.4 of
               the regulations issued by the OFCCP under Section 402 of the
               Vietnam Era Veteran's Readjustment Assistance Act of 1974.

          (4)  Public Law 95-507 and Executive Orders 11625 and 12138.

          (5)  The Immigration Reform and Control Act of 1986 and any and all
               rules and regulations pertaining thereto. In compliance with the
               Act, GENUITY requires all approved contracting firms to supply
               only persons authorized to work in the United States pursuant to
               the Act. GTE shall be responsible for complying with the Act with
               regard to all employees supplied to GENUITY.

          (6)  Title I of the Americans with Disabilities Act, 42 U.S.C.A.
               12101 et seq.
                     ------

     (b)  ADA.  If any persons furnished by either party under the Agreement or
          ---
          any Statement of Work have a disability as defined in the Americans
          with Disabilities Act, 42 U.S.C.A. 12101 et seq. (the ADA), the
          furnishing party shall, where required by Title I of the ADA and at
          its sole expense, provide "reasonable accommodations" that may be
          required under Title I of the ADA. If GTE performs Services at
          facilities operated by GENUITY, GENUITY shall be responsible, at its
          sole expense, for any physical changes to GENUITY's facility that may
          be required under the ADA with respect to persons utilized by GTE in
          performing the Services.

     (c)  Work Environment.  Both parties agree to provide a work environment
          ----------------
          free from all forms of sexual harassment, including but not limited
          to, any unwelcome sexual advances, requests or demands for sexual
          favors, and other visual, verbal, or physical conduct of a sexual
          nature.

18.  COMPLIANCE WITH LAWS.

     GTE and GENUITY shall each comply with the provisions of all applicable
     federal, state, and local laws, ordinances, regulations and codes
     (including procurement of required permits or certificates) in fulfillment
     of their obligations under this Agreement.  The Confidential Information of
     each party may be subject to U.S. export and foreign transactions control
     regulations.  Each party undertakes that it will not export, nor cause nor
     permit to be exported, the other party's Confidential Information out of
     the United States of America without such other party's prior written
     consent and without compliance with applicable law and regulation; nor will
     such Confidential Information be made available, directly or indirectly,
     for use in any project associated with the design, development, production,
     testing, stockpiling or use of:  (a) nuclear weapons or facilities to
     produce nuclear explosives; or, (b) missiles; or, (c) chemical or
     biological warfare

                                                                   Page 17 of 55
<PAGE>

     agents. Each party agrees to comply with all applicable laws and
     regulations relating to the exportation of technical information, as they
     currently exist and as they may be amended from time to time.

19.  PLANT WORK RULES AND RIGHT OF ACCESS.

     (a)  Compliance.  Employees, subcontractors, and agents of the parties,
          ----------
          while on the premises of the other, shall comply with all plant rules,
          regulations and reasonable company standards for security, including
          (when required by U.S. government regulations) submission of
          satisfactory clearance from U.S. Department of Defense and other
          federal authorities concerned.

     (b)  Access.  Each party shall permit reasonable access during normal
          ------
          working hours to its facilities that are used in connection with the
          performance of Services. No charge shall be made for such visits.
          Reasonable prior notice shall be given when access is required.

     (c)  Limitation on Access.  If either party is given access, whether
          --------------------
          on-site or through remote facilities, to any computer or electronic
          data storage system of the other party in order to accomplish the
          Services called for in this Agreement, the party that receives such
          access shall limit such access and use solely to perform Services
          within the scope of this Agreement and shall not access or attempt to
          access any computer system, electronic file, software or other
          electronic services other than those specifically required to
          accomplish the Services required under this Agreement. Under no
          circumstances shall either party's personnel access any networks or
          facilities of the other party for the purpose of accessing other
          external networks, nor shall any such capabilities for such access be
          published or made known via any medium, as for example and not by way
          of limitation, posting on bulletin boards or E-mail. Any such use or
          publication shall be a material breach of this Agreement. Neither
          party shall use back doors, data capture routines, games, viruses,
          worms, or Trojan horses and any intentional introduction of such into
          the other party's data networks shall be deemed a material breach of
          this Agreement. The party receiving access shall limit such access to
          those of its employees whom the other party has authorized in writing
          to have such access in connection with this Agreement or the
          applicable Statement of Work, and shall strictly follow all security
          rules and procedures for use of the providing party's electronic
          resources. All user identification numbers and passwords and any
          information obtained as a result of access to and use of a party's
          computer and electronic data storage systems shall be deemed to be,
          and shall be treated as, Confidential Information under applicable
          provisions of this Agreement. Each party agrees to cooperate with the
          other in the investigation of any apparent unauthorized access to a
          party's computer or electronic data storage systems.

                                                                   Page 18 of 55
<PAGE>

20.  GENUITY RESPONSIBILITIES.

     GENUITY agrees to perform in a timely fashion those tasks, and to provide
     the personnel, facilities and accurate information as agreed by the parties
     and set forth in the applicable Statement of Work. GENUITY further agrees
     to cooperate with GTE in its performance of this Agreement, to not
     unreasonably withhold its consent to any matter for which consent is
     required or requested.

21.  PERMITS.

     Unless otherwise specifically provided for in this Agreement, GTE shall
     obtain and keep in full force and effect, at its expense, any permits,
     licenses, consents, approvals and authorizations ("Permits") necessary for
     and incident to the performance and completion of the Services.
     Notwithstanding the foregoing, GENUITY shall obtain and keep in full force
     and effect, at its expense, any Permits related to its facilities and the
     conduct of its business.

22.  PUBLICITY.

     The parties agree to submit to one another, for prior written approval, all
     advertising, sales promotion, press releases and other publicity matters
     relating to the Services performed pursuant to this Agreement, when its
     respective name or mark is mentioned or language from which the connection
     of said name or mark may be inferred or implied. The parties further agree
     not to publish or use such advertising, sales promotions, press releases,
     or publicity matters without such prior written approval. Any approval
     required under this Section shall not be unreasonably withheld or delayed
     by either party.

23.  TRADEMARKS, TRADENAMES AND OTHER INTELLECTUAL PROPERTY.

     Except as expressly set forth in this Agreement or in a separate written
     agreement between GTE and GENUITY, nothing in this Agreement or any
     Statement of Work shall grant, suggest or imply any right, license or
     authority for one party to use the name, trademarks, service marks, trade
     names or domain names of the other for any purpose whatsoever.  Except and
     to the extent expressly set forth in this Agreement or in a separate
     written agreement between GTE and GENUITY, nothing in this Agreement or any
     Statement of Work shall be deemed to grant to either party any right or
     license under any intellectual property of the other party.

                                                                   Page 19 of 55
<PAGE>

24.  TERMINATION.

     (a)  Termination Events.  Either party may terminate or cancel this
          ------------------
          Agreement or any Statement of Work, effective immediately, upon
          written notice to the other party, if any of the following events
          occur:

          (1)  The other files a voluntary petition in bankruptcy (other than as
               creditor).
          (2)  The other is adjudged bankrupt.

          (3)  A court assumes jurisdiction of the assets of the other under a
               federal reorganization act.

          (4)  A trustee or receiver is appointed by a court for all or a
               substantial portion of the assets of the other.

          (5)  The other becomes insolvent or suspends its business.

          (6)  The other makes an assignment of its assets for the benefit of
               its creditors except as required in the ordinary course of
               business.

     (b)  Termination for Breach.  Either party may terminate or cancel this
          ----------------------
          Agreement or a Statement of Work, for a material breach or default of
          any of the terms, conditions or covenants of this Agreement by the
          other, provided that such termination or cancellation may be made only
          following the expiration of a thirty (30) day period ("Cure Period")
          during which the breaching party has failed to cure such breach after
          having been given written notice thereof. In such event, the non-
          breaching party may terminate by giving 10 days written notice of
          termination, after the expiration of the Cure Period.

     (c)  Termination for Convenience.  GENUITY may terminate this Agreement
          ---------------------------
          or a Statement of Work during the term of this Agreement or a
          Statement of Work, for convenience on one hundred twenty (120) days
          prior written notice to GTE. In the event of termination by GENUITY
          pursuant to this Section, prior to the end of the term, GENUITY will
          reimburse GTE for all GENUITY-approved, third party costs for
          equipment or software which have been incurred by GTE after the
          execution of this Agreement as a direct result of GTE's provision of
          Services under this Agreement or any Statement of Work, provided that
          GENUITY shall be entitled to any right, license or title related to
          any such equipment or software to the extent GTE has the ability to
          convey such right, license or title.

                                                                   Page 20 of 55
<PAGE>

     (d)  Termination under Statement of Work.  Statements of Work may be
          -----------------------------------
          terminated as set out under their specific terms, if different from
          those set out in (a), (b) and (c) above.

25.  NOTICE.

     Any written notice either party may give the other concerning the subject
     matter of this Agreement shall be in writing and given or made by means
     that obtain a written acknowledgment of receipt.  If the notice pertains to
     a STATEMENT OF WORK performed by any of the following entities notice shall
     be sent to the applicable company addresses shown below, which may be
     changed by written notice:

     To GTE SERVICE CORPORATION:
               1255 Corporate Drive
               Irving, Texas 75038
               Attention:__________

     To GTE DATA SERVICES INCORPORATED:
               One East Telecom Parkway
               Temple Terrace, Florida 33637
               Attention:____________

     To GTE CONSOLIDATED SERVICES INCORPORATED:
               1255 Corporate Drive
               Irving, Texas 75038
               Attention:___________

     To GTE COMMUNICATION SYSTEMS INCORPORATED:
               5616 High Point
               Drive, Irving, Texas 75038
               Attention:_____________

     To GENUITY:
               3 Van de Graaff Drive
               Burlington, Massachusetts 01803
               Attention:_____________

     Notice shall be deemed to have been given or made when actually received,
     as evidenced by written acknowledgment of receipt.

                                                                   Page 21 of 55
<PAGE>

26.  WAIVER OF TERMS AND CONDITIONS.

     Failure to enforce any of the terms or conditions of this Agreement shall
     not constitute a waiver of any such terms or conditions, or of any other
     terms or conditions.

27.  SEVERABILITY.

     Where any provision of this Agreement is declared invalid, illegal, void or
     unenforceable, or any changes or modifications are required by regulatory
     or judicial action, and any such invalid, illegal, void or unenforecable
     provision, or such change or modification, substantially affects any
     material obligation of a party hereto, the remaining provisions of this
     Agreement shall remain in effect and the parties shall mutually agree upon
     a course of action with respect to such invalid provision or such change or
     modification to the end that the purposes of this Agreement are carried
     out.

28.  SURVIVAL OF OBLIGATIONS.

     The provisions in the Agreement relating to Confidentiality,
     Indemnification, Dispute Resolution, Termination, Compensation and Billing,
     Limitation of Liability, and Insurance shall survive any termination,
     cancellation or expiration of this Agreement.

29.  APPLICABLE LAW.

     This Agreement, and the rights and obligations contained in it, shall be
     governed by and construed in accordance with the laws of the State of New
     York, without regard to any conflicts of law principles that would require
     the application of the laws of any other jurisdiction.

30.  NO UNREASONABLE DELAY OR WITHHOLDING.

     Where agreement, approval, acceptance, consent or similar action by GENUITY
     or GTE is required, such action shall not be unreasonably delayed or
     withheld.

31.  ENTIRE AGREEMENT

     This Agreement represents the entire understanding between the parties with
     the respect to its provisions and cancels and supercedes all prior
     agreements or understandings, whether written or oral, with respect to the
     subject matter.  This Agreement may only be modified or amended by an
     instrument in writing signed by duly authorized representatives of the
     parties.  This Agreement shall be

                                                                   Page 22 of 55
<PAGE>

     deemed to include all Exhibits, Addenda and Statements of Work issued
     hereunder.

32.  RULES OF INTERPRETATION

     Headings in this Agreement are for convenience of reference only and shall
     not affect the interpretation or construction hereof.  Unless otherwise
     specified, (i) the terms "hereof", "herein" and similar terms refer to this
     Agreement as a whole and (ii) references herein to "Sections" refer to
     parts or sections of this Agreement.

IN WITNESS WHEREOF, the parties hereto have executed this Agreement through
their authorized representatives.

Genuity Solutions Inc.                  GTE Service Corporation

By:_____________________                By:_______________________
Name:___________________                Name:_____________________
Title:__________________                Title:____________________
Date:___________________                Date:_____________________

                                                                   Page 23 of 55
<PAGE>

                                                                    ATTACHMENT 1

                               STATEMENT OF WORK

                    ACCOUNTING AND CASH PROCESSING SERVICES
                    ---------------------------------------

This Statement of Work is appended to the Transition Services Agreement
("Agreement") dated ______________ by and between Genuity Solutions Inc. and GTE
Service Corporation and shall be governed by the terms and conditions thereof.
The services described herein shall be provided for a period of eight (8)
consecutive months after the Effective Date of the Transition Services
Agreement.

The purpose of this SOW is to provide for the transition of a variety of
accounting related services, since Genuity will not initially have in place the
infrastructure necessary to perform the services.  The services as described in
this SOW relate to accounts payable, payroll, cash processing, and asset
accounting.  Genuity desires to retain GTE to provide these services during a
transitional period while Genuity prepares itself to handle these services
independently of GTE.

Genuity understands and acknowledges that GTE plans to fulfill its obligations
hereunder utilizing the systems ("Systems") set out in the attached Exhibit A to
this Statement of Work, and agrees not to change its systems such that its
systems become incompatible with such Systems as long as this Statement of Work
is effective.

                           ACCOUNTS PAYABLE SERVICES

As requested, and at the discretion of Genuity, GTE will provide the following
Accounts Payable services:

1.   Perform all invoice and expense report processing for Genuity.

     .    Invoices for purchase order related items are mailed directly to
          Accounts Payable Shared Services Center ("AP/SSC") from the vendor.

     .    Expense reports and miscellaneous purchases are input into the system
          by the originator, then approved by the appropriate supervisor/manager
          and mailed to the AP/SSC.

     .    Expense reports are electronically processed, from submission to
          notification.

     .    Genuity electronic files are transmitted by Genuity and uploaded into
          system by accounts payable ("A/P").

2.   Work with Genuity purchasing group as required on issues related to payment
of purchase order related invoices, including resolution of invoices that do not
meet existing criteria for payment.

                                                                   Page 1 of 122
<PAGE>

3.   Print and distribute all checks for Genuity vendors nightly.

     .    Maintain appropriate level of security for the equipment and check
          stock.

4.   Perform vendor maintenance function to add new vendors and/or employees to
     the vendor file or change address information as needed. Mail out W-9 forms
     to all new vendors to obtain vendor's tax identification.

5.   Prepare 1099 forms at year-end.

6.   Administer field checking accounts for checks written at field locations.

     .    Maintain log of authorized check locations and signature file for each
          account.
     .    Print blank check stock and supplies to check locations when
          requested.

7.   Perform general ledger account reconciliations and bank reconciliations.

8.   Perform stop payment requests and provide status of checks as requested.
     Deposit vendor checks, refunds, returned checks, and other checks directly
     to the Genuity bank account and perform accounting accordingly.

9.   Establish and maintain recurring payments for leased property and other
     recurring items.

10.  Coordinate requirements for bank wire transfer payments in both foreign
     currency and US. Payments in foreign currency are coordinated with treasury
     department, which determines the exchange rate and provides the amount back
     to A/P in US dollars to journalize the transaction.

11.  All Genuity vouchers exceeding $150,000 will be reviewed prior to payment
     for compliance with Genuity payment policies and procedures. In addition, a
     post processing sample audit of approximately 8% of employee expense
     reports and 2% of other vouchers will be reviewed for compliance with
     Genuity's policies and procedures.

12.  Perform Electronic Funds Transfer ("EFT") for vendors and direct deposit
     for reimbursement of employee expense reports.

13.  Retain expense detail data as required by law that supports all required
     tax and regulatory obligations.

14.  Provide A/P payment services for international vendors.

     .    Foreign currency payment process
     .    General Ledger Accounting

15.  Cash management of payment cycles (i.e. vendor terms and year-end payment
     processing) as determined by Genuity.

16.  Process A/P adjustment forms for Prism related data changes.

17.  Provide ad-hoc vendor reporting.

                                                                  Page 2 of 122
<PAGE>

18.  Provide Genuity representatives electronic access to A/P scanned records.

19.  Provide state and use tax accruals set up and processing.

GTE will provide the following metrics to Genuity relating to accounts payable
------------------------------------------------------------------------------
services:
--------

1.   Invoice and expense report volumes.
     .    Provide monthly invoice and expense report volumes within 5 days
          following monthly expense cutoff.

2.   Average days to process invoice and expense reports through the standard
     and PME (procurement, match and error) queues.

     .    Until mechanical tracking is available, approximately 25 Genuity
          invoices/expense reports per week will be sampled to determine the
          average processing time. This information will be provided monthly
          within 5 days following expense cutoff. Mechanical tracking capability
          has been requested, and once functionality is available, will track
          processing time for all invoices and expense reports.

3.   Processing and response times on electronic feeds.
     .    A schedule will be developed (by A/P and system team) that will be
          provided to Genuity each day and a cumulative monthly summary showing
          files sent into The system by Genuity (including the date and timing
          of the transmission) and the date and times these files were actually
          processed into The system. Genuity will be required to notify both A/P
          and system processing each day of the number and kinds of files sent
          to verify that all files sent were actually received. This process is
          planned to be in place by May 1, 2000.

4.   General Ledger account reconciliations shall be prepared monthly by the
     15/th/ day of the second month following month end.  (i.e. by August 15 for
     the month of June.)

Genuity's Responsibilities with respect to Accounts Payable Services:
---------------------------------------------------------------------

Genuity shall provide all information/instructions regarding processing and
payment of invoices and expense reports.

Pricing Structure for Accounts Payable Services:
------------------------------------------------

Genuity shall pay GTE at the rate of $3.05 (three dollars and five cents) per
voucher or expense report for the first 250,000 vouchers and expense reports
processed in the 12-month period following the effective date of this Statement
of Work.  During this 12-month period, vouchers and expense reports exceeding
250,000 and up to 500,000, shall be charged at the rate of $1.80 each (one
dollar and eighty cents).  If the annual volume exceeds 500,000, a revised
charge per voucher shall be negotiated by GTE and Genuity.  If no agreement can
be reached, GTE shall not be required to process vouchers in excess of 500,000
per year.

Changes or requests that necessitate the use of manual efforts instead of
current system processes, or up-front meetings, conference calls, training,
consulting, or other similar services

                                                                   Page 3 of 122
<PAGE>

to be billed at the rate of $25.00 (twenty-five dollars) per hour, plus any
travel related costs if appropriate.

Any system cost increases attributable to Genuity, imposed by third party
vendors due to systems changes desired by Genuity such as license or user fees,
programming fees or maintenance fees, shall be paid by Genuity.

Programming/system work for new requirements or changes in systems to be billed
separately.

                               PAYROLL SERVICES

As requested, and at the direction of Genuity, GTE will provide the following
payroll services:

1.     Printing and distribution of payroll checks and advices.

2.     Manual checks provided as required.

3.     Calculate payment to employees based on a standard 40/80 hours each pay-
       period.

4.     Process exception time reported (overtime, shift hours and differential,
       on call hours and other work hours). Submission of exception information,
       via the time entry system or by direct feed from the Employee Time
       Reporting ("ETR") system into The system, is the responsibility of
       Genuity. Submission between any other electronic file format or means
       must be previously agreed to by Genuity and GTE.

5.     Process direct deposits.

6.     Process payroll taxes, including Federal, State and Local.

7.     Process employee deductions sent to the payroll center for inclusion in
       employee master file. Any change to existing benefits or third party
       vendors, or not flowing this information through the Quincy Processing
       Center in the same manner as is done as of the date hereof, will require
       programming and processing changes. These deductions include:
       .      Bond deductions
       .      Union dues
       .      Health Clubs
       .      Garnishments, Child support, Bankruptcy, IRS Levy deductions,
              and other
              such deductions
       .      United Way deductions
       .      Savings and Investment deductions (401K) from Fidelity
       .      FRP Plans - from Hewitt
       .      Insurance deductions - from Hewitt/KVI/MetLife
       .      Other miscellaneous deductions

8.     Process all additional earnings as transmitted to payroll center for
       payment and recording in employee earnings. Any change of outside vendors
       providing this information or not transmitting this information through
       the Quincy Processing Center in the same manner as is done as of the date
       hereof will require programming and processing changes. These items
       include:

                                                                  Page 4 of 122
<PAGE>

     .  Awards
     .  Discretionary Bonus
     .  Incentive Compensation payments
     .  Sales Incentives
     .  Retroactive payments
     .  Choices earnings - from Hewitt
     .  High Housing cost allowances
     .  Cost of Living adjustments
     .  Field Premiums
     .  Site Allowances
     .  Per Diem
     .  Sign on Bonus
     .  Option exercise earnings from Smith Barney
     .  Imputed Income
     .  Tuition aid
     .  Military pay/jury duty
     .  Other, as required

9.   Process Credit Union or Bank additions/changes/deletions.

10.  Process any termination pay, including vacation, retirement pay or other
     termination pay.

11.  Process vehicle allowance or usage for personal or company owned vehicles.

12.  Process tax gross-ups when required.

13.  Maintain earnings and deduction codes tables.

14.  Payment of employee deductions to appropriate vendors via check request to
     Accounts Payable. If A/P is not used by Genuity, programming and processing
     changes will be required.

15.  Process W-4s submitted by employees to payroll center.

16.  Provide all W-2 reporting requirements.

17.  Maintain check distribution codes.

18.  Reconcile payroll accounts.

19.  Transmit journal entry file per established schedule on system web page, to
     Genuity monthly to update its General Ledger.

20.  Process employee master file updates into payroll system when received from
     HR system.

21.  Continue to provide current system generated payroll reports.  Assist
     Genuity employees in determining RAMIS system report requirements.

                                                                   Page 5 of 122
<PAGE>

22.  An employee rate file will be transmitted daily (or as required) back to
     Genuity with adds/changes/deletes of employee rates for use in Genuity cost
     systems.

23.  Retain all data as required by law that supports normally required tax and
     regulatory obligations.

24.  Transmit journal entry file to Genuity biweekly for 401(k) employee match
     to update Genuity's general ledger.

25.  Reconcile all payroll interface and outerface files.

26.  Reconcile/provide summary funding report as required for treasury on
     Wednesday of pay-week.

27.  Provide appropriate system access to Genuity payroll personnel consistent
     with access as of the date hereof. (Additional access requirements will
     need to be coordinated with, and approved by HR/PR and system security.)

28.  Provide unemployment services with Gates MacDonald and keep rates updated
     in payroll system.  (A vendor change will require programming and process
     changes.)

29.  Provide employment verification and mortgage verification via TALX system.
     (Assumes Genuity contracts with TALX for this service. Changing the vendor
     will require programming and processing changes.)

GTE will provide the following metrics to Genuity with respect to payroll
services:

1.   Number of employees supported - based on average number of employees per
     pay period each month in a format to be mutually agreed upon by the
     parties.

2.   Number of manual checks each month to Genuity employees
     .  Number of checks
     .  Reason for manual checks (i.e. legal requirements, payroll error, time
        release issue, other reasons.)

3.   General Ledger account reconciliations prepared monthly by the 15/th/ day
     of the second month following month end. (i.e. by August 15 for the month
     of June)

Genuity's Responsibilities with respect to Payroll Services
-----------------------------------------------------------

Genuity is responsible for providing all information and data required for GTE
to perform its duties hereunder including, but not limited to, all employee
information, changes, pay information and other information through The human
resource systems (including benefit providers).

                                                                   Page 6 of 122
<PAGE>

Pricing Structure with respect to Payroll Services
--------------------------------------------------

Genuity shall pay GTE at a rate of $10.72 (ten dollars and seventy-two cents)
per employee supported per month.  All manual checks that are not the result of
legal requirements or payroll error are to be billed at the rate of $20.00
(twenty dollars) per check for the first 50 manual checks each month, $25.00
(twenty-five dollars) per check for the next 100 manual checks each month, and
$30.00 (thirty dollars) per check for all manual checks for the month exceeding
150, plus shipping and handling.

Changes or requests that necessitate the use of manual efforts instead of system
processes in effect as of the date hereof, or up-front meetings, conference
calls, testing, training or consulting to be billed at the rate of $25.00
(twenty-five dollars) per hour, plus any travel related costs if appropriate.

Any system cost increases attributable to Genuity, imposed by third party
vendors due to systems changes desired by Genuity such as license or user fees,
programming fees or maintenance fees, shall be paid by Genuity.

Programming/system work for new requirements or changes in systems to be billed
separately.

                           CASH PROCESSING SERVICES

As requested, and at the direction and under the policies developed and provided
by Genuity, GTE will provide the following administrative cash processing
services:

1.   Funding and Liquidity:

     .  Support and assist with bank selection process and negotiation of terms
        and conditions of bank facilities.

2.   Daily Cash Processing:

     .  Electronically poll banks to obtain balance and transaction data and
        report same to Genuity
     .  Concentrate cash flows from all sources pursuant to Genuity's
        instructions
     .  Transmit payment of all obligations via wire, ACH, EDI (including
        funding payroll and accounts payable) authorized by Genuity
     .  Administer short-term borrowing/investing activities pursuant to
        Genuity's policies and directions
     .  Provide efficient treasury management workstation which integrates and
        facilitates daily cash management and related accounting
        services/activities
     .  Provide cash activity research, as requested
     .  Provide supporting information and documentation to Genuity

3.   Cash Accounting and Reporting:

     .  Balance, journalize and upload:
        .  Receipts, disbursement transactions
        .  Temporary cash investments
        .  Short-term debt transactions

                                                                   Page 7 of 122
<PAGE>

        .  Long-term debt transactions
        .  Accruals, as necessary, related to the above
     .  Provide supporting information and documentation to Genuity
     .  Process transactions and maintain/provide documentation for payable and
        receivable transactions between and among Genuity subsidiaries and
        affiliated companies

4.   Bank Account Maintenance and Administration

     .  Provide routine bank account maintenance pursuant to Genuity banking
        resolutions, policies and direction:
        .  Open/close accounts
        .  Maintain accurate authorized signatory records and resolutions
        .  Ensure Genuity-directed internal controls are carried out
        .  Monitor efficiency of bank account structure and recommend changes
           for Genuity consideration, as needed

5.   Foreign Currency Exchange Transactions

     .  Maintain mechanized system for spot transactions under $250,000
     .  Execute foreign exchange, futures, and options transactions
     .  Prepare foreign exchange drafts and initiate wires

6.   International Project Finance

     .  Consult/advise on alternative sources of financing (OPIC, Exim, World
        Bank, and others)
     .  Provide support and assistance in executing international financing
        strategies

Genuity Responsibilities with respect to Cash Processing Services
-----------------------------------------------------------------

Genuity shall be responsible for providing instructions, policies, guidelines,
and board resolutions where applicable, and for selecting and maintaining
banking relationships such that GTE can perform its duties hereunder.

Pricing Structure with respect to Cash Processing Services
----------------------------------------------------------

Genuity shall pay GTE a one-time initial set-up fee of $11,000 (eleven thousand
dollars).

Genuity shall pay GTE an annual fee of $265,000 (two hundred sixty-five thousand
dollars) payable in monthly installments in arrears, for provision of the Cash
Processing Services described above in items 1-5 for the 12 month period
following the effective date of this Statement of Work.

Genuity shall pay any and all bank fees incurred by GTE on behalf of Genuity in
the course of delivering Services under this Statement of Work.

Genuity shall pay the following hourly rate for any Cash Processing Services
outside the scope of items 1-6 described above, including but not limited to
consulting or vendor transition services provided in the event Genuity elects to
utilize an alternative vendor at a later time: $65.00 (sixty-five dollars) per
hour.

                                                                   Page 8 of 122
<PAGE>

Genuity shall pay the following hourly rate for Services under 6 above
(International Project Finance): $100.00 (one hundred dollars) per hour.

Any system cost increases attributable to Genuity, imposed by third party
vendors due to systems changes desired by Genuity such as license or user fees,
programming fees or maintenance fees, shall be paid by Genuity.

                           ASSET ACCOUNTING SERVICES

GTE will provide the following asset accounting services for Genuity through its
Fixed Asset Shared Service Center:

Processes
---------

1.   Create asset detail records (monthly settlement procedures)
     .  Account for (settle) labor, material and overhead costs in accordance
        with settlement rules created by Genuity.
     .  Account for (settle) final assets, via manual or mechanical process for
        labor and materials costs, from internal orders and work breakdown
        structures ("WBS's") - Triggering of the settlement process will based
        upon one of the following:
        .  Technical close of an internal order ("IO") or WBS by Genuity
        .  Settlement rules established by Genuity
        .  Review of monthly "blanket" IO's and WBS's as identified by Genuity
        .  Receipt of summary information via TIMS system
        .  Receipt of notification of acceptance of Qwest Fiber segment
     .  Account for (settle) capital dollars relating to assets under
        construction during the month end close as directed by Genuity.

2.   Process transfers between locations, cost centers, and intra-legal entity
     company codes based upon input through the plant maintenance module and
     manual forms submitted by Genuity. Maintain documentation demonstrating
     support for the transfer of assets to Genuity defined standards.

3.   Calculate interest during construction amounts based upon Genuity policies
     and procedures, and place amounts into service based upon Genuity
     notification, or other established process.

4.   Process affiliate transfers (between Genuity legal entities) based upon
     information from Genuity. Maintain documentation demonstrating support for
     the transfer of assets to Genuity defined standards.

5.   Process retirements of assets based upon information supplied by Genuity.
     Maintain documentation supporting the retirement of assets to Genuity
     defined standards.

6.   Record proceeds from the sale of assets, based upon cash receipts
     information booked by Genuity.

                                                                   Page 9 of 122
<PAGE>

7.   Generate depreciation expense monthly according to the Genuity established
     calendar, including:
     .  Running system depreciation program
     .  Addressing any errors and posting to the general ledger
     .  Reconciling and resolving any sub-ledger to general ledger discrepancies

8.   Perform year-end rollover processes.

Data Maintenance
----------------

1.   Maintain and update location code information as required by Genuity.

2.   Maintain adequate data to support internal and external audit requests
     along with tax and insurance requirements, in accordance with Genuity
     policies and procedures.

Reporting
---------

1.   Ensure access to monthly activity reports including asset history sheets
     with acquisition, transfer, retirement and depreciation information.

2.   Ensure access to month end asset detail positions.

3.   Support ad-hoc reporting requests from Genuity.

4.   Provide required reporting for year-end tax processes plus required
     property tax and insurance reporting, as defined by the Genuity tax and
     insurance groups.

5.   Provide reconciliations of all asset accounting tracked accounts and
     procedures (i.e., interest during construction) monthly by the 15/th/ of
     the month.

Ad-hoc Services
---------------

1.   Maintain lease term schedule for leasehold information based upon
     information from the facilities group.

2.   Support capital lease related requirements for tracking and reporting.

3.   Support revaluations of assets and other like special projects as required
     by Genuity.

4.   Supply supporting documentation as maintained.

5.   Work with the system development team to implement any Genuity or GTE
     desired upgrades or enhancements involving the system fixed asset module.

6.   Support audit requests (including interface with other shared service
     centers ("SSC's") for external and internal audit groups, including system
     and process reviews, and sample detail testing in accordance with pre-
     defined schedules.

                                                                  Page 10 of 122
<PAGE>

Service Level Standards
-----------------------

1.  All assets under construction ("AUC") amounts that are triggered (under
    Processes-first section above) for transfer to final assets by the 15/th/ of
    the month are expected to be depreciable assets for the given month end
    close. Any items not processed are to be reported through a backlog tracking
    process.

2.  Asset records will be created to the level of detail procedurally defined by
    Genuity.

3.  Transfers, retirements, sales and affiliate transactions are transmitted to
    the SSC by the 15/th/ of the month and are expected to be booked prior to
    the given month end close.

4.  Location database updates will be provided on a 24-hour turnaround.

5.  A depreciation roll-forward is expected for each month by the 3/rd/ business
    day after the posting of depreciation. This roll-forward should document the
    change in depreciation by company code broken out by the impact of
    additions, fully depreciated assets, and retirements.

6.  Support document retrieval for records on transfers, affiliate sales, and
    retirements will be provided on a 48-hour turn-around basis.

Pricing Structure with respect to Asset Accounting Services:
------------------------------------------------------------

Genuity shall pay GTE a monthly fee of $42,000 for the Services described
herein.

Changes or requests that necessitate the use of manual efforts instead of
current system processes, or up-front meetings, conference calls, training,
consulting, or other similar services to be billed at the rate of $25.00
(twenty-five dollars) per hour, plus any travel related costs if appropriate.

Any system cost increases attributable to Genuity, imposed by third party
vendors due to systems changes desired by Genuity such as license or user fees,
programming fees or maintenance fees, shall be paid by Genuity.

GTE SERVICE CORPORATION                      GENUITY SOLUTIONS INC.

By:___________________________               By:________________________

Title:________________________               Title:_____________________

Date:_________________________               Date:______________________

                                                                  Page 11 of 122
<PAGE>

Exhibit A

Note:  The sheets included in the Excel worksheet file referenced above are
attached to this document immediately following this page.

                                                                  Page 12 of 122
<PAGE>

                               STATEMENT OF WORK
                               -----------------

                           HUMAN RESOURCES SERVICES
                           ------------------------

This Statement of Work ("SOW") is appended to the agreement dated ____________,
2000, by and between Genuity Solutions Inc. ("Genuity") and GTE Service
Corporation ("GTE") and shall be governed by the terms and conditions thereof.
The services described herein shall be provided by GTE to Genuity for a period
of three months beginning on the date of the agreement.

SUMMARY:

GTE administers human resources matters in an efficient and centralized manner
and wishes to make this administrative expertise available to Genuity so that
employees experience an orderly transition from GTE to Genuity. Similarly,
Genuity wishes to retain access to certain aspects of GTE's human resources
administrative expertise until such time as Genuity can develop its own
expertise in this area. Accordingly, GTE and Genuity are entering into this SOW,
which will govern the parties' relationship with respect to various human
resources matters, including employee benefits services, general human resources
administrative services, employee data warehousing, development of a company
intranet, health and welfare benefits funding matters, and development of a
benefits delivery system. By its terms, this SOW will govern the parties
relationship in this regard for a period of three months from the date of the
agreement between GTE and Genuity. However, it is anticipated that this SOW will
be extended through December 31, 2000. Under the terms of this SOW, GTE shall
have no role in hiring or terminating Genuity employees.

EMPLOYEE BENEFITS SERVICES:

For the purposes of this document, "Employee Benefits Plans" is comprised of,
and limited to the following: CHOICES health, dental, disability, FRP, HMO,
DHMO, Life Insurance, AD&D, prescription, vision, adoption assistance, personal
lines of insurance, survivor support programs and long term care.

1.   Provide assistance to Genuity on an as needed basis in performing various
     administrative functions under employee benefit plans.

     .  Consult with Genuity on administrative interpretations of employee
        benefit plan provisions.

     .  Provide Genuity with information regarding historical practices with
        regard to employee benefit plan administration.

Note:  The above benefits-related information is not accessible via a GTE web
                                                 ---
site.

                                                                   Page 1 of 155
<PAGE>

Genuity's Responsibilities with respect to Employee Benefits Services
---------------------------------------------------------------------

Genuity understands and agrees that any involvement by GTE with Genuity's
employee benefit plans will be in an advisory or consultative capacity and not
                                                                           ---
in a fiduciary capacity. This includes, but is not limited to the Claims and
Appeals processes. As between GTE and Genuity, all fiduciary responsibility and
accountability remains at all times with Genuity.

Genuity will act as the point of contact with all vendors for any matter
relating to fiduciary and plan design issues, with GTE acting merely in an
advisory or consultative capacity. GTE will act as the point of contact with all
vendors for all other issues.

Genuity shall provide all information/instruction regarding its employees,
employee benefit plans, and vendors as GTE may require to fulfill its
obligations.

Genuity agrees to provide a quarterly report of all former GTE employees that
terminate or retire from Genuity. This information should be provided to the
Director, Executive Compensation Administration and Director, Benefits
Administration. This information will be used to ensure these employees receive
any appropriate GTE benefits as a result of their prior GTE service.

Pricing Structure for Employees Benefits Services
-------------------------------------------------

GTE COSTS:

Genuity shall pay GTE at a rate of $5,400 per month, plus any travel expenses
incurred.

Programming or system work for any employee benefits administrative services to
be billed separately at a rate to be mutually agreed upon.

Genuity will pay GTE actual costs incurred resulting from any GTE system
modifications for Genuity-specific administrative or plan design changes.

EXTERNAL VENDOR COSTS:

Genuity will pay GTE's costs for any increased vendor charges (directly to the
vendor, unless otherwise specified) associated with Genuity-specific
administrative or plan design changes. Additionally, Genuity will be invoiced
separately for regular, ongoing administrative services provided by vendor, for
the exclusive benefit of Genuity.

                                                                   Page 2 of 155
<PAGE>

OTHER HUMAN RESOURCES ADMINISTRATIVE SERVICES

1.   Provide assistance to Genuity on an as needed basis in accomplishing
     various other administrative human resources services including:

     .  Training Administration: training registration and scheduling, shipment
        of training materials and other miscellaneous support for Genuity
        employees on an as-needed basis;

     .  Educational Assistance Administration;

     .  Relocation Services Administration; and

     .  Although no other specific services will be provided by GTE in the areas
        of Employee Services Operations or Support, other than those
        specifically described herein, it is anticipated that some amount of
        transition support, as well various technical support will be required
        by Genuity on an as needed basis.

                                                                   Page 3 of 155
<PAGE>

Pricing Structure:
-----------------

Genuity will pay actual vendor costs incurred for the delivery of these services
and will pay GTE's costs for any increased vendor charges (directly to the
vendor, unless otherwise specified) associated with Genuity-specific
administrative or plan design changes.

For Training Administration Services, Genuity shall pay GTE at a rate of $25.00
per hour, plus any travel expenses incurred, to be invoiced monthly.

For Employee Services Operations/Support transitional and/or technical support,
Genuity shall pay GTE at a rate of $40.00 per hour, plus any travel expenses
incurred, to be invoiced monthly.

Programming or system work for any administrative services to be billed
separately at a rate to be mutually agreed upon.

Genuity will be billed separately for actual costs incurred by GTE for any GTE
system modifications for Genuity-specific administrative or program design
changes.

                                                                   Page 4 of 155
<PAGE>

2.   Provide support in the area of Workforce Development, specifically related
     to providing non-strategic course development and delivery on an as-needed
     basis

Pricing Structure:
-----------------

Genuity shall pay GTE the following rates on an as needed basis:

Programming or system work for any administrative services to be billed
separately at a rate to be mutually agreed upon.

                                                       --------------------
                                                               Price
                                                            Per Student
                                                               Hour
---------------------------------------------------------------------------
Sales & Marketing Delivery                              $              40
MMDP (Marketing Mgmt Development Program) Delivery      $              46

Technical Delivery                                      $              15

IT Training                                             $              37

Management Delivery                                     $              30

----------------------------------------------------------------------------

----------------------------------------------------------------------------
Curriculum Maint. & Development ($/curriculum
                                 developer hour)        $              85
(Represents average cost and is subject to adjustment
based on project)
----------------------------------------------------------------------------

----------------------------------------------------------------------------
Alternative Delivery License Fees                          Annual Cost
                                              SkillSoft $          71,625
                                  NETg/Smartforce/Other $         262,259
----------------------------------------------------------------------------

----------------------------------------------------------------------------
Leadership Development                                     Per Session
----------------------------------------------------------------------------
                                LDW LD Workshop (1 day) $          14,888
                         LDM LD for Management (3 days) $          56,107
  LDC LD for Coaches & Individual Contributors (2 days) $          20,523
                  LDS LD for Senior Executives (2 days) $          50,512

----------------------------------------------------------------------------

Genuity will be billed separately for actual costs incurred by GTE for any GTE
system modifications for Genuity-specific administrative or program design
changes or software changes.

3.   Employee Opinion Survey (Viewpoints)

     .   Conduct Employee Opinion Surveys on behalf of Genuity utilizing current
         process and program.

     .   Genuity will be administered as part of the main Viewpoints study.

                                                                   Page 5 of 155
<PAGE>

     .   Includes monthly distribution and reporting (approximately 300 per
         month, 3,600 annually)

Pricing Structure:
-----------------

Genuity shall pay GTE as follows:

<TABLE>
<CAPTION>
------------------------------------------------------------------------------------------------
                                        DUE                             COST
------------------------------------------------------------------------------------------------
<S>                                     <C>                             <C>
 Initial set-up costs including         One Time                        $1,000
 questionnaire and  Internet
 Survey revisions
------------------------------------------------------------------------------------------------
 Basic Study Costs                      Monthly                         $1,200
------------------------------------------------------------------------------------------------
 Printing, paper,                       Monthly                         $  150
 communication, promotion
------------------------------------------------------------------------------------------------
 TOTAL                                                                  One Time: $1,000
                                                                        Ongoing/monthly: $1,350
------------------------------------------------------------------------------------------------
</TABLE>

Programming or system work for any employee opinion survey services to be billed
separately at a rate to be mutually agreed upon.

Genuity will be billed separately for actual costs incurred by GTE for any GTE
system modifications for Genuity-specific administrative or program design
changes or software changes.

Genuity's Responsibilities with respect to Other Human Resources Administrative
-------------------------------------------------------------------------------
Services
--------

Genuity understands and agrees that any involvement by GTE with Genuity's other
Human Resources Administrative Services will be in an advisory or consultative
capacity and not in a fiduciary capacity. As between GTE and Genuity, all
             ---
fiduciary responsibility and accountability remains at all times with Genuity.

Genuity will act as the point of contact with all vendors for any matter
relating to fiduciary and plan design issues, with GTE acting merely in an
advisory or consultative capacity. GTE will act as the point of contact with all
vendors for all other issues.

EMPLOYEE DATA WAREHOUSE DEVELOPMENT AND SUPPORT:

1.   Develop Employee Data Warehouse logical view for Genuity Employees.

     .  Data will be a subset of GTE Employee Data Warehouse data elements

     .  Data will initially consist of SAP current and chronological history
        only

                                                                   Page 6 of 155
<PAGE>

     .  The data will be a direct extract from source systems and will have
        minimal cleanup

     .  Connectivity via ODBC will be provided to Genuity who will be
        responsible for their own reporting tools

2.   Maintain Employee Data Warehouse View for Genuity and provide Help Desk
     support on an as needed basis.

     .  Provide regular feeds to Genuity Employee Data Warehouse View from SAP

     .  Make minor changes to view data elements and structure

     .  Maintain security profiles and provide access to the Employee Data
        Warehouse

     .  Provide first level help desk support for questions on connectivity

     .  Provide option to Genuity to incorporate new data elements and
        functionality in their Employee Data Warehouse view if and when they do
        become available in the GTE Employee Data Warehouse. The cost will be
        negotiated separately.

     .  Cost does not include training which will be negotiated separately.

                                                                   Page 7 of 155
<PAGE>

Pricing Structure for Employee Data Warehouse Development and Support:
---------------------------------------------------------------------

The pricing quoted below takes into account the work involved in providing the
following services:

Development

Obtain and map required data elements
Create logical data view
Provide load balancing
Test logical data view
User Acceptance Testing (UAT)
Assign security profiles and give users access to view
Provide ODBC connectivity

Annual Support

First level help desk for questions on connectivity
Periodic refresh of view (Periodicity TBC)
Backup and Recovery support
Add new authorized user to view
Add new security profiles

------------------------------------------------------------------------------
          Item                        Cost Category         Total Price
------------------------------------------------------------------------------

 .  Annual Support Costs
    ($3,383/month)                 RECURRING                  $40,590
                                   (ANNUAL)
-----------------------------------------------------------------------------

 .  Development
                                   ONE TIME                   $16,667
-----------------------------------------------------------------------------

 .  Total Price - first year                                  $57,257
-----------------------------------------------------------------------------

Genuity will pay an additional amount to be negotiated separately if it needs
any data element not in the current GTE Employee Data Warehouse or additional
functionality not outlined in the current document.

HR.GTE.COM:

For the purposes of this document, "HR.GTE.COM" is comprised of, and limited to
the following: Intranet Website shell with design, navigation, and Icons, for
page levels zero and one.

                                                                   Page 8 of 155
<PAGE>

Assumptions:
1.   No outerface links will be provided under this SOW.
2.   No specific content will be included under this SOW. Note: All hr.gte.com
     content is deemed to be GTE proprietary and will not be covered by this
     SOW.
3.   This SOW includes a one-time copy of existing homepage and level one page
     structures only.
4.   Education & Training and Career Development and Training (CDAT) content and
     functionality are not covered under this SOW. This can be explored with and
     provided by Jim Roach.
5.   No other specific services will be provided by GTE in the areas of
     HR.GTE.COM Operations or Support.

Pricing Structure for HR.GTE.COM:
--------------------------------

GTE Prices: All prices associated with this SOW are based on the number of hours
to create and deliver a shell version of hr.gte.com.

Pricing Structure: Genuity shall pay the following one-time costs:

---------------------------------------------------------------------------
             Item                       Cost Category        Total Price
---------------------------------------------------------------------------
 .   Initial Setup Level Zero through
    One pages of hr.gte.com
    production site                      ONE TIME                $2,837

 .   Place shell on separate
    environment and quality assure
    product
 .   Package product for shipment
---------------------------------------------------------------------------

 .   Total Price                                                  $2,837
---------------------------------------------------------------------------

HEALTH & WELFARE FUNDING SERVICES:

1.   Provide administrative support to Genuity for employee Benefit Finance
     Information System (BFIS).

     .  Input continually updated enrollment information into BFIS.

     .  Calculate monthly premiums to be paid to trust/custodial account.

     .  Calculate amounts paid by trust/custodial account to vendors.

     .  Monitor claims paid by custodial account to self-insured vendors and
        report activity to Genuity.

     .  Advise self-insured vendors of administrative expense amounts generated
        by the self-bill process.

                                                                   Page 9 of 155
<PAGE>

     .  Maintain BFIS internal tables consistent with Genuity plan design.

     .  Provide management reports to maintain health care plan performance.

     .  Provide report of year-end claims outstanding.

2.   Provide administrative support to Genuity with regard to its health and
     welfare trust or custodial account.

     .  Calculate monthly payments to and from trust/custodian.

     .  Execute payments from trust/custodian.

     .  Reconcile trust activity between Genuity and the trustee/custodian.

3.   Provide Genuity with benefit accounting guidance, cost analysis, and
     funding strategies.

     .  Estimate annual cost and funding based on plan design and past
        experience (to be used for budget and strategic plan projections).

     .  Estimate annual cash commitments.

4.   Provide Genuity with financial analysis for employee benefit plan financial
     analysis.

     .  Provide historical data from BFIS database to support benefit plan
        financial analysis.

5.   Oversee the completion of annual governmental reporting obligations.

     .  Prepare Form 5500 (Annual Report) for all ERISA-governed employee
        benefit plans required to file Form 5500 each year.

     .  Prepare Summary Annual Reports (SARs) as required.

     .  Prepare Form 990 as required.

Genuity's Responsibilities with respect to Health & Welfare Funding Services
----------------------------------------------------------------------------

Genuity understands and agrees that any involvement by GTE with Genuity's
employee benefit plans will be in an advisory or consultative capacity and not
                                                                           ---
in a fiduciary capacity. As between GTE and Genuity, all fiduciary
responsibility and accountability remains at all times with Genuity.

Genuity shall provide all information/instruction regarding its employees,
employee benefit plans, and vendors as GTE may require to fulfill its
obligations.

                                                                  Page 10 of 155
<PAGE>

Genuity understands and agrees that any proposed changes to plan design or
vendor choice must be compatible with BFIS.

Pricing Structure for Health & Welfare Funding Services
-------------------------------------------------------

            Item                       Cost Category          Amount
----------------------------------------------------------------------------

 .   Health & Welfare Benefits
    Funding Annual Charge               RECURRING             $40,500

----------------------------------------------------------------------------

 .    Initial Set Up Costs to
     Establish Genuity as a
     Separate Entity                    ONE TIME              $20,500

----------------------------------------------------------------------------

 .   Total                                                     $61,000
----------------------------------------------------------------------------

Genuity will pay an additional amount to be negotiated separately if GTE cannot
use BFIS to complete its obligations or if any third parties do not continue to
perform their current duties or if additional vendor charges (e.g., software
usage) are imposed upon GTE.

QUINCY PROCESSING CENTER - BENEFITS DELIVERY SYSTEM

For the purposes of this SOW, Benefits Delivery System represents the system
that interfaces with the GTE Payroll systems and the benefit plan vendors as
listed below.

                                                                  Page 11 of 155
<PAGE>

SERVICES
---------

1.   Reconcile and control interfaces from GTE SAP Payroll system

2.   Authorize funds transfers to benefit vendors.

3.   Edit and post data to the Benefits Delivery System Data Base.

4.   Process manual payments and adjustments.

5.   Create outerfaces to vendors based on their specific data requirements,
     file formats, and timing requirements.

       Fidelity Investments
       KVI
       MetLife
       Smith Barney
       Federal  & State Political Action Committee (PAC)
       Hewitt Associates
       AYCO
       TALX
       CORE
       Cendant
       Arthur Andersen
       Edcor
       Other vendors to be mutually agreed upon

6.   Receive and process interface from vendors to GTE Payrolls.

ASSUMPTIONS
-----------

 .  There will be no physical separation of data on the QPC Benefits Delivery
   System (BDS).
 .  Assume no vendor changes.
 .  Assume that Flexible Benefit dollars (GUL, PLP/LTC, FRP, PAC) for Genuity can
   be co-mingled with GTE Flex Ben $ on one interface to the vendors. If a
   separate interface is required to vendors for Genuity information and
   dollars, then a new development SOW would be required.
 .  Assume a separate reconciliation for Genuity.
 .  Assume that the QPC may potentially submit subsequent SOWs as details of the
   Genuity benefits become more defined. At that time, we will evaluate what
   additional time and costs will be necessary in order to provide the agreed
   upon services.

                                                                  Page 12 of 155
<PAGE>

Pricing:
--------

-----------------------------------------------------------------------------
          Item                     Cost Category               Total Price
-----------------------------------------------------------------------------
 .   Benefit Delivery System
    Operations ($88,883/month)      RECURRING                  $1,066,594

-----------------------------------------------------------------------------

 .   Total Price (Annual)                                       $1,066,594
-----------------------------------------------------------------------------

QUINCY PROCESSING CENTER: PENSTAR INTERFACE SYSTEM (INTERFACE TO GTE'S PENSION
CALCULATION SYSTEM AT HEWITT)

SERVICES:

None

ASSUMPTIONS
-----------

The QPC will not track hours and earnings for the Genuity employees.
Hewitt will the employees that are due future GTE Pensions.

COSTS
-----

None

QUINCY PROCESSING CENTER - PENSION PAYROLL SYSTEM:

Services
--------

None

ASSUMPTIONS
-----------

No retirees transfer to Genuity and there are no new retirees.

COSTS
-----

None

                                                                  Page 13 of 155
<PAGE>

GENERAL ASSUMPTIONS

General SOW Assumptions/Provisions for Employee Data Warehouse Development and
Support, HR.GTE.COM, Quincy Processing Center--Benefits Delivery System, Quincy
Processing Center: Penstar Interface System (Interface To Gte's Pension
Calculation System At Hewitt), and Quincy Processing Center--Pension Payroll
System:

1.   The HR/Payroll tasks are outlined in several SOWs. HR Technology and
     Information Services tasks in support of non-SAP systems are outlined
     within this SOW. HR Technology and Information Services tasks in support of
     the SAP System are covered under the SAP SOW. Payroll Service Center (PSC)
     tasks are outlined in Finance Functional SOW.

2.   The HR SOWs assume that all services performed for Genuity will continue in
     a similar manner as performed today unless otherwise noted. Only those
     tasks outlined within this SOW shall be performed. Any tasks not outlined
     within this SOW would require a contractual direction from the GTE Account
     Manager.

3.   (GTE Account Manager) is the Genuity point of contact for all contractual
     matters related to this SOW. Any requests for any changes to tasks or new
     functionality should be forwarded in writing to (GTE Account Manager).

4.   The estimates outlined in this SOW assume support for 3,800 Genuity
     employees. If this number increases, the resources assigned to support
     Genuity would need to be reassessed.

5.   It is expected that there will be several changes to the work outlined
     within these SOWs over the next several weeks as benefit plans and other
     specific Genuity processes become finalized. A key point to remember is
     that these types of changes cannot be implemented overnight.

6.   Maintenance tasks within this SOW are for minor Business As Usual (BAU)
     tasks in support of production. If there are any BAU changes/modifications
     beyond minor maintenance, such as mass re-organizations, benefit plan
     changes, new functionality, etc., these changes/modifications will be
     incorporated into a new development SOW. Specific tasks, prices and
     schedules would be developed for the agreed upon SOW.

7.   Genuity agrees to review HR audit reports and act upon any errors
     identified in a timely manner to ensure data integrity within the system
     and with downstream vendors.

8.   Upgrades/Enhancements: For any systems where a common development
     environment exists, e.g., SAP, Employee Data Warehouse (EDW), Quincy
     Processing Center (QPC) systems, agrees to abide by the standards, changes,
     upgrades, and enhancements that have been, or will be, developed and

                                                                  Page 14 of 155
<PAGE>

     implemented across the environment. A proportion of the on-going
     development tasks will be apportioned to Genuity in the same manner as
     production costs as allocated. Examples include Employee Self Service (ESS)
     enhancements, Manager's Desktop, On-line Org Charts. Genuity will
     participate in a user forum to assist in prioritizing these enhancements.

     Should Genuity desire to not abide by, and share appropriate costs for, the
     baseline system configuration and associated upgrades and enhancements, a
     completely separate physical environment for Genuity would be warranted.
     GTE would be pleased to develop a technical and cost proposal for such work
     at the request of Genuity.

9.   This SOW highlights both production tasks and one-time development tasks
     that must also be performed to set up or establish the systems environment
     for Genuity.

     GTE SERVICE CORPORATION            GENUITY SOLUTIONS INC.

By:___________________________      By:___________________________

Title:__________________________    Title:__________________________

                                                                  Page 15 of 155
<PAGE>

                                                                    ATTACHMENT 2

                               STATEMENT OF WORK
                               -----------------

                            HUMAN RESOURCES SERVICES
                            ------------------------

This Statement of Work ("SOW") is appended to the agreement dated ____________,
2000, by and between Genuity Solutions Inc. ("Genuity") and GTE Service
Corporation ("GTE") and shall be governed by the terms and conditions thereof.
The services described herein shall be provided by GTE to Genuity for a period
of three months beginning on the date of the agreement.

SUMMARY:

GTE administers human resources matters in an efficient and centralized manner
and wishes to make this administrative expertise available to Genuity so that
employees experience an orderly transition from GTE to Genuity. Similarly,
Genuity wishes to retain access to certain aspects of GTE's human resources
administrative expertise until such time as Genuity can develop its own
expertise in this area. Accordingly, GTE and Genuity are entering into this SOW,
which will govern the parties' relationship with respect to various human
resources matters, including employee benefits services, general human resources
administrative services, employee data warehousing, development of a company
intranet, health and welfare benefits funding matters, and development of a
benefits delivery system. By its terms, this SOW will govern the parties
relationship in this regard for a period of three months from the date of the
agreement between GTE and Genuity. However, it is anticipated that this SOW will
be extended through December 31, 2000. Under the terms of this SOW, GTE shall
have no role in hiring or terminating Genuity employees.

EMPLOYEE BENEFITS SERVICES:

For the purposes of this document, "Employee Benefits Plans" is comprised of,
and limited to the following: CHOICES health, dental, disability, FRP, HMO,
DHMO, Life Insurance, AD&D, prescription, vision, adoption assistance, personal
lines of insurance, survivor support programs and long term care.

1.  Provide assistance to Genuity on an as needed basis in performing various
    administrative functions under employee benefit plans.

    .  Consult with Genuity on administrative interpretations of employee
       benefit plan provisions.

    .  Provide Genuity with information regarding historical practices with
       regard to employee benefit plan administration.

Note:  The above benefits-related information is not accessible via a GTE web
                                                 ---
site.

                                                                   Page 1 of 155
<PAGE>

Genuity's Responsibilities with respect to Employee Benefits Services
---------------------------------------------------------------------

Genuity understands and agrees that any involvement by GTE with Genuity's
employee benefit plans will be in an advisory or consultative capacity and not
                                                                           ---
in a fiduciary capacity. This includes, but is not limited to the Claims and
Appeals processes. As between GTE and Genuity, all fiduciary responsibility and
accountability remains at all times with Genuity.

Genuity will act as the point of contact with all vendors for any matter
relating to fiduciary and plan design issues, with GTE acting merely in an
advisory or consultative capacity. GTE will act as the point of contact with all
vendors for all other issues.

Genuity shall provide all information/instruction regarding its employees,
employee benefit plans, and vendors as GTE may require to fulfill its
obligations.

Genuity agrees to provide a quarterly report of all former GTE employees that
terminate or retire from Genuity. This information should be provided to the
Director, Executive Compensation Administration and Director, Benefits
Administration. This information will be used to ensure these employees receive
any appropriate GTE benefits as a result of their prior GTE service.

Pricing Structure for Employees Benefits Services
-------------------------------------------------

GTE COSTS:

Genuity shall pay GTE at a rate of $5,400 per month, plus any travel expenses
incurred.

Programming or system work for any employee benefits administrative services to
be billed separately at a rate to be mutually agreed upon.

Genuity will pay GTE actual costs incurred resulting from any GTE system
modifications for Genuity-specific administrative or plan design changes.

EXTERNAL VENDOR COSTS:

Genuity will pay GTE's costs for any increased vendor charges (directly to the
vendor, unless otherwise specified) associated with Genuity-specific
administrative or plan design changes. Additionally, Genuity will be invoiced
separately for regular, ongoing administrative services provided by vendor, for
the exclusive benefit of Genuity.

                                                                   Page 2 of 155
<PAGE>

OTHER HUMAN RESOURCES ADMINISTRATIVE SERVICES

1.  Provide assistance to Genuity on an as needed basis in accomplishing various
    other administrative human resources services including:

    .   Training Administration: training registration and scheduling, shipment
        of training materials and other miscellaneous support for Genuity
        employees on an as-needed basis;

    .   Educational Assistance Administration;

    .   Relocation Services Administration; and

    .   Although no other specific services will be provided by GTE in the areas
        of Employee Services Operations or Support, other than those
        specifically described herein, it is anticipated that some amount of
        transition support, as well various technical support will be required
        by Genuity on an as needed basis.

                                                                   Page 3 of 155
<PAGE>

Pricing Structure:
-----------------

Genuity will pay actual vendor costs incurred for the delivery of these services
and will pay GTE's costs for any increased vendor charges (directly to the
vendor, unless otherwise specified) associated with Genuity-specific
administrative or plan design changes.

For Training Administration Services, Genuity shall pay GTE at a rate of $25.00
per hour, plus any travel expenses incurred, to be invoiced monthly.

For Employee Services Operations/Support transitional and/or technical support,
Genuity shall pay GTE at a rate of $40.00 per hour, plus any travel expenses
incurred, to be invoiced monthly.

Programming or system work for any administrative services to be billed
separately at a rate to be mutually agreed upon.

Genuity will be billed separately for actual costs incurred by GTE for any GTE
system modifications for Genuity-specific administrative or program design
changes.

                                                                   Page 4 of 155
<PAGE>

2.  Provide support in the area of Workforce Development, specifically related
    to providing non-strategic course development and delivery on an as-needed
    basis

Pricing Structure:
-----------------

Genuity shall pay GTE the following rates on an as needed basis:

Programming or system work for any administrative services to be billed
separately at a rate to be mutually agreed upon.

                                                              -----------------
                                                                   Price
                                                                Per Student
                                                                    Hour
-------------------------------------------------------------------------------
Sales & Marketing Delivery                                      $           40
MMDP (Marketing Mgmt Development Program) Delivery              $           46

Technical Delivery                                              $           15

It Training                                                     $           37

Management Delivery                                             $           30

-------------------------------------------------------------------------------
-------------------------------------------------------------------------------
Curriculum Maint. & Development ($/curriculum developer hour)   $           85
(Represents average cost and is subject to adjustment based
on project)
-------------------------------------------------------------------------------
-------------------------------------------------------------------------------
Alternative Delivery License Fees                                  Annual Cost
                                                     SkillSoft  $       71,625
                                         NETg/Smartforce/Other  $      262,259
-------------------------------------------------------------------------------
-------------------------------------------------------------------------------
Leadership Development                                             Per Session
-------------------------------------------------------------------------------
                                       LDW LD Workshop (1 day)  $       14,888
                                LDM LD for Management (3 days)  $       56,107
         LDC LD For Coaches & Individual Contributors (2 days)  $       20,523
                          LDS LD for Senior Executive (2 days)  $       50,512
-------------------------------------------------------------------------------

Genuity will be billed separately for actual costs incurred by GTE for any GTE
system modifications for Genuity-specific administrative or program design
changes or software changes.

3.   Employee Opinion Survey (Viewpoints)

     .    Conduct Employee Opinion Surveys on behalf of Genuity utilizing
          current process and program.

     .    Genuity will be administered as part of the main Viewpoints study.

                                                                   Page 5 of 155
<PAGE>

     .    Includes monthly distribution and reporting (approximately 300 per
          month, 3,600 annually)

Pricing Structure:
-----------------

Genuity shall pay GTE as follows:
<TABLE>
<CAPTION>
------------------------------------------------------------------------------------------------
                                   DUE                              COST
------------------------------------------------------------------------------------------------
<S>                                <C>                              <C>
Initial set-up costs               One Time                         $1,000
including questionnaire and
Internet  Survey revisions
------------------------------------------------------------------------------------------------
Basic Study Costs                  Monthly                          $1,200
------------------------------------------------------------------------------------------------
Printing, paper,                   Monthly                          $  150
communication, promotion
------------------------------------------------------------------------------------------------
TOTAL                                                               One Time: $1,000
                                                                    Ongoing/monthly: $1,350
------------------------------------------------------------------------------------------------
</TABLE>

Programming or system work for any employee opinion survey services to be billed
separately at a rate to be mutually agreed upon.

Genuity will be billed separately for actual costs incurred by GTE for any GTE
system modifications for Genuity-specific administrative or program design
changes or software changes.

Genuity's Responsibilities with respect to Other Human Resources Administrative
-------------------------------------------------------------------------------
Services
--------

Genuity understands and agrees that any involvement by GTE with Genuity's other
Human Resources Administrative Services will be in an advisory or consultative
capacity and not in a fiduciary capacity. As between GTE and Genuity, all
             ---
fiduciary responsibility and accountability remains at all times with Genuity.

Genuity will act as the point of contact with all vendors for any matter
relating to fiduciary and plan design issues, with GTE acting merely in an
advisory or consultative capacity.  GTE will act as the point of contact with
all vendors for all other issues.

EMPLOYEE DATA WAREHOUSE DEVELOPMENT AND SUPPORT:

1.  Develop Employee Data Warehouse logical view for Genuity Employees.

    .  Data will be a subset of GTE Employee Data Warehouse data elements

    .  Data will initially consist of SAP current and chronological history only

                                                                   Page 6 of 155
<PAGE>

    .  The data will be a direct extract from source systems and will have
       minimal cleanup

    .  Connectivity via ODBC will be provided to Genuity who will be responsible
       for their own reporting tools

2.  Maintain Employee Data Warehouse View for Genuity and provide Help Desk
    support on an as needed basis.

    .  Provide regular feeds to Genuity Employee Data Warehouse View from SAP

    .  Make minor changes to view data elements and structure

    .  Maintain security profiles and provide access to the Employee Data
       Warehouse

    .  Provide first level help desk support for questions on connectivity

    .  Provide option to Genuity to incorporate new data elements and
       functionality in their Employee Data Warehouse view if and when they do
       become available in the GTE Employee Data Warehouse. The cost will be
       negotiated separately.

    .  Cost does not include training which will be negotiated separately.

                                                                   Page 7 of 155
<PAGE>

Pricing Structure for Employee Data Warehouse Development and Support:
---------------------------------------------------------------------

The pricing quoted below takes into account the work involved in providing the
following services:

Development

Obtain and map required data elements
Create logical data view
Provide load balancing
Test logical data view
User Acceptance Testing (UAT)
Assign security profiles and give users access to view
Provide ODBC connectivity

Annual Support

First level help desk for questions on connectivity
Periodic refresh of view (Periodicity TBD)
Backup and Recovery support
Add new authorized user to view
Add new security Profiles
<TABLE>
<CAPTION>
----------------------------------------------------------------------------------------------
                  Item                           Cost Category              Total Price
----------------------------------------------------------------------------------------------
<S>                                              <C>                        <C>

 .  Annual Support Costs ($3,383/month)             RECURRING
                                                   (ANNUAL)                  $40,590
----------------------------------------------------------------------------------------------

 .  Development
                                                   ONE TIME                  $16,667
----------------------------------------------------------------------------------------------

 .  Total Price - first year                                                  $57,257
----------------------------------------------------------------------------------------------
</TABLE>

Genuity will pay an additional amount to be negotiated separately if it needs
any data element not in the current GTE Employee Data Warehouse or additional
functionality not outlined in the current document.

HR.GTE.COM:

For the purposes of this document, "HR.GTE.COM" is comprised of, and limited to
the following:  Intranet Website shell with design, navigation, and Icons, for
page levels zero and one.

                                                                   Page 8 of 155
<PAGE>

Assumptions:
1.  No outerface links will be provided under this SOW.
2.  No specific content will be included under this SOW. Note: All hr.gte.com
    content is deemed to be GTE proprietary and will not be covered by this SOW.
3.  This SOW includes a one -time copy of existing homepage and level one page
    structures only.
4.  Education & Training and Career Development and Training (CDAT) content and
    functionality are not covered under this SOW.  This can be explored with and
    provided by Jim Roach.
5.  No other specific services will be provided by GTE in the areas of
    HR.GTE.COM Operations or Support.

Pricing Structure for HR.GTE.COM:
--------------------------------

GTE Prices:  All prices associated with this SOW are based on the number of
hours to create and deliver a shell version of hr.gte.com.

Pricing Structure:  Genuity shall pay the following one-time costs:

<TABLE>
<CAPTION>

---------------------------------------------------------------------------------------------
                  Item                       Cost Category             Total Price
---------------------------------------------------------------------------------------------
<S>                                          <C>                       <C>
 .  Initial Setup Level Zero through One
   pages of hr.gte.com production site
 .  Place shell on separate environment       ONE TIME                        $2,837
   and quality assure product
 .  Package product for shipment
---------------------------------------------------------------------------------------------

 .  Total Price                                                               $2,837
---------------------------------------------------------------------------------------------
</TABLE>

HEALTH & WELFARE FUNDING SERVICES:

1.   Provide administrative support to Genuity for employee Benefit Finance
     Information System (BFIS).

     .   Input continually updated enrollment information into BFIS.

     .   Calculate monthly premiums to be paid to trust/custodial account.

     .   Calculate amounts paid by trust/custodial account to vendors.

     .   Monitor claims paid by custodial account to self-insured vendors and
         report activity to Genuity.

     .   Advise self-insured vendors of administrative expense amounts generated
         by the self-bill process.

                                                                   Page 9 of 155
<PAGE>

     .   Maintain BFIS internal tables consistent with Genuity plan design.

     .   Provide management reports to maintain health care plan performance.

     .   Provide report of year-end claims outstanding.

2.   Provide administrative support to Genuity with regard to its health and
     welfare trust or custodial account.

     .   Calculate monthly payments to and from trust/custodian.

     .   Execute payments from trust/custodian.

     .   Reconcile trust activity between Genuity and the trustee/custodian.

3.   Provide Genuity with benefit accounting guidance, cost analysis, and
     funding strategies.

     .   Estimate annual cost and funding based on plan design and past
         experience (to be used for budget and strategic plan projections).

     .   Estimate annual cash commitments.

4.   Provide Genuity with financial analysis for employee benefit plan financial
     analysis.

     .   Provide historical data from BFIS database to support benefit plan
         financial analysis.

5.  Oversee the completion of annual governmental reporting obligations.

     .   Prepare Form 5500 (Annual Report) for all ERISA-governed employee
         benefit plans required to file Form 5500 each year.

     .   Prepare Summary Annual Reports (SARs) as required.

     .   Prepare Form 990 as required.

Genuity's Responsibilities with respect to Health & Welfare Funding Services
----------------------------------------------------------------------------

Genuity understands and agrees that any involvement by GTE with Genuity's
employee benefit plans will be in an advisory or consultative capacity and not
                                                                           ---
in a fiduciary capacity.  As between GTE and Genuity, all fiduciary
responsibility and accountability remains at all times with Genuity.

Genuity shall provide all information/instruction regarding its employees,
employee benefit plans, and vendors as GTE may require to fulfill its
obligations.

                                                                  Page 10 of 155
<PAGE>

Genuity understands and agrees that any proposed changes to plan design or
vendor choice must be compatible with BFIS.

Pricing Structure for Health & Welfare Funding Services
-------------------------------------------------------
<TABLE>
<CAPTION>
---------------------------------------------------------------------------------------------
                 Item                          Cost Category                 Amount
---------------------------------------------------------------------------------------------
<S>                                             <C>                           <C>

 .  Health & Welfare Benefits Funding             RECURRING
   Annual Charge                                                              $40,500
---------------------------------------------------------------------------------------------

 .  Initial Set Up Costs to Establish
   Genuity as a Separate Entity                  ONE TIME                     $20,500

---------------------------------------------------------------------------------------------
 .  Total                                                                      $61,000
---------------------------------------------------------------------------------------------
</TABLE>

Genuity will pay an additional amount to be negotiated separately if GTE cannot
use BFIS to complete its obligations or if any third parties do not continue to
perform their current duties or if additional vendor charges (e.g., software
usage) are imposed upon GTE.

QUINCY PROCESSING CENTER - BENEFITS DELIVERY SYSTEM

For the purposes of this SOW, Benefits Delivery System represents the system
that interfaces with the GTE Payroll systems and the benefit plan vendors as
listed below.

                                                                  Page 11 of 155
<PAGE>

SERVICES
---------

1.  Reconcile and control interfaces from GTE SAP Payroll system
2.  Authorize funds transfers to benefit vendors.
3.  Edit and post data to the Benefits Delivery System Data Base.
4.  Process manual payments and adjustments.
5.  Create outerfaces to vendors based on their specific data requirements, file
    formats, and timing requirements.

       Fidelity Investments
       KVI
       MetLife
       Smith Barney
       Federal  & State Political Action Committee (PAC)
       Hewitt Associates
       AYCO
       TALX
       CORE
       Cendant
       Arthur Andersen
       Edcor
       Other vendors to be mutually agreed upon

6.  Receive and process interface from vendors to GTE Payrolls.

ASSUMPTIONS
-----------

 .  There will be no physical separation of data on the QPC Benefits Delivery
   System (BDS).
 .  Assume no vendor changes.
 .  Assume that Flexible Benefit dollars (GUL, PLP/LTC, FRP, PAC) for Genuity can
   be co-mingled with GTE Flex Ben $ on one interface to the vendors. If a
   separate interface is required to vendors for Genuity information and
   dollars, then a new development SOW would be required.
 .  Assume a separate reconciliation for Genuity.
 .  Assume that the QPC may potentially submit subsequent SOWs as details of the
   Genuity benefits become more defined. At that time, we will evaluate what
   additional time and costs will be necessary in order to provide the agreed
   upon services.

                                                                  Page 12 of 155
<PAGE>

Pricing:
--------

<TABLE>
<CAPTION>
---------------------------------------------------------------------------------------------
                 Item                          Cost Category              Total Price
---------------------------------------------------------------------------------------------
<S>                                             <C>                       <C>
 .  Benefit Delivery System Operations
   ($88,883/month)                               RECURRING                $1,066,594

---------------------------------------------------------------------------------------------

 .  Total Price (Annual)                                                   $1,066,594
---------------------------------------------------------------------------------------------
</TABLE>

QUINCY PROCESSING CENTER:  PENSTAR INTERFACE SYSTEM (INTERFACE TO GTE'S
PENSION CALCULATION SYSTEM AT HEWITT)

SERVICES:

None

ASSUMPTIONS
-----------

The QPC will not track hours and earnings for the Genuity employees.
Hewitt will flag the employees that are due future GTE Pensions.

COSTS
-----

None

QUINCY PROCESSING CENTER - PENSION PAYROLL SYSTEM:

Services
--------

None

ASSUMPTIONS
-----------

No retirees transfer to Genuity and there are no new retirees.

COSTS
-----

None

                                                                  Page 13 of 155
<PAGE>

GENERAL ASSUMPTIONS

General SOW Assumptions/Provisions for Employee Data Warehouse Development and
Support, HR.GTE.COM, Quincy Processing Center--Benefits Delivery System, Quincy
Processing Center: Penstar Interface System (Interface To Gte's Pension
Calculation System At Hewitt), and Quincy Processing Center--Pension Payroll
System:

1.   The HR/Payroll tasks are outlined in several SOWs. HR Technology and
     Information Services tasks in support of non-SAP systems are outlined
     within this SOW. HR Technology and Information Services tasks in support of
     the SAP System are covered under the SAP SOW. Payroll Service Center (PSC)
     tasks are outlined in Finance Functional SOW.

2.   The HR SOWs assume that all services performed for Genuity will continue in
     a similar manner as performed today unless otherwise noted. Only those
     tasks outlined within this SOW shall be performed. Any tasks not outlined
     within this SOW would require a contractual direction from the GTE Account
     Manager.

3.   (GTE Account Manager) is the Genuity point of contact for all contractual
     matters related to this SOW. Any requests for any changes to tasks or new
     functionality should be forwarded in writing to (GTE Account Manager).

4.   The estimates outlined in this SOW assume support for 3,800 Genuity
     employees. If this number increases, the resources assigned to support
     Genuity would need to be reassessed.

5.   It is expected that there will be several changes to the work outlined
     within these SOWs over the next several weeks as benefit plans and other
     specific Genuity processes become finalized. A key point to remember is
     that these types of changes cannot be implemented overnight.

6.   Maintenance tasks within this SOW are for minor Business As Usual (BAU)
     tasks in support of production. If there are any BAU changes/modifications
     beyond minor maintenance, such as mass re-organizations, benefit plan
     changes, new functionality, etc., these changes/modifications will be
     incorporated into a new development SOW. Specific tasks, prices and
     schedules would be developed for the agreed upon SOW.

7.   Genuity agrees to review HR audit reports and act upon any errors
     identified in a timely manner to ensure data integrity within the system
     and with downstream vendors.

8.   Upgrades/Enhancements: For any systems where a common development
     environment exists, e.g., SAP, Employee Data Warehouse (EDW), Quincy
     Processing Center (QPC) systems, agrees to abide by the standards, changes,
     upgrades, and enhancements that have been, or will be, developed and

                                                                  Page 14 of 155
<PAGE>

     implemented across the environment. A proportion of the on-going
     development tasks will be apportioned to Genuity in the same manner as
     production costs as allocated. Examples include Employee Self Service (ESS)
     enhancements, Manager's Desktop, On-line Org Charts. Genuity will
     participate in a user forum to assist in prioritizing these enhancements.

     Should Genuity desire to not abide by, and share appropriate costs for, the
     baseline system configuration and associated upgrades and enhancements, a
     completely separate physical environment for Genuity would be warranted.
     GTE would be pleased to develop a technical and cost proposal for such work
     at the request of Genuity.

9.   This SOW highlights both production tasks and one-time development tasks
     that must also be performed to set up or establish the systems environment
     for Genuity.

     GTE SERVICE CORPORATION                  GENUITY SOLUTIONS INC.

By:___________________________            By:___________________________

Title:________________________            Title:________________________

                                                                  Page 15 of 155
<PAGE>

                                                                    ATTACHMENT 3

                               STATEMENT OF WORK
                               -----------------

                          REAL ESTATE RELATED SERVICES
                          ----------------------------

This Statement of Work is appended to the Agreement for Transition Services (the
"Agreement") dated ______________, by and between Genuity Solutions Inc.
("Genuity") and GTE Service Corporation ("GTE"), and shall be governed by the
terms and conditions thereof. The services described herein shall be provided
for a period of three (3) consecutive months after the Effective Date of the
Transition Services Agreement.

The purpose of this SOW is to provide for the transition of a variety of real
estate related services. The services as described in this SOW relate to real
estate project management, real estate administration, various building services
(including dispatch center services for building-related work requests, building
maintenance services for POP sites, and invoice processing services for invoices
associated with building-related work requests), environmental and safety
services, and building security services. Genuity desires to retain GTE to
provide these services during a transitional period while Genuity hires
necessary staff, implements necessary processes and procedures, and enters into
necessary third party contracts in order to permit the smooth operation of its
business until Genuity is better prepared to handle these services independently
of GTE. None of the services set forth in this SOW are expected to continue for
longer than the initial one-year term of the Agreement.

                    REAL ESTATE PROJECT MANAGEMENT SERVICES

GTE Corporate Real Estate provides project management services for major real
estate projects, including strategic planning, design and construction
management, and accounting project control. Genuity desires to retain GTE to
provide these services as needed and requested by Genuity through written
project authorizations. Any project authorization may be terminated by either
party on 30 days written notice as set forth below.

1.   GTE shall provide real estate project management services for major real
     estate projects, as requested and ordered by Genuity through a written
     project authorization, which shall be subject to GTE's written acceptance
     and approval. Project types may include new leases, lease renewals,
     acquisitions by fee, relocations, build-to-suits and any other project
     involving real estate services. Project management services include:

     .    Evaluate project alternatives to determine cost-effective real estate
          strategies.
     .    Negotiate with outside real estate brokers and developers with respect
          to acquisitions and/or dispositions of real property.
     .    Develop total project budgets.
     .    Coordinate the work of Genuity's outside consultants, including but
          not limited to attorneys and environmental consultants.
     .    Manage the overall real estate project.

2.   GTE shall provide design and construction management services for major
     real estate projects, as requested and ordered by Genuity through a written
     project authorization, which shall be subject to GTE's written acceptance
     and approval. Project types may

                                 Page 1 of 22
<PAGE>

     include build-to-suits and any other project involving design and
     construction of real estate improvements. Design and construction
     management services include:

     .    Review Genuity's initial project assumptions and development of
          preliminary cost estimates, preliminary project programming, and
          preliminary schedule.
     .    Identify, evaluate and recommend outside project consultants.
     .    Coordinate and track the progress of overall design development and
          construction document preparation process.
     .    Manage value engineering process.
     .    Conduct construction management activities.
     .    Coordinate the work of outside design and construction consultants,
          including architects and engineers.
     .    Track and update budgets and schedules.
     .    Manage project closeout activities.

3.   GTE shall provide project control services for major real estate projects,
     as requested and ordered by Genuity through a written project
     authorization, which shall be subject to GTE's written acceptance and
     approval. Project control services include:

     .    Provide accounting project management support on all phases of a
          project plan, design, construction and closeout.
     .    Issue control guidelines and ensure that project commitments and
          expenditures are properly tracked against approved budgets.
     .    Create and update project's financial forecast (outlook).
     .    Prepare and issue a weekly project outlook to the project team.
     .    Review the project for compliance against accepted control practices
          and issue an exception report.
     .    Process approvals for contractor, developer, architect and other
          vendor change requests and reconcile approved change requests to the
          change request log and project outlook.
     .    Audit construction and professional fee invoices to ensure compliance
          to contracts, project control guidelines, and generally accepted
          accounting principles.

4.   Service Commitment. GTE shall follow all Genuity processes and procedures
     that are communicated to GTE.

Genuity's Responsibilities with respect to Real Estate Project Management
-------------------------------------------------------------------------
Services
--------

Genuity shall prepare and submit a project authorization for any real estate
project management services requested under this SOW. The project authorization
shall include a description of the project and a description of any specific
services required by Genuity as part of the project management services. In
addition, Genuity shall provide project support staff as necessary to assist in
the coordination of IT, furniture and move requirements.

Pricing Structure with respect to Real Estate Project Management Services
-------------------------------------------------------------------------

GTE may use GTE-approved subcontractors to provide any of the real estate
project management services under this SOW, with supervision of such
subcontractors to be provided by GTE. During the initial one-year term of the
agreement, Genuity shall pay GTE the following fees for these services:

                                 Page 2 of 22
<PAGE>

          GTE Project Director               $145 per hour
          GTE Project Manager                $135 per hour
          GTE Project Controller             $115 per hour
          GTE Project Accountant             $ 70 per hour
          Subcontractors                     direct cost

In addition to these fees and charges, Genuity shall reimburse GTE for (i) all
travel-related costs and expenses in accordance with the terms of the agreement,
(ii) all costs and expenses for long distance, communications, reproductions,
courier and delivery services, and postage incurred by GTE in the performance of
these services, and (iii) all costs and expenses of consultants or other 3/rd/
party services retained for or on behalf of Genuity in connection with the
performance of real estate project management services, such as appraisals,
surveys and marketing materials. GTE shall submit monthly invoices to Genuity
for the real estate project management services.

Other Specific Terms or Conditions with respect to Real Estate Project
----------------------------------------------------------------------
Management Services
-------------------

GTE may use GTE-approved subcontractors to perform any of the real estate
project management services under this SOW.

Real estate project management services may be ordered by Genuity only through a
written project authorization. All project authorizations shall be subject to
GTE's written acceptance and approval.

Any project authorization may be terminated by either party for any or no reason
upon 30 days written notice. In the event of termination, Genuity shall pay GTE
for all services performed through the date of termination.

Notwithstanding the expiration of the term of this SOW, this SOW shall remain in
effect with respect to and for the duration of any project authorization entered
into under this SOW that by its terms extends beyond the expiration of this SOW.

                      REAL ESTATE ADMINISTRATION SERVICES

GTE Corporate Real Estate provides lease administration services, new lease and
lease renewal support, and support for acquisitions and dispositions of owned
real estate. In connection with these services, real estate information is
entered into a GTE-owned real estate database. Genuity desires to use the
GTE-owned real estate database and to retain GTE to provide these services
during a transition period while Genuity builds its own real estate organization
and evaluates the service options available to it from other third party
providers. The real estate administration services may be terminated by Genuity
on 60 days written notice as set forth below.

1.   GTE shall furnish the GTE Real Estate Database for use by GTE, GTE's
     subcontractors and Genuity personnel during the term of this SOW for
     maintenance of Genuity's real estate data. Genuity's use of the GTE Real
     Estate Database is limited to the use described in this SOW and the
     services to be provided by GTE in connection therewith are expressly
     limited to the following:

                                 Page 3 of 22
<PAGE>

     .    Install a duplicate copy of the GTE Real Estate Database (RED),
          transfer to this duplicate database (Duplicate RED) all Genuity
          records residing on RED, and provide access rights to Duplicate RED to
          appropriate GTE personnel and subcontractors.
     .    If and as requested by Genuity, setup additional Genuity users on
          Duplicate RED and train Genuity personnel on use of RED.

     Genuity's rights to use Duplicate RED shall automatically terminate upon
     expiration or termination of this SOW.

2.   GTE shall provide the following real estate lease administration services:

     .    Prepare lease abstract and lease responsibility matrix for all
          executed leases. Lease abstracts shall include property information
          (such as address and square footage), rent stream during entire term,
          escalation clauses, sales tax, critical dates (such as scheduled rent
          increases and renewal options), and other special options and clauses
          (such as expansion rights and rights of first refusal)
     .    Enter lease data in Duplicate RED, including all actions required to
          set up property on Duplicate RED and entry of data from lease
          abstract.
     .    File set-up, including distribution of new lease and/or lease renewal
          notification letters to distribution list identified by Genuity,
          together with copies of lease abstract and lease responsibility
          matrix.
     .    Coordinate insurance, including communication with insurance contacts
          as identified and directed by Genuity to secure certificates of
          insurance and follow-up with landlords to insure receipt.
     .    Complete and process payment forms as identified and directed by
          Genuity.
     .    Critical date reporting, as well as on-going review of, and initiation
          of actions identified on critical date reports.
     .    Operating expense true-ups, including review of landlords' operating
          expense reconciliations to confirm consistency and compliance with
          lease terms, including accuracy of landlords' computations.
     .    Process estoppel certificates and non-disturbance, subordination and
          attornment agreements, including review and confirmation of lease
          terms and coordination of legal review by Genuity's designated legal
          counsel.
     .    "Lease-To" administration, including preparation of forms for billing
          tenants and subtenants for all leases-to's and subleases, notification
          of rent payment adjustments, processing insurance certificates, and
          abstracting new leases.
     .    Process standard reports from information resident in Duplicate RED.
     .    Budget support, such as provision of current rent information with
          projected base rent increases and estimated operating expense
          adjustments.
     .    Administer landlord/tenant communications, including escalation point
          of contact with landlords on maintenance issues and follow-up with
          Genuity and preparation of letters to landlords to communicate address
          or reporting changes.

3.   GTE shall provide new lease and complex lease renewal administrative
     support, specifically:

     .    Database input, including entry of request/assignment in Duplicate RED
          and coordination of responsibilities concerning the new lease or
          complex renewal.
     .    On-going coordination and communication among all responsible persons.

                                 Page 4 of 22
<PAGE>

     .    Coordinate and process internal approval documentation based on
          approval matrix submitted by Genuity and as otherwise identified and
          directed by Genuity, such as preparation of financial analyses and
          Genuity requisition forms, comparison of business case information
          with financial analyses to conform to Genuity requirements, and
          tracking of internal approval documents until fully executed.
     .    Lease document review and preparation of proposed revisions and
          comments.
     .    Coordinate legal review by Genuity's designated legal counsel.
          Submit approved lease documentation for execution.
     .    Weekly review of all current files, participation in project meetings
          for communication with Genuity team, and preparation of any
          correspondence or additional documents to resolve special issues.

4.   GTE shall provide administrative support for simple lease renewals,
     specifically:

     .    Coordinate and process internal approval documentation based on
          approval matrix submitted by Genuity and as otherwise identified and
          directed by Genuity.
     .    Review of lease document for terms and conditions of renewal.
     .    Prepare notification letters to landlords.
     .    Communicate with individuals designated by Genuity to ensure that rent
          payments are current during the renewal phase.
     .    Coordinate legal review by Genuity's designated legal counsel.
     .    Submit approved documentation for execution.

5.   GTE shall provide administrative support for "lease-to's" (both affiliate
     and non-affiliate transactions), specifically:

     .    Receive and review initial request from prospective tenant, and
          coordinate completion of any requisite internal approval forms based
          on approval matrix submitted by Genuity and as otherwise identified
          and directed by Genuity.
     .    Determine fair market value for lease rate.
     .    Coordinate and process any internal approvals as identified and
          directed by Genuity.
     .    Respond to questions and requests and participate in meetings as
          necessary.
     .    Prepare lease document and coordinate legal review and approval by
          Genuity's designated legal counsel.
     .    Circulate approved lease documents for execution.

6.   GTE shall provide administrative support for real property acquisitions,
     specifically:

     .    Database input, including entry of request/assignment in Duplicate RED
          and coordination of responsibilities concerning the acquisition, as
          well as on-going entry of updates on progress of site selection.
     .    Distribute information about prospective sites to individuals
          designated by Genuity.
     .    Prepare, submit and route any concurrence memoranda to various Genuity
          departments and/or individuals as identified and directed by Genuity
          (such as Environmental Affairs, Building Services and Network
          Construction).
     .    Order appraisals and brokers' opinions of value as directed by
          Genuity.
     .    Order title search and a survey and route to appropriate individuals
          as identified and designated by Genuity.
     .    Coordinate and process internal approval documentation based on
          approval matrix submitted by Genuity and as otherwise identified and
          directed by Genuity, such as

                                 Page 5 of 22
<PAGE>

          preparation of financial analyses and Genuity requisition forms,
          comparison of business case information with financial analyses to
          conform to Genuity requirements, and tracking of internal approval
          documents until fully executed.
     .    Coordinate preparation of purchase contract, review purchase contract
          and prepare proposed revisions and comments, and coordinate legal
          review by Genuity's designated legal counsel.
     .    Submit approved purchase contract for execution by Genuity.
     .    Post-closing, prepare log of all charges associated with acquisition
          of property.
     .    Notify individuals designated by Genuity of the property acquisition
          and distribute copies of relevant closing documents as directed by
          Genuity.
     .    Participate in project meetings for communication with Genuity team,
          prepare any correspondence or additional documents to resolve special
          issues, and route invoices for payment.

7.   GTE shall provide administrative support for disposition of owned real
     estate, specifically:

     .    Research inquiries from interested parties.
     .    Prepare, submit and track any concurrence memoranda to various Genuity
          departments and/or individuals as identified and directed by Genuity.
     .    Prepare summary of responses to concurrence memoranda and submit to
          Genuity for further direction.
     .    If Genuity declares property to be surplus, coordinate disposition.
          Obtain appraisal or broker's opinion of value; compile property
          information file and obtain any documents or information not received
          during research phase; present information to Genuity for
          determination of sales price; and handle and coordinate negotiations
          with prospective buyer.
     .    Market property.
     .    Coordinate and process internal approval documentation based on
          approval matrix submitted by Genuity and as otherwise identified and
          directed by Genuity, such as preparation of financial analyses and
          Genuity requisition forms, comparison of business case information
          with financial analyses to conform to Genuity requirements, and
          tracking of internal approval documents until fully executed.
     .    Coordinate preparation of sales contract, review sales contract and
          prepare proposed revisions and comments, and coordinate legal review
          by Genuity's designated legal counsel.
     .    Submit approved sales contract for execution by Genuity.
     .    Notify individuals designated by Genuity of the property disposition
          and distribute copies of relevant closing documents as directed by
          Genuity.
     .    Post-closing, prepare log of all charges associated with marketing and
          sale of property.
     .    Participate in project meetings for communication with Genuity team,
          prepare any correspondence or additional documents to resolve special
          issues, and route invoices for payment.
     .    Maintain Genuity owned real estate information in Duplicate RED.

8.   Service Commitment. GTE shall follow all Genuity processes and procedures
     that are communicated to GTE.

Genuity's Responsibilities with respect to Real Estate Administration Services
------------------------------------------------------------------------------

                                 Page 6 of 22
<PAGE>

Genuity shall provide all information required for GTE to perform its duties
hereunder.

Pricing Structure with respect to Real Estate Administration Services
---------------------------------------------------------------------

GTE may use GTE-approved subcontractors to provide any of the real estate
administration services under this SOW, with supervision of such subcontractors
to be provided by GTE. During the initial one-year term of the agreement,
Genuity shall pay GTE the following fees for these services:

          Annual Administrative Fee:     $110,000.00, payable in equal
                                         monthly installments of $9,166.67; this
                                         administrative fee covers all travel,
                                         general office expenses and other
                                         overhead

          Subcontractors:                direct cost for all services obtained
                                         from subcontractors, including without
                                         limitation all costs associated with
                                         installation and administration of
                                         Duplicate RED and all transaction fees
                                         payable in connection with brokerage
                                         services, EXCEPT for any administrative
                                         fee payable by GTE to Cushman &
                                         Wakefield, Inc. and/or The Staubach
                                         Company and/or any subcontractor
                                         providing similar administrative
                                         services.

GTE estimates that the subcontractor fees associated with installation of
Duplicate RED will be approximately $13,000.00, plus approximately $400.00 for
each additional user designated by Genuity.

In addition to these fees and charges, Genuity shall reimburse GTE for all costs
and expenses of consultants or other 3rd party services retained for or on
behalf of Genuity in connection with the performance of real estate
administration services, such as appraisals, surveys and marketing materials.
GTE shall submit monthly invoices to Genuity for the real estate administration
services.

Other Specific Terms or Conditions with respect to Real Estate Administration
-----------------------------------------------------------------------------
Services
--------

GTE may use GTE-approved subcontractors to perform any of the real estate
administration services under this SOW. Without limiting the generality of the
foregoing, Genuity acknowledges and agrees that GTE may subcontract any or all
of the real estate administration services to Cushman & Wakefield, Inc. and The
Staubach Company and their respective affiliates.

Genuity may terminate the real estate administration services set forth herein
for any or no reason upon 60 days written notice. In the event of such
termination, Genuity shall pay GTE for all services performed through the date
of termination.

                           DISPATCH CENTER SERVICES

GTE Support Assets provides a 24-hour call center for entry and dispatching of
work requests for certain building services. Genuity desires to retain GTE to
provide these services during a

                                 Page 7 of 22
<PAGE>

transition period while Genuity makes alternate arrangements for these services.
GTE has agreed to provide these services through December 31, 2000; however,
Genuity may terminate these services at any time as set forth below.

1.   GTE shall provide 24-hour call center and dispatch function for building
     operation, maintenance and repair and for furniture repairs and
     rearrangements. Work will be dispatched to the employee or contractor
     designated by Genuity.

2.   Service Commitment. GTE will dispatch each work request within 10 minutes
     of receiving the call.

Term for Dispatch Center Services
---------------------------------

GTE shall provide these dispatch center services through December 31, 2000,
subject to termination of these services by Genuity at any time in its sole and
absolute discretion.

Genuity's Responsibilities with respect to Dispatch Center Services
-------------------------------------------------------------------

Genuity shall provide all information required for GTE to perform its duties
hereunder including, but not limited to, (a) the names and contact information
for all employees and contractors designated by Genuity to receive work requests
for (i) building operation, maintenance and repairs and (ii) furniture repairs
and rearrangements, and (b) location, contact information, and the nature of
services required for each work request.

Pricing Structure for Dispatch Center Services
----------------------------------------------

Genuity shall pay GTE at a rate of $9.70 per work request. GTE shall submit
quarterly invoices to Genuity for these dispatch center services.

Other Specific Terms or Conditions with respect to Dispatch Center Services
---------------------------------------------------------------------------

The parties understand and agree that GTE may cause these dispatch center
services to be provided by or through one of its Network Services affiliates.

                     POP SITE BUILDING TECHNICIAN SERVICES

GTE Support Assets manages building technicians who provide building maintenance
and repair services to certain points of presence (POP sites) on Genuity's fiber
optic network. Genuity desires to retain GTE to provide these building
maintenance and repair services during a transition period to allow Genuity to
make alternate arrangements for these services. GTE has agreed to provide these
services through December 31, 2000; however, Genuity may terminate these
services at any time as set forth below.

1.   GTE shall provide building repairs and maintenance for (number) currently
     existing Genuity POP sites as requested by Genuity. Maintenance shall
     include preventative maintenance as well as maintenance and repairs
     necessitated by equipment failure. No new POP sites will be added to the
     number of POP sites covered by this agreement.

                                 Page 8 of 22
<PAGE>

2.   GTE is hereby authorized to purchase parts and materials up to $500.00 per
     work request in connection with the performance of these services without
     any other or further authorization from Genuity. GTE shall not purchase any
     parts or materials in excess of $500 per work authorization without prior
     authorization from Genuity.

3.   Service Commitment. Building technicians will respond within the following
     time frames:

          Emergency (Priority 1) - within 24 hours
          Non-emergency (Priority 3) - within 7 days

Term for POP Site Building Technician Services
----------------------------------------------

GTE shall provide these POP site building technician services through December
31, 2000, subject to termination of these services by Genuity at any time in its
sole and absolute discretion.

Genuity's Responsibilities with respect to POP Site Building Technician Services
--------------------------------------------------------------------------------

Genuity shall provide all information required for GTE to perform its duties
hereunder. In addition, Genuity shall provide access to all sites, and contact
information for an Genuity contact with whom to discuss problem resolution.

Pricing Structure with respect to POP Site Building Technician Services
-----------------------------------------------------------------------

Genuity shall pay GTE at a rate of $34.32 per hour for these services, including
travel time. In addition to the hourly fees, Genuity shall reimburse GTE for all
travel-related costs and expenses and the cost of all parts and materials used
by GTE and/or the building technicians in the performance of these services, all
in accordance with the terms of the agreement and this SOW. GTE shall submit
quarterly invoices to Genuity for these POP site building technician services.

Other Specific Terms or Conditions with respect to POP Site Building Technician
-------------------------------------------------------------------------------
Services
--------

GTE may use GTE-approved subcontractors to perform the POP site building
technician services described in this SOW. Without limiting the generality of
the foregoing, the parties further understand and agree that GTE may cause these
building technician services to be provided by or through one of its Network
Services affiliates.

                        FM INVOICE PROCESSING SERVICES

GTE Support Assets provides invoice processing services for invoices associated
with work requests generated by the call center and entered into its FM system.
Genuity desires to retain GTE to provide these invoice processing services
during a transition period to allow Genuity to make alternate arrangements for
these services. GTE has agreed to provide these services for all invoices
associated with a FM invoice through December 31, 2000; however, Genuity may
terminate these services at any time as set forth below.

1.   GTE shall perform all invoice processing of all Genuity invoices for
     building and furniture-related work associated with a FM work request. GTE
     shall receive, review and

                                 Page 9 of 22
<PAGE>

     electronically process these invoices for approval and payment though the
     FM system and the GTE accounts payable system.

2.   Service Commitment. GTE shall process each invoice within three business
     days of receipt.

Term for FM Invoice Processing Services
---------------------------------------

GTE shall provide these FM invoice processing services through December 31,
2000, subject to termination of these services by Genuity at any time in its
sole and absolute discretion.

Genuity's Responsibilities with respect to FM Invoice Processing Services
-------------------------------------------------------------------------

Genuity shall provide all information/instruction regarding processing and
payment of invoices.

Pricing Structure with respect to FM Invoice Processing Services
----------------------------------------------------------------

Genuity shall pay GTE $4.28 per invoice for these services. GTE shall submit
quarterly invoices to Genuity for these invoice processing services.

Other Specific Terms or Conditions with respect to FM Invoice Processing
------------------------------------------------------------------------
Services
--------

GTE shall provide these services only for invoices related to a work request
generated from the FM system. The parties understand and agree that GTE may
cause these FM invoice processing services to be provided by or through one of
its Network Services affiliates.

                      ENVIRONMENTAL SERVICES - IN GENERAL

GTE Environmental Affairs provides a variety of environmental services,
including environmental investigation and inspection services in connection with
real estate transactions, environmental compliance services, and environmental
administration and project management. Genuity desires to retain GTE to provide
these environmental services during a transition period to allow Genuity to make
alternate arrangements for these services. GTE has agreed to provide
environmental real estate transaction services for all proposed POP sites and
for other sites as requested by Genuity, environmental compliance services as
needed and requested by Genuity, and environmental administration and project
management services. Genuity may terminate these services upon 60 days written
notice as set forth below.

                ENVIRONMENTAL REAL ESTATE TRANSACTION SERVICES

1.   Upon request by Genuity, GTE shall conduct a Step 1 Phase I. A Step I Phase
     I is a site assessment with a limited scope that may be appropriate for
     certain property transactions, for example a lease of office space where no
     hazardous chemicals are used or stored. GTE may perform these assessments
     or, depending on the location of the property and time constraints, a GTE
     may retain a 3/rd/ party consultant to perform these assessments on behalf
     of Genuity. Upon completion of the Step I Phase I GTE shall deliver to
     Genuity either an E-mail or letter report outlining the issues found at the
     site and any recommendations for additional work.

                                 Page 10 of 22
<PAGE>

2.   GTE shall conduct a Phase I site assessment on all properties Genuity
     proposes to use as a POP site and on other properties as requested by
     Genuity. GTE shall retain 3/rd/ party consultants to perform these
     assessments. The Phase I site assessments shall be conducted as per
     American Society for Testing and Materials (ASTM) standards, and shall
     include a detailed history of the condition of the property and surrounding
     properties, as well as data base searches to see if the site has ever been
     listed with any of the Federal, State or local agencies. In addition, the
     Phase I site assessment also determines if any types of hazards exist at
     the site, either from past spills/releases or potential releases. GTE shall
     deliver a preliminary E-mail report outlining the issues found at the site
     and any recommendations for addition work, as well as a formal written
     Phase I report from the 3/rd/ party consultant.

3.   Based upon GTE's recommendations and upon request by Genuity, GTE shall
     conduct a Phase II site assessment on properties at which a Phase I site
     assessment already has been completed and at which issues have been raised
     about possible contamination. GTE shall retain 3/rd/ party consultants to
     perform these assessments. A Phase II site assessment typically includes
     removal of samples and testing, such as soil samples and ground water
     testing. GTE shall propose the scope of the Phase 2 site assessment, which
     shall be subject to review and approval by Genuity. GTE shall deliver a
     preliminary E-mail report outlining the lab results and any recommendations
     for additional work, as well as a formal written Phase II letter report
     from the 3/rd/ party consultant.

4.   Based upon GTE's recommendations and upon request by Genuity, GTE shall
     conduct an Asbestos and Lead Survey on properties that are expected to
     undergo construction renovations and on all properties being offered for
     sale by Genuity. GTE shall retain a 3/rd/ party consultant to perform the
     Asbestos and Lead Survey. The surveys shall include the sampling of any
     suspect asbestos containing materials (ACM) and any suspect lead painted
     surfaces. GTE shall deliver a preliminary E-mail report outlining the lab
     results from the survey and any recommendations on how to conduct any
     recommended abatement, as well as a formal written ACM/Lead Report from the
     3/rd/ party consultant.

5.   Follow-up Evaluation Remediations -If the environmental site assessment for
     a property transaction reveals some type of contamination which must be
     removed, abated, remediated or cleaned-up ("remediation"), GTE shall manage
     the remediation if requested by Genuity. If Genuity retains GTE to manage
     any remediation project, GTE will identify and evaluate 3/rd/ party
     consultants and remediation contractors, will review all proposals and
     negotiate changes to the proposals, and make recommendations to Genuity on
     the best appropriate course of action.

Genuity's Responsibilities with respect to Environmental Real Estate Transaction
--------------------------------------------------------------------------------
Services
--------

Genuity is responsible for providing all information and data required for GTE
to perform its duties hereunder, including, but not limited to, a detailed list
of all new facilities to be considered for new leases/ownership, including
address, point of contact, and age of building. Genuity also shall provide all
information/instruction regarding processing and payment of invoices and expense
reports.

                       ENVIRONMENTAL COMPLIANCE SERVICES

                                 Page 11 of 22
<PAGE>

1.   SPCC Plans - Upon request by Genuity, GTE shall select and retain
     consultants with a Registered Professional Engineer on staff to prepare
     SPCC Plans for all properties as required by Federal regulations, including
     aboveground tanks with a quantity of 660 gallons or an aggregate of 1,320
     gallons or more of any petroleum product, and any underground storage tank
     with an aggregate of 42,000 gallons. GTE shall select the consultant,
     review the draft plan to determine if any corrections need to be made, and
     review and approval the final plan. GTE shall send a copy of each final
     SPCC Plan to the applicable site supervisor and maintain a copy on file.
     GTE also will determine when SPCC Plans require updates.

2.   SPCC Training - Upon request by Genuity, GTE shall provide an employee
     lesson plan and roster sheet to site supervisors in order to permit Genuity
     to comply with Federal regulations that require the annual training of
     employees who may respond to a spill involving a SPCC regulated tank. GTE
     will maintain a copy of the training roster and will follow-up on any
     rosters not received.

3.   Business Emergency Plans and SARA Title III Reporting - Upon request by
     Genuity, GTE shall review Federal, State and Local regulations relating to
     hazardous materials and complete all mandated reporting to the state-
     administering agencies for SARA Title III reports and state-mandated
     business emergency and other types of plans triggered by certain quantities
     of hazardous materials. GTE shall retain a 3rd party consultant to write
     site-specific business plans as required by the regulations.

4.   Compliance Inspections - Upon request by Genuity, GTE shall perform
     compliance inspections at a designated percentage of reportable facilities.
     GTE shall verify the information submitted to the state agencies, including
     Battery and Fuel Storage data and completion of the eleven-part GTE
     Inspection report. GTE shall submit an inspection report to the site
     supervisor so that the site supervisor may correct any deficiencies found
     during the Inspection.

5.   Spill Kits for Batteries and Fuel Oil Tanks - Upon request by Genuity, GTE
     shall provide spill control equipment as required at Genuity facilities
     that use or store hazardous materials.

6.   Hazardous and Regulated Chemical Wastes - Upon request by Genuity, GTE
     shall manage the disposal of Genuity's Universal Wastes in accordance with
     Federal, State and Local regulations. GTE shall verify applicable disposal
     requirements, select contractors/disposal firms to handle/dispose/recycle
     the wastes, determine if facilities need an EPA ID number, complete all
     applicable paperwork, schedule pickups, and obtain copies of the shipping
     papers for permanent records.

7.   Disposal/Recycling of Batteries - Upon request by Genuity, GTE will arrange
     for the disposal of Genuity's lead-acid batteries if such a need arises
     outside of the terms of Genuity's battery maintenance agreement. GTE shall
     set up a national service agreement for battery disposal. If requested by
     Genuity, GTE shall provide a list of battery recycling facilities and shall
     audit the disposal/recycling facilities. In addition, GTE will check local
     and state regulatory requirements to determine if there are any
     restrictions on battery disposal. GTE will complete and submit all
     applicable notifications/documentation required by regulatory agencies.

                                 Page 12 of 22
<PAGE>

Genuity's Responsibilities with respect to Environmental Compliance Services
----------------------------------------------------------------------------

Genuity is responsible for providing all information and data required for GTE
to perform its duties hereunder including, but not limited to, copies of all
environmental violations or citations, notification of any spill/release of
chemical of concern, hazardous/regulated waste transportation records,
hazardous/regulated waste disposal records, and information about all new
Genuity facilities. For each new Genuity facility, Genuity shall advise GTE if
the facility has any aboveground storage tanks (AST's) or lead-acid batteries,
and if it does the size and contents of the AST's, as well as number,
manufacturer, make and model of lead-acid batteries. Genuity shall provide
access to sites for GTE and GTE's 3rd party contractor personnel as needed and
appropriate to complete reports, inventories, plans and assessments. Genuity
shall provide or confirm chemical inventory information, site contact
information and other data needed to complete reports, plans and inventories.
Genuity shall inform and/or train its employees concerning chemical safety,
emergency contingency procedures and chemical release provisions of written
plans at Genuity sites. Genuity shall inform GTE of facility changes that
trigger a need to revise inventories, business plans, spill plans or contingency
plans. Genuity also shall provide all information/instruction regarding
processing and payment of invoices and expense reports.

                     ENVIRONMENTAL ADMINISTRATION SERVICES

1.   Record Retention - GTE shall administer the paperwork as well as process
     and archive required records in a central system. GTE shall keep Genuity's
     records separate from GTE environmental records. Genuity's records shall be
     the property of Genuity and will be transferred to Genuity, at Genuity's
     expense, as and when directed by Genuity.

2.   Review Reports - In addition to the reports to be reviewed by GTE under
     other provisions of this SOW, GTE will review and provide comments and
     recommendations to Genuity concerning 3rd party consultants' work products
     and reports as requested by Genuity. GTE also will edit, help define and
     make recommendations to Genuity on applicable scopes of work for various
     projects.

3.   Vendor Contracts - Upon request by Genuity, GTE will assist Genuity with
     contract negotiations with various 3rd party environmental consultants.

4.   Review Invoicing - GTE will review all invoices submitted by 3rd parties
     retained by GTE for accuracy and timely billing. GTE shall verify each
     invoice against the original contract proposal and shall process invoices
     in accordance with Genuity instructions to GTE.

Genuity's Responsibilities with respect to Environmental Administrative Services
--------------------------------------------------------------------------------

Genuity is responsible for providing all information and data required for GTE
to perform its duties hereunder including, but not limited to, a list of vendors
with whom Genuity desires to enter into contracts and procedures for record
retention. Genuity also shall provide all information/instruction regarding
processing and payment of invoices and expense reports.

                   ENVIRONMENTAL PROJECT MANAGEMENT SERVICES

                                 Page 13 of 22
<PAGE>

1.   Point of Contact - GTE shall designate a single point of contact to
     administer, monitor and follow-up on all work and program efforts. This
     project manager will provide monthly reports on program and compliance
     status to Genuity management.

2.   Environmental Data Base - GTE shall establish an environmental database for
     GNI environmental work. The database will summarize by facility
     environmental work completed and key environmental characteristics of each
     site.

3.   Reports - GTE shall provide standardized reports and metrics concerning the
     status of environmental programs to Genuity in mutually agreed formats. GTE
     and Genuity shall jointly devise and mutually agree upon reports frequency
     and content.

4.   Invoicing - GTE will submit monthly invoices to Genuity for each month's
     service fee. The invoices will include a break down of labor costs by
     category and a separate line item for each expense category. GTE will
     retain monthly time sheets for each staff member that worked on the Genuity
     program showing their hours and the nature of the work performed. Invoices
     for contractor work and travel expense accounts will also be available by
     month. These backup records are to be maintained for three years. GTE shall
     make supporting documentation available for Genuity's review at GTE's
     offices at any time during normal business hours.

Genuity's Responsibilities with respect to Environmental Project Management
---------------------------------------------------------------------------
Services
--------

Genuity shall provide all information and data required for GTE to perform its
duties hereunder including, but not limited to, providing GTE an Genuity point
of contact to coordinate project management services and data needed to develop
and maintain an environmental database. Genuity also shall provide all
information/instruction regarding processing and payment of invoices and expense
reports.

Pricing Structure for All Environmental Services Described in this SOW
----------------------------------------------------------------------

            Program Administrator                    $76.00 per hour
            Program Manager                          $57.00 per hour
            Administrative                           $31.00 per hour
            Subcontractors and Consultants           direct cost + 10%

In addition to these fees and charges, Genuity shall reimburse GTE for all
travel-related costs and expenses in accordance with the terms of the agreement
and for all costs and expenses for long distance, communications, reproductions,
courier and delivery services, postage and supplies incurred by GTE in the
performance of these services.

Other Specific Terms or Conditions with respect to Environmental Services
-------------------------------------------------------------------------

GTE may use GTE-approved subcontractors to perform any of the environmental
services under this SOW.

Any or all of the Environmental Services described in this SOW may be terminated
by Genuity for any or no reason upon 60 days written notice. In the event of
termination, Genuity shall pay GTE for all services performed through the date
of termination.

                                 Page 14 of 22
<PAGE>

LIMITATIONS WITH RESPECT TO ALL ENVIRONMENTAL SERVICES
------------------------------------------------------

     GTE makes no representation or warranty concerning Genuity's environmental
     compliance; it is not possible for GTE to warrant Genuity's environmental
     compliance. GTE, acting in the capacity of an environmental consultant to
     Genuity, shall perform the environmental services described in this SOW in
     accordance with generally accepted practices in the environmental
     consulting field. Genuity acknowledges and agrees that GTE must, of
     necessity, rely upon information reported by Genuity employees and 3rd
     parties. GTE is not responsible for the accuracy of information provided by
     Genuity or any 3rd party, including without limitation subcontractors and
     consultants retained by GTE. Although this SOW states that GTE shall
     provide a variety of reports, the parties understand and agree that GTE's
     primary responsibility with respect to reports generated by 3rd parties is
     for GTE to coordinate and review such reports, using that degree of care
     GTE routinely exercises with respect to similar reports for its own
     properties.

     Genuity shall inform GTE of all pertinent details of Genuity properties and
     operations that have environmental implications. Genuity also has
     responsibility to physically maintain its sites and the on-site records
     specified by GTE. Genuity is responsible for ensuring that its on-site
     personnel attend training and refresher reviews of the plans and procedures
     written for their respective sites.

                                 SAFETY SERVICES

GTE Safety provides certain safety management, analysis, inspection and
administrative services. Genuity desires to retain GTE to provide these services
during an interim period while Genuity makes alternate arrangements for these
services. GTE has agreed to provide the identified safety services as needed and
requested by Genuity. Genuity may terminate these services upon 60 days written
notice as set forth below.

1.   GTE shall provide the following safety services upon request of Genuity:

     .   On-site safety management services. Genuity shall provide a single
         point of contact to administer, monitor, and follow-up on program
         activities.
     .   On-site job safety analysis to identify potential hazards and develop
         site specific recommendations for corrective action.
     .   Inspection of Genuity facilities and operations to monitor compliance
         with occupational safety regulations.
     .   Respond to or contest an OSHA citation at the informal hearing level
         and higher.
     .   Identify site-specific safety training requirements, such as defensive
         driving, first aid/CPR, lockout/tagout, hearing conservation, hazard
         communication, emergency evacuation, and ergonomics. GTE may conduct
         this training or coordinate the appropriate training through a third
         party vendor.
     .   Provide local supervision with root-cause investigation support for
         serious injuries or vehicle collisions that result in a loss time
         injury or fatality.
     .   Coordination with a Certified Industrial Hygiene vendor to resolve
         indoor air quality issues in facilities owned or leased by Genuity.

                                 Page 15 of 22
<PAGE>

     .   Assist in the development of building emergency evacuation plans for
         Genuity facilities.

2.   In connection with such safety services, GTE shall provide the following
     safety program administration services:

     .   Record Retention - GTE shall administer the paperwork as well as
         process and archive required records in a central system. GTE shall
         keep Genuity's records separate from GTE safety records. Genuity's
         records shall be the property of Genuity and will be transferred to
         Genuity, at Genuity's expense, as and when directed by Genuity.
     .   Vendor Contracts - Upon request by Genuity, GTE will assist Genuity
         with contract negotiations with various 3rd party consultants. In
         addition, as requested by Genuity, GTE shall monitor Genuity's
         consultants for quality control, cost-effective solutions, timely
         delivery of reports and otherwise to protect the interests of Genuity.
     .   Review Invoicing - GTE will review all invoices submitted by 3rd
         parties retained by GTE for accuracy and timely billing. GTE shall
         verify each invoice against the original contract proposal and shall
         process invoices in accordance with Genuity instructions to GTE.
     .   Standardized Reports - As requested by Genuity, GTE shall provide
         standardized reports concerning the status of safety support activities
         in a mutually agreeable format. Frequency and content of reports to be
         mutually agreed upon.
     .   Invoicing - GTE will submit monthly invoices to Genuity for each
         month's service fee. The invoices will include a break down of labor
         costs by category and a separate line item for each expense category.
         GTE will retain monthly time sheets for each staff member that worked
         on the Genuity program showing their hours and the nature of the work
         performed. Invoices for contractor work and travel expense accounts
         also will be available by month. These backup records are to be
         maintained for three years. GTE shall make supporting documentation
         available for Genuity's review at GTE's offices at any time during
         normal business hours.

Genuity's Responsibilities with respect to Safety Services
----------------------------------------------------------

Genuity shall provide all information required for GTE to perform its duties
hereunder. Genuity must inform GTE of the pertinent details of any of Genuity's
operations that may have employee safety implications.

Pricing Structure with respect to Safety Services
-------------------------------------------------

          Safety Director                    $76.00 per hour
          Safety Specialist                  $57.00 per hour
          Subcontractors and Consultants     direct cost + 10%

In addition to these fees and charges, Genuity shall reimburse GTE for all
travel-related costs and expenses in accordance with the terms of the agreement
and for all costs and expenses for long distance, communications, reproductions,
courier and delivery services, postage and supplies incurred by GTE in the
performance of these services.

Other Specific Terms or Conditions with respect to Safety Services
------------------------------------------------------------------

                                 Page 16 of 22
<PAGE>

GTE may use GTE-approved subcontractors to perform any of the safety services
under this SOW.

Any or all of the safety services described in this SOW may be terminated by
Genuity for any or no reason upon 60 days written notice. In the event of
termination, Genuity shall pay GTE for all services performed through the date
of termination.

LIMITATIONS WITH RESPECT TO SAFETY SERVICES
-------------------------------------------

     The purpose of this SOW with respect to safety services is to assist
     Genuity in fulfilling its responsibility to establish and maintain a safe
     work environment for employees. GTE does not (and cannot) warranty
     Genuity's occupational safety compliance and does not assume any of
     Genuity's safety responsibilities. Genuity must maintain its work place
     free from recognized hazards in accordance with OSHA regulations, ensure a
     safe environment for its employees, and take such steps as are necessary
     and appropriate to prevent accidents or losses.

     Genuity shall inform GTE of all pertinent details of Genuity properties and
     operations that have safety implications. Genuity also has responsibility
     to physically maintain its sites and the on-site records specified by GTE.

                    IRVING-BASED BUILDING SECURITY SERVICES

GTE Security provides ID badge and card key issuance, alarm monitoring and
investigative services for certain Genuity buildings in the Irving, Texas area.
Genuity desires to retain GTE to provide these services during a transition
period while Genuity makes alternate arrangements for these services. Genuity
may terminate these services upon 60 days written notice as set forth below.

1.   GTE shall issue ID badges and/or keycards to Genuity employees upon request
     and approval by an authorized Genuity supervisor. Genuity shall submit the
     ID badge and/or keycard request on a request form approved for use by GTE's
     Employee & Asset Protection department.

2.   GTE will provide 24 hour monitoring of alarms in accordance with current
     practices and procedures in Genuity's buildings in Irving, TX and at which
     GTE currently provides these services. GTE will provide notification of
     alarms to Genuity in accordance with instructions from Genuity. Genuity
     understands and agrees that GTE's sole responsibility under this paragraph
     is to monitor the alarms and give notice of alarms in accordance with
     instructions from Genuity. GTE has no obligations or responsibilities to
     provide any other response to alarms.

3.   Upon request of Genuity, GTE shall perform investigative services for
     Genuity to facilitate fact finding and improve information gathering in
     support of Genuity senior management, as well as to aid in prosecutorial
     activities, facilitate recoveries and encourage loss prevention. GTE shall
     report investigative findings in writing. Upon request of Genuity, GTE
     shall report material findings of criminal acts to the appropriate State or
     Federal criminal justice agency.

                                 Page 17 of 22
<PAGE>

Genuity's Responsibilities with respect to Irving-Based Building Security
-------------------------------------------------------------------------
Services
--------

Genuity shall provide all information required for GTE to perform its duties
hereunder, including without limitation current notification information in the
event of an alarm.

Pricing Structure with respect to Irving-Based Building Security Services
-------------------------------------------------------------------------

     ID Badge                                        $ 2.50 each
     ID Badge & Keycard Combination                  $ 5.00 each

     Alarm Monitoring                                $30.00 per month

     Investigative Services (Other than
     Computer Forensic Investigative Services)       $ 60.00 per hour

     Computer Forensic Investigative Services        $150.00 per hour

Hourly rates will be charged for all time spent on investigative services,
including without limitation all time associated with conducting investigations,
reviewing documents, preparing reports and correspondence and attendance at
meetings.

In addition to these fees and charges, Genuity shall reimburse GTE for all
travel-related costs and expenses in accordance with the terms of the agreement
and for all costs and expenses for long distance, communications, reproductions,
courier and delivery services, postage and supplies incurred by GTE in the
performance of these services. GTE shall submit quarterly invoices to Genuity
for these Irving-based security services.

Other Specific Terms or Conditions with respect to Irving-Based Building
------------------------------------------------------------------------
Security Services
-----------------

GTE may use GTE-approved subcontractors to provide any of the Irving-based
building security services described in this SOW, with supervision of such
subcontractors to be provided by GTE; however, Genuity shall not be responsible
for the costs of such subcontractors except as expressly set forth herein.

The parties acknowledge and agree that the alarm monitoring equipment located at
Genuity's premises is owned by Genuity and that Genuity has sole responsibility
for the repair and maintenance of such equipment. GTE has no obligations or
responsibilities with respect to repair and maintenance of such equipment.

Any or all of the Irving-based security services described in this SOW may be
terminated by Genuity for any or no reason upon 60 days written notice. In the
event of termination, Genuity shall pay GTE for all services performed through
the date of termination.

LIMITATIONS WITH RESPECT TO IRVING-BASED BUILDING SECURITY SERVICES
-------------------------------------------------------------------

     GTE does not warrant services against intrusion, loss, property damage,
     vandalism, or injury to employees, visitors or contractors.

                  CAMBRIDGE-BASED BUILDING SECURITY SERVICES

                                 Page 18 of 22
<PAGE>

Genuity Security provides ID badge and card key issuance, alarm monitoring,
guard services and investigative services for certain GTE buildings in
Cambridge, MA, New London, CT, Rosslyn, VA, and Columbia, MD. These services are
provided from a central security control center located in a GTE-owned building
in Cambridge, MA. Genuity uses this same security control center to monitor
numerous other Genuity sites. Accordingly, GTE has agreed to lease the security
control center to Genuity during a transition period to allow Genuity time to
design and construct an alternate security control center at another site. In
turn, during this transition period, while Genuity has exclusive use and control
of the security control center in Cambridge, MA, Genuity has agreed to provide
certain security services to GTE. These services shall terminate no later than
December 31, 2000; however, Genuity may terminate these services upon 30 days
written notice provided that Genuity's lease of the security control room
likewise terminates upon the date of termination of these services as set forth
below.

The Cambridge-Based Building Security Services to be provided under this SOW are
to be provided under the terms and conditions of the Agreement, EXCEPT for
purposes of these Cambridge-Based Building Security Services the service
provider is Genuity and the customer is BBNT Solutions LLL ("BBNT"), an
affiliate of GTE. Accordingly, for purposes of these Cambridge-Based Building
Security Services, (i) Genuity agrees to be bound by the terms of the Agreement
as if it were GTE thereunder, and (ii) GTE and BBNT shall be bound by the terms
of the Agreement as if they were Genuity thereunder.

1.   Genuity shall provide security management and system monitoring services as
     described below:

     .    Genuity will provide 24 hour monitoring of the currently installed
          security management system in BBNT's buildings in Cambridge, MA; New
          London, CT; Rossalyn, VA; and Columbia, MD; and will provide
          notification of alarms to BBNT in accordance with instructions from
          BBNT. BBNT is responsible for providing current notification
          information.
     .    Genuity will provide a weekly alarm report and a list of authorized
          card users generated from the DSX security management system.
     .    Genuity will provide response to intrusion alarms on perimeter doors,
          medical emergencies, and other emergency situations. Genuity also will
          provide after-hour employee escorts and vehicle assistance. Genuity
          will provide reasonable response time to service requests, but actual
          time depends on other required duties performed by security personnel.
     .    Genuity will maintain the access control system in proper working
          order at its cost and expense; however, BBNT shall reimburse Genuity
          for all repair costs resulting from the negligence or willful
          misconduct of BBNT or its employees, agents or contractors.
     .    BBNT owns the security system components located in its owned and
          leased buildings covered by this SOW (specifically excluding BBNT's
          subleased premises located at 70 Fawcett Street, Cambridge, MA),
          EXCEPT Genuity owns the security console and the equipment located
          therein in the security control center located at 77 Fawcett Street,
          Cambridge, MA.

2.   Genuity shall provide access control cards and keys as described below:

                                 Page 19 of 22
<PAGE>

     .    Genuity will provide access control cards and photo identification to
          BBNT employees in accordance with currently established procedures.
     .    Genuity "owns" the facility code presently used on access control
          cards. Upon expiration or earlier termination of this SOW with respect
          to Cambridge-based security services, BBNT will endeavor to recover
          and return to Genuity the access control cards issued by Genuity.
     .    Genuity will process photo identification / access control cards in
          accordance with the current badge office hours and procedures.
     .    BBNT will provide Genuity with photo badge templates in digital
          format.
     .    Cost of the first 100 badges per month is included in the monthly
          Security Management Fee. BBNT shall pay a fee of $25 per badge for
          each additional badge in excess of 100 badges issued in any month.
     .    Genuity will maintain the current mechanical key hierarchy until BBNT
          installs an alternate hierarchy. Costs of keys will be included in the
          Security Management Fee. Re-coring costs will be charged at cost +
          10%.

3.   Genuity shall perform investigative services for BBNT as described below:

     .    Genuity will provide initial response to reports of internal thefts,
          security complaints and other security-related matters. Genuity's
          initial response and report is included in the Security Management
          Fee.
     .    Upon request by BBNT, Genuity may provide further investigation beyond
          initial response and report at a cost of $75 per hour. BBNT shall
          reimburse Genuity for all travel-related costs and expenses associated
          with investigations in accordance with BBNT's travel policy. If
          Genuity does not have the capacity or desire to perform investigations
          beyond initial response and report, Genuity shall decline to provide
          such additional investigative services; Genuity shall not retain any
          third party consultants or investigators for or on behalf of BBNT.
     .    BBNT is responsible for background investigations of BBNT new hires

4.   Genuity shall provide guard services to BBNT as described below:

     .    Genuity shall provide routine guard services in accordance with
          existing practices, including guard patrol services to internal and
          external BBNT property and initial emergency response. Genuity will
          manage the guard services.
     .    If BBNT requests any special guard services for moves or other special
          events, BBNT shall pay the direct costs incurred by Genuity in
          accordance with Genuity's guard service contract, plus a 10%
          management fee, for such additional coverage.
     .    Routine guard tours will include required checks of government secured
          containers and rooms.
     .    Genuity will provide government "cleared" guards until May 31, 2000
          and will provide required response to secure open government
          containers and rooms in accordance with present practices. Genuity
          will not maintain the capability to provide "cleared" response beyond
          May 31, 2000.

Term for Cambridge-Based Building Security Services and Transition of Services
------------------------------------------------------------------------------

The parties acknowledge that Genuity is leasing the space for the security
control center located at 77 Fawcett Street from BBNT under the terms of a Lease
Agreement of even date herewith.

                                 Page 20 of 22
<PAGE>

The parties further acknowledge and agree that it is the intention of both
parties to transition the security services covered by this SOW from Genuity to
BBNT on or before December 31, 2000. In furtherance of this transition, Genuity
hereby agrees to diligently proceed with the selection, design, and build-out of
an alternate security control center to which it will migrate all non-BBNT
security management and monitoring conducted by Genuity at 77 Fawcett Street.

This SOW shall terminate with respect to the Cambridge-based security services
upon the earlier of (i) December 31, 2000, or (ii) 30 days after written notice
of termination from Genuity to BBNT; it being understood and agreed that
Genuity's lease of the security control room likewise shall terminate upon the
date of termination of this SOW. Upon termination of this SOW, the parties agree
to cooperate with each other in transitioning the security services provided
hereunder to BBNT or its designated third party provider.

In addition, and notwithstanding anything to the contrary contained in this SOW,
BBNT may terminate this SOW with respect to the guard services described in
paragraph 4 above upon 30 days written notice to Genuity.

BBNT's Responsibilities with respect to Cambridge-Based Building Security
-------------------------------------------------------------------------
Services
--------

BBNT shall provide all information required for Genuity to perform its duties
hereunder, including without limitation current notification information in the
event of an alarm. As stated above, BBNT also will provide Genuity with photo
badge templates in digital format.

Pricing Structure with respect to Cambridge-Based Building Security Services
----------------------------------------------------------------------------

Genuity may use Genuity-approved subcontractors to provide any of the
Cambridge-based building security services described in this SOW, with
supervision of such subcontractors to be provided by Genuity; however, BBNT
shall not be responsible for the costs of such subcontractors except as
expressly set forth herein.

In addition to the fees set forth elsewhere herein, BBNT shall pay Genuity the
following fees for these services:

     System Monitoring Service (including all
     system maintenance and repairs, except
     as expressly set forth in this SOW)             $5,400.00 per month

     Security Management Fee                         $2,675.00 per week

     Routine Guard Services Fee                      $3,330.00 per week

Genuity shall submit monthly invoices to GTE for these Cambridge-based security
services.

LIMITATIONS WITH RESPECT TO CAMBRIDGE-BASED BUILDING SECURITY SERVICES
----------------------------------------------------------------------

     Genuity does not warrant services against intrusion, loss, property damage,
     vandalism, or injury to employees, visitors or contractors. The success of
     any security program is contingent upon the active participation of all
     employees, visitors and contractors and requires the support of all levels
     of management.

                                 Page 21 of 22
<PAGE>

GTE SERVICE CORPORATION                 GENUITY SOLUTIONS INC.

By:____________________________         By:_____________________________

Title:_________________________         Title:__________________________

                                 Page 22 of 22
<PAGE>

                                                                    ATTACHMENT 4

                               STATEMENT OF WORK

                                      FOR

                               BILLING SERVICES

This Statement of Work ("SOW") is made by GTE Consolidated Services
Incorporated, ("CSI") and Genuity Solutions Inc., and its subsidiary companies
(collectively referred to as "GENUITY"), and is hereby made a part of and shall
be governed by the Transition Services Agreement.

This SOW establishes the terms and conditions pursuant to which GENUITY wishes
to obtain from CSI, and CSI shall provide to GENUITY, billing, credit and
collection services for GENUITY for a transitional period of one (1) year. This
SOW may not be renewed. During the transition period, GENUITY requires various
billing, credit and collection services in order to properly bill and receive
revenue from its customers. CSI has in the past, and continues to possess, the
capability of providing such billing, credit and collection services to meet the
billing, credit and collection needs of GENUITY for the continuing and
uninterrupted flow of revenue to GENUITY.

1.   SERVICES IN GENERAL.

     (a)  This SOW establishes the terms and conditions pursuant to which
GENUITY shall obtain from CSI, and CSI shall provide to GENUITY, billing, credit
and collection services regarding GENUITY's corporate/commercial customers
(individually and collectively, "Services") described in various schedules to
this SOW (individually a "Schedule" and collectively the "Schedules"). To the
extent of any conflict or inconsistency between the terms and conditions of a
Schedule and the terms and conditions of this SOW, the terms and conditions of
the applicable Schedule shall control.

     (b)  All Schedules shall: be and are hereby incorporated by reference as a
part of this SOW and shall: (i) describe the type and scope of Services to be
performed, resources to be provided or obligations to be discharged by CSI
pursuant to the SOW; (ii) describe the obligations of GENUITY related to this
SOW, including any facilities, equipment, personnel and tasks or other support
to be provided or performed by GENUITY; (iii) specify any other terms and
conditions appropriate to the Services to be performed and the obligations of
the parties relative thereto. The attached Schedules are as follows:

               Schedule A-Description of Services

               Schedule B-Performance Standards

               Schedule C- Current Products Billed
<PAGE>

               Schedule D-Change Request Procedures

               Schedule E- Arbor Conversion

               Schedule F-ATM Services

               Schedule G- Pricing

               Schedule H- Tax Services

     (c)       No changes to the scope of Services shall be permitted unless set
forth in writing pursuant to the procedures set forth in Schedule D, Change
Request Procedures.

2.   CREDIT AND COLLECTION SERVICES.

     (a)  CSI shall perform the credit and collection Services set forth in the
Schedules, upon written request by GENUITY.

     (b)  In addition to the provisions of the Transition Services Agreement
concerning Compliance with Laws, with regard to Credit and Debt Collection, the
parties, their employees, contractors, agents and assigns shall comply with all
applicable federal, state and local credit and debt collection statutes,
ordinances, regulations, and codes including but not limited to the Fair Credit
Reporting Act, 15 U.S.C. Section 1681, et seq., The Equal Credit Opportunity
Act, 15 U.S.C. Section 1691, et seq., The Fair Debt Collection Practices Act, 15
U.S.C. Section 1692, et seq., and the Consumer Credit Protection Act, 15 U.S.C.
Section 1601, et seq.

3.   INFORMATION TECHNOLOGY REQUIREMENTS.

CSI will provide such records and data processing tools as necessary, to provide
the Services set for herein, either through its own information technology
("IT") resources or those of its affiliates and third party contractors.
GENUITY will give CSI prompt written notice of any modifications to its existing
records and data systems, when it augments such systems or obtains new records
and data systems, that may materially affect CSI's ability to provide services
hereunder.

4.   REPLACEMENT AND MODIFICATION OF SYSTEMS.

CSI reserves the right to modify or replace its billing systems at any time
during the term hereof, to support increased capacity or new products or
services requested by GENUITY or required for the performance of Services by CSI
("Changes"), provided, however, such Changes will not result in any material
loss of functionality of such billing systems or Services. CSI shall give
GENUITY immediate notice of such Changes.

CONFIDENTIAL INFORMATION-Subject to Protective Order in CC Docket No. 98-184
before the Federal Communications Commission

                                       2
<PAGE>

GENUITY understands and agrees that as used herein, the term "billing systems"
shall refer solely to the protocol that CSI employs in tandem with the
particular transmission medium used by GENUITY that enables CSI to read and
process GENUITY's data as detailed in the Schedules and any attachments thereto.

5.   SERVICES PRICING AND INVOICING

     (a)  Pricing for CSI Services is set out in Schedule G, Services Pricing.
Such pricing does not include applicable sales, use or similar taxes, which
shall be added to the amount invoiced.

     (b)  In addition to the provisions set forth in the Transition Services
Agreement, GENUITY agrees to pay the full invoiced amount represented on each
invoice, or in the event that an amount is in dispute, submit a written request
for review of the disputed portion of the invoice by the payment due date of the
invoice. If GENUITY fails to pay or submit a request for review of a disputed
billing procedure, as provided herein, by the payment due date, CSI reserves the
right to charge interest at a rate of 1 1/2 % per month or at the highest
allowable statutory rate. In the event of a dispute concerning an invoice
received by GENUITY, GENUITY shall promptly notify CSI in writing of the
disputed item(s) with a description of the dispute on or before the due date of
the invoice. CSI shall respond within 20 days of receipt of such dispute. If the
dispute cannot be resolved by the parties within 30 days thereafter, the parties
will resort to the dispute resolution procedures set forth in the Transition
Services Agreement.

     (c)  In addition to the provisions for expense reimbursement set forth in
the Transition Services Agreement, GENUITY shall reimburse CSI for all
reasonable expenses approved by GENUITY, incurred on GENUITY's behalf for the
purposes of providing the Services ("Expenses"). There shall be no mark-up for
invoiced Expenses. CSI shall invoice GENUITY for Expenses as they accrue
monthly.

     (d)  The parties shall negotiate pricing within 120 days of the anniversary
of this SOW as set out in Section 6 (b) Term with new pricing to be effective on
the anniversary date of this SOW. However, CSI reserves the right to increase
its rates and charges at any time during the term or any renewal term to include
increases in costs as the result of changes in Applicable Law, regulation, or
postal rates, or other similar circumstances beyond CSI's control, related to
CSI's provision of Services, whether recurring or non-recurring, upon thirty
(30) days written notice to GENUITY.

Upon GENUITY's termination of this SOW, for convenience before the end of the
initial term, as provided in Section 6, prior to the end of the term, GENUITY
will reimburse CSI, its parent or affiliate, as the case may be, for all
GENUITY-approved, third party

CONFIDENTIAL INFORMATION-Subject to Protective Order in CC Docket No. 98-184
before the Federal Communications Commission

                                       3
<PAGE>

costs for equipment or software which have been incurred by CSI after the
execution of this SOW as a direct result of CSI's provision of Services under
this Agreement or any Statement of Work, provided that GENUITY shall be entitled
to any right, license or title related to any such equipment or software to the
extent CSI has the legal authority to convey such right, license or title. In
addition, in the event GENUITY terminates this SOW for convenience during the
term or any renewal term, GENUITY will reimburse CSI for $8 million of the $16
million license fee paid by CSI, its parent or affiliated company, as the case
may be, for the Kenan-Arbor Software License.

6.   TERM.

     (a)  This SOW is effective as of the Effective Date of the Transition
Services Agreement and shall continue in full force and effect for an initial
term ("Initial Term") of one (1) year. This SOW may not be renewed..

     (b)  Termination without Cause. Either party may terminate this Statement
          -------------------------
of Work without cause upon a minimum of one hundred and eighty (180) days
written notice to terminate. The parties agree that this notice period is longer
than the 120 day termination provision set out in the basic Agreement, and agree
to the longer period in order to accommodate GENUITY's minimum requirements in
transitioning to another service provider or another billing and collection
mechanism. Upon receipt of notice of termination, the parties shall meet to
determine a plan for transition and termination, the termination date shall not
be longer than one year from the date the non-terminating party receives such
notice of termination.

     (c)  Termination for Cause. GENUITY may terminate this Statement of Work
          ---------------------
for cause, upon written notice and with an opportunity to cure pursuant to the
Transition Services Agreement, due to CSI's material failure to administer
GENUITY's established policies and procedures (which have been given to CSI in
writing prior to such alleged failure). For purposes of this agreement,
"material failure" is defined as the occurrence of either: (i) three (3) or more
breaches of separate policies or procedures within a twelve (12) month rolling
period or (ii) two (2) or more breaches of the same policy or procedure within a
rolling twelve (12) month period.

     (d)  In addition to the foregoing, this SOW may be terminated by: (i)
mutual agreement of the parties or (ii) in the event of termination of the
Transition Services Agreement, this SOW will terminate simultaneously therewith.

CONFIDENTIAL INFORMATION-Subject to Protective Order in CC Docket No. 98-184
before the Federal Communications Commission

                                       4
<PAGE>

7.   CSI ON- SITE PERSONNEL.

     (a)  CSI shall provide on-site personnel at specifically designated GENUITY
location(s) to support GENUITY's requirements as mutually agreed by the parties.
All such on-site personnel will work under the direction and control of CSI.

     (b)  CSI shall be responsible for all timekeeping, payroll, applicable
benefits (if any), workers compensation, insurance, employment and other related
taxes, documentation and related administrative duties or other requirements
with respect to the CSI on-site personnel.

     (c)  CSI shall require all employees or subcontractors located on-site at
GENUITY's location(s) to comply with the published rules, regulations and
policies of GENUITY which shall be provided to all on-site employees at the time
the on-site employee is assigned to an GENUITY location(s).

     (d)  CSI and the on-site personnel shall treat and maintain all information
obtained at GENUITY's location(s) as Confidential Information as set forth in
the Transition Services Agreement.

     (e)  In the event that GENUITY requires on-site personnel, GENUITY will
provide adequate office space and accommodations to support such on-site
personnel. The term "adequate office space and accommodations" means that
GENUITY shall provide, including but not be limited to, office space
specifically designated for CSI employees in or near GENUITY's offices equipped
with computers, telecommunications, e-mail, internet access, ordinary and
customary office furniture and equipment and mail and janitorial services.

     (f)  In the event that GENUITY requires the office relocation of any on-
site personnel provided by CSI, GENUITY will reimburse CSI for all business-
related costs incurred by CSI associated with relocation of CSI personnel as set
forth herein.  8.

     ACCESS NEEDS OF PARTIES AND CONFIDENTIALITY PROTECTIONS FOR PERSONNEL ON
SITE TO EITHER PARTY.

In addition to the provisions set forth in the Transition Services Agreement,
each party shall permit reasonable access during normal working hours to its
facilities and systems that are used in connection with the performance of
Services.  On-site personnel shall be given security authorization for limited
access to GENUITY's facilities for the purpose of performing the Services.  For
all other types of access by non on-site personnel, reasonable prior notice
shall be given when access is required.

CONFIDENTIAL INFORMATION-Subject to Protective Order in CC Docket No. 98-184
before the Federal Communications Commission

                                       5
<PAGE>

9.   FORECASTING

In order to permit CSI to plan for and implement the Services, GENUITY shall
provide CSI with quarterly forecasts of billing volumes for each fiscal quarter
during the term hereof.  Each quarterly forecast must be submitted to CSI no
later than 60 days prior to the end of the preceding quarter and such forecast
shall provide:

         (1) volume of gross billing (in dollars),

         (2) percentage increase or decrease in volume of amounts billed,

         (3) billing volume for new customers and estimated dollar value.

         (4) Number of Customers- Broken out into classifications: Total, New
             and Incremental (increase or decrease)

         (5) Number of Usage Records (for usage products) per month, per
             product; date expected to be made available to billing; requested
             in-service date

         (6) Number of Non-Usage Billing Events: NRC's and MRC's per month, per
             product; date expected to be made available to billing; requested
             in-service date

         (7) Volume of Individual Customer Basis contracts

         (8) Activation time required for new customer or new products to
             introduced in the applicable quarter and the effective date for the
             following:
                  (i)    new products
                  (ii)   new customers
                  (iii)  new pricing
                  (iv)   bundled services and/or pricing

         (9) Requirements for development of new billing capabilities or changes
             to existing capabilities pursuant to Schedule D, Change Request
             Procedures.

     The parties acknowledge that material changes to billing events processed
     by the CSI system, including but not limited to, introduction of new
     products, the addition of a significant number of new customers,
     significant deviations from forecasted volumes or significant increases in
     billing volumes, or delays from forecasted dates in launching new products
     may lead to limitations on CSI's ability to provide the Services.  In order
     to provide CSI with the best available information concerning GENUITY's
     projected volumes and changes that have an impact on CSI's provision of the
     Services described in this SOW, the parties shall meet quarterly to review
     GENUITY's forecast for the next quarter to determine

CONFIDENTIAL INFORMATION-Subject to Protective Order in CC Docket No. 98-184
before the Federal Communications Commission

                                       6
<PAGE>

          the requirements of each party in order for CSI to provide the level
          of Services required by this SOW.

     10.  CHANGE CONTROL.

          (a)  All requests for changes to or addition of Services for new
     products, new customers, termination of customers, significant
     increases/decreases to numbers of bills or other changes regarding the
     Services must be made in accordance with the Change Request Procedures set
     forth at Schedule D.

          (b)  In addition, GENUITY shall communicate all IT requirements,
     changes, clarification, question or requests of any nature regarding the
     CSI system directly to CSI personnel or management. In no event shall
     GENUITY communicate directly with any affiliates or subcontractors of CSI
     regarding such requests or other components or services rendered pursuant
     to this SOW without the written consent of CSI.

     11.  TAXES.

(a)  CSI shall provide the tax services described in Schedule H, Tax Services.
     GENUITY shall be liable for all applicable sales, use or similar taxes for
     amounts invoiced to GENUITY's customers and GENUITY shall be responsible
     for preparation and filing of all tax returns and applicable tax reporting
     to all taxing jurisdictions.  Taxes shall be added to each customer's
     invoice, however, CSI shall not be liable for miscalculation or omissions
     with regard to such taxes.

     12.  MODIFICATION

     This SOW or any Schedule attached hereto may only be modified or amended by
     an instrument in writing signed by duly authorized representatives of the
     parties pursuant to the terms of the Transition Services Agreement.

CONFIDENTIAL INFORMATION-Subject to Protective Order in CC Docket No. 98-184
before the Federal Communications Commission

                                       7
<PAGE>

IN WITNESS WHEREOF, the parties hereto have executed this SOW through their
authorized representatives.

GTE Consolidated Services Incorporated  Genuity Solutions Inc.

By: ____________________________        By:___________________________

Name:___________________________        Name:_________________________

Title:__________________________        Title:________________________

Date:___________________________        Date:_________________________

CONFIDENTIAL INFORMATION-Subject to Protective Order in CC Docket No. 98-184
before the Federal Communications Commission

                                       8
<PAGE>

                                                                   ATTACHMENT 4A

                                  Schedule A
                        Description of Billing Services

The scope of the Services set forth herein may be modified by mutual agreement,
but all modifications must be in writing, signed by both parties. CSI shall
perform no services outside the scope of the Services as defined in writing in
this Schedule A. No changes to the scope of work shall be permitted unless set
forth in writing executed by an authorized manager of each party (for purposes
of authorization, e-mail will not be considered a "writing").

Under this SOW, CSI agrees to provide to GENUITY the following functions, which
collectively are defined as Billing Services:

 .  Data Accumulation
 .  Bill Processing
 .  Bill Format and Distribution
 .  Inquiry & Investigation
 .  Credit Verification
 .  Collections Administration
 .  Payment Processing
 .  Administration of Billing Capability

The following sections describe each of these functions and the roles and
responsibilities of CSI and GENUITY in fulfilling these functions.

Section 1.0 - Data Accumulation

1.0   Data accumulation consists of the validation and correction (as agreed
upon) of usage based billing events, trending, guiding of usage based events to
a customer account, provisioning of unrated and/or rated call detail files as
agreed upon and preparing usage based events for bill calculation process. Such
events may be voice, data, database lookups and value added services. Events can
be recorded by GENUITY'S network or received from an external company.

1.1   CSI will:

1.1.1 Validate and manage usage based billing events on a timely basis (daily),
      from mediation to billing, and process those records for billing in
      accordance with the business rules defined by GENUITY. In situations where
      GENUITY performs the collection and mediation processes, CSI will accept
      only those records which are in the standards and format defined by CSI.

1.1.2 Provide balancing and control procedures to assure all usage based billing
      events provided by GENUITY are processed and distributed to the billing
      systems in an accurate and timely manner.

CONFIDENTIAL INFORMATION-SUBJECT TO PROTECTIVE ORDER
IN CC Docket No. 98-184 before the Federal Communications Commission

                                       1
<PAGE>

1.1.3 Investigate all events in error and return to GENUITY for review and
      disposition any errors that CSI cannot correct.

1.1.4 Perform trending on billing events and provide reporting to GENUITY for
      their analysis of customer behavior and impact on revenues

1.1.5 Provide monthly reports to GENUITY on the volume of usage based billing
      events processed, volume of events determined to be unbillable due to
      errors, and root cause analysis of event processing errors.

1.2   GENUITY will:

1.2.1 Provide to CSI scheduled usage based event transmissions in the format and
      standards as mutually agreed to by the parties.

1.2.2 Provide to CSI usage based event transmission balancing and control
      information in the format and standards as mutually agreed to by the
      parties.

1.2.3 Notify CSI of any delays in scheduled transmissions and will not hold CSI
      responsible for any missed cycle cutoffs due to delays caused by GENUITY.

1.2.4 Notify CSI of usage rate changes in a timely manner and will not hold CSI
      responsible for any missed rate change update due to delays caused by
      GENUITY. Rate changes and any new usage based events to be billed will be
      communicated to CSI as outlined in Schedule D- Change Request Procedures

Section 2.0 - Bill Processing

2.0 Bill Processing consists of the creation of formatted billable data for all
    customers at bill now time. This process includes the retrieval of all
    usage-based events, customer specific product and services information,
    recurring and non-recurring charges, adjustments to customer accounts and
    payment data.

2.1   CSI will:

2.1.1 Maintain billing schedules in accordance with GENUITY business
      requirements. Billing schedules will be prepared on a monthly basis and
      approved by GENUITY and CSI. Any changes in final mail dates to customers
      will be mutually agreed on by both parties.

2.1.2 Calculate all federal, state, and local sales, use, excise, gross
      receipts, and other taxes and tax-like charges imposed on GENUITY's
      services in accordance with the tax application guidelines provided by
      GENUITY.

                                       2
<PAGE>

2.1.3 Develop and maintain the billing process for GENUITY's pricing and
      discounting plans for products and services offered by GENUITY.

2.1.4 Perform quality assurance reviews of billing system outputs to verify the
      accuracy of billing and take the required action to correct billing
      exceptions identified.

2.1.5 Maintain financial and journalization tables to ensure the accurate
      transmission of billing data to GENUITY's Financial Reporting system, SAP.

2.1.6 Maintain billing data files for the period of time consistent with
      applicable law and GENUITY business requirements.

2.1.7 Provide security controls for usage based event and billing data to assure
      only those organizations/individuals authorized by GENUITY have access to
      such data.

2.2   GENUITY will:

2.2.1 Provide to CSI information regarding new pricing and discount plans or
      changes to existing pricing and discount plans as outlined in Schedule D-
      Change Request Procedures.

2.2.2 Provide direction and business requirements to CSI regarding the
      application and billing of Taxes, including, without limitation,
      implementation of the following:

          2.2.2.1   Procedures or information relating to taxes that are
          applicable to GENUITY products and services for all taxing
          jurisdictions.

          2.2.2.2    Procedures or information arising from changes to
          Applicable Law relating to Taxes.

          2.2.2.3    Procedures or information relating to Taxes on new products
          and services offered by GENUITY.

          2.2.2.4    Procedures or information relating to Tax surcharges.

          2.2.2.5    Procedures or information relating to the tax status of a
          particular customer.

2.2.3 Provide CSI with GENUITY's requirements related to the information flow
      from the billing system as applicable to journalization of revenues, cash,
      accounts receivable and uncollectible activity processed by CSI's billing
      systems.

                                       3
<PAGE>

2.2.4 Provide CSI customer sales, order entry, and provisioning data on a daily
      schedule as input to the billing function performed by CSI. These updates
      shall include for new GENUITY customers, all account information necessary
      to establish an account on the billing system customer account database.
      For existing customers, these updates shall include all changes to the
      account and the effective date of the change.

2.2.5 Provide to CSI such access to GENUITY sales, order entry, provisioning and
      financial systems that are required in order to supply the billing system
      with appropriate customer or product related data required by CSI in the
      preparation of a customer bill.

2.2.6 Provide for CSI maintenance and training on GENUITY systems that require
      access by CSI employees.

2.2.7 Provide to CSI an initial list of GENUITY employees authorized by GENUITY
      to access and review customer data and product/service data from CSI's
      billing systems. Updates to this list will be communicated to CSI on no
      less than a monthly basis and immediately upon the termination of any
      previously authorized employee.

2.2.8 Provide to CSI on no less than a monthly basis, a report of known or
      suspected billing issues detected by GENUITY from any source, including
      but not limited to customer feedback or inquiries and analysis of
      financial reporting data.

Section 3.0 - Bill Format and Distribution:

3.0   Bill Format and Distribution consists of the processes used to support the
      production of the bill in the format and on the media defined by GENUITY
      business requirements and the distribution of the bill and any
      supplemental information to the customer.

      3.1   CSI will:

3.1.1 Maintain and support bill presentation formats in paper media. Support for
      invoice preparation on alternative media (CD-ROM, diskette, electronic)
      will be evaluated through the Change Request Procedures based on GENUITY's
      business requirements, See Schedule D.

                                       4
<PAGE>

3.1.2 Provide balancing and control processes to assure all print files are
      received, processed and distributed in accordance with established Bill
      Processing schedules.

3.1.3 Manage the investigation and corrective action associated with any
      files/documents that are not successfully transmitted and printed.

3.1.4 Burst, fold, insert, apply postage and mail all customer bills in
      accordance with Bill Processing schedules.

Administer the recovery of mutilated bills utilizing CSI's standard bill reprint
process.

3.1.5 Provide to GENUITY a confirmation of the total documents mailed by cycle,
      by entity for each processing date.

3.1.6 Provide for the preparation and distribution of supplemental information,
      primarily call detail reporting, in paper and electronic media. Support
      for supplemental detail information on alternative media, including CD-ROM
      and diskette will be evaluated through the Change Request Procedures set
      forth in Schedule D based on GENUITY's business requirements.

3.1.7 Perform inventory control and ordering of forms for GENUITY bills and
      envelopes to assure proper stock levels.

3.1.8 Adhere to required USPS regulations and will manage the distribution
      process to assure the most favorable postage rates to GENUITY.

3.1.9 Support the mailing of promotional and informational material (commonly
      referred to as bill inserts) in GENUITY's bill mailings or through direct
      mailing to selected customers.

GENUITY will:

3.2.1 Notify CSI of any changes to paper stock or envelopes 75 days in advance
      to allow for lead-time and restocking.

3.2.2 Provide sample inserts to CSI for testing at least 5 business days prior
      to designated bill dates.

3.2.3 Define business requirements and provide test data for any new bill
      formats or media that GENUITY deems necessary to meet business or customer
      demands. GENUITY will follow the guidelines in Schedule D-Change Request
      Procedures, when requesting a change by CSI.

                                       5
<PAGE>

Section 4.0 - Inquiry and Investigation

4.0   Inquiry and Investigation consists of those processes necessary to answer
      and resolve questions received from GENUITY's customers regarding their
      bill or billing services, such as questions concerning receipt of payment,
      request for duplicate bill copy, change of address, an explanation of the
      bill or referral of a billing issue from an GENUITY employee. An inquiry
      may be received by phone, automated attendant, voice mail, facsimile, or
      electronic means.

4.1   CSI will, pursuant to GENUITY's policies, procedures and at GENUITY's
      direction:

4.1.1 Support customer billing inquiry and adjustment functions as defined by
      GENUITY, including providing Customer Billing Inquiry Representatives to
      answer direct calls from GENUITY customers on matters related to the
      customer bill.

4.1.2 Provide Customer Billing Inquiry Representative and management support
      staffing for those hours of service currently defined as 8:00 AM to 5:00
      PM Eastern and Central standard time.

4.1.3 Provide the necessary training and monitoring of employee performance to
      assure that employees are performing in accordance with GENUITY business
      policies.

4.1.4 Manage and perform billing-related problem investigation, resolution and
      tracking for customer reported billing issues that cannot be handled
      during the customer bill inquiry process. CSI will take the required
      actions to correct problems within the billing processes and billing
      systems. If the issue investigation process determines the problem is a
      result of errors in systems or processes managed by GENUITY, CSI will
      inform GENUITY and will assist GENUITY as requested through the resolution
      process.

4.1.5 Perform root cause analysis of bill inquiry calls to determine appropriate
      level of resolution within the billing process to minimize recurring
      customer impact and to reduce subsequent calls.

4.1.6 Provide to GENUITY monthly reports of compliance to performance standards
      and service levels and of root cause analysis of inquiry calls.

4.2   GENUITY will:

                                       6
<PAGE>

4.3   Provide necessary telecommunications support and network integration to
      meet service level standards and provide ongoing support of all 800
      numbers assigned for customer inquiry.

4.2.1 Provide to CSI copies of all information necessary for CSI to train its
      Customer Inquiry representatives and supervisory staff to answer customer
      questions regarding information contained on their bill. This information
      will include, but is not limited to: product and service descriptions,
      availability of products and services, rate and pricing schedules,
      promotional terms and conditions, and any customer specific contracts
      and/or terms and conditions. Information should be received by CSI no
      later than 15 days prior to the change being effective.

4.2.2 Provide to CSI business policies outlining its customer services standards
      including, but not limited to the amount a CSI Customer Inquiry
      representative may adjust from a customer's bill, supervisory approval
      levels for adjustment activity, and escalation procedures for when a
      customer should be referred to an GENUITY representative/officer for
      problem resolution.

4.2.3 Provide CSI personnel with access to any non-billing systems that are
      necessary for the investigation and resolution of billing related
      questions. These systems include but are not limited to sales/order entry
      systems, pending order activity, provisioning, trouble reporting systems.
      GENUITY will provide the ongoing maintenance and support of these systems,
      including the cost of access to and processing of transactions generated
      by CSI personnel on behalf of GENUITY customers.

4.2.4 Commit to make the necessary changes in it's supporting systems for errors
      that are causing errors in the billing system. All costs to correct these
      systems will be borne by GENUITY. GENUITY will also bear the costs of
      correcting problems in CSI maintained billing systems.

Section 5.0 - Credit Verification

5.0   Credit Verification consists of those administrative functions necessary
      to perform credit checks to determine credit worthiness of new GENUITY
      customers, in accordance with standards established by GENUITY, and to
      communicate the results of these findings to GENUITY management for
      further actions.

5.1   CSI will, pursuant to GENUITY's policies, procedures and at GENUITY's
      direction:

                                       7
<PAGE>

5.1.1 Determine credit worthiness of new customers in accordance with standards
      established by GENUITY.

5.1.2 Determine credit worthiness of current GENUITY customers who add new
      products and services over their approved credit limit, in accordance with
      standards established by GENUITY.

5.1.3 Notify GENUITY sales personnel when the credit verification process
      determines a deposit may be required from a customer prior to the
      establishment of service.

5.1.4 Refer to GENUITY management reports of customers who do not pass credit
      checks and the reasons for denial under the standards established by
      GENUITY.

5.1.5 Maintain contracts with major credit reporting bureaus, both domestic and
      international, that are required in order to fulfill the credit
      verification described above.

5.2   GENUITY will define credit worthiness standards for new and current
      customers wishing to add services. Any changes to these policies will be
      communicated to CSI no later than 15 days prior to their effective date to
      allow for changes to operating procedures and system parameters.

Section 6.0 - Collections Administration

6.0   Collections administration consists of those functions necessary to
      support the risk management policies established by GENUITY and to assist
      GENUITY in minimizing the loss of GENUITY billed revenues.

6.1   CSI will:

6.1.1 For accounts that are in a delinquent status as defined by GENUITY
      business policies, perform collection activities including sending
      collection letters to customers, resolving billing disputes and contacting
      customers in an attempt to collect.

6.1.2 In accordance with GENUITY business policies CSI will notify GENUITY
      management when a customer's account reaches the thresholds established by
      GENUITY for unacceptable balances or delinquent payment, . Upon direction
      from GENUITY management, CSI will return the customer account to GENUITY
      for disposition or refer the debt to an outside collection agency.

                                       8
<PAGE>

6.1.3 Provide monthly, a report of accounts receivable aging, average collection
      period and amount of uncollectible write-offs and recoveries for the
      period.

6.1.4 Refer any accounts that are identified during the collections process as
      being in bankruptcy, receivership, probate, etc. to GENUITY's Legal
      department for further action. CSI will write off these accounts as
      directed by GENUITY.

6.2   GENUITY will:

6.2.1 Define policies for the treatment and collection of delinquent accounts.
      Any changes to these policies will be communicated to CSI no later than 15
      days prior to their effective date to allow for changes to operating
      procedures and system parameters.

Section 7.0 - Payment Processing

7.0   Payment Processing includes those activities necessary to post/update
payment activity to customer accounts, deposit funds, as required, in GENUITY
bank accounts, research and resolve any payment posting errors and process
returned items from banks or other financial institutions

7.1   CSI will:

7.1.1 Process on a daily basis any customer payments received by CSI. This
      processing will include the allocation of payment data to the appropriate
      customer account and the transmission of payment data to the applicable
      customer account database.

7.1.2 Perform balancing and control processes to ensure all payment data
      transmitted to the billing systems are accepted and processed. CSI will be
      responsible for resolving all out of balance conditions.

7.1.3 Deposit, on a daily basis, any funds it receives in the designated GENUITY
      bank accounts. CSI will provide to GENUITY, monthly reports of bank
      deposit activity.

7.1.4 Investigate and make any required adjustments to a customer's account as
      the result of payment processing errors or as a result of returned items
      from banks or other financial institutions.

7.1.5 Perform balancing and control processes to ensure all payment data
      transmitted from external parties are accepted and processed to the CSI
      billing systems. External parties may include a lockbox processor, a
      credit card processor, electronic funds transfer or electronic data
      interexchange. CSI will manage the resolution of any out of balance
      conditions.

                                       9
<PAGE>

7.2   GENUITY will be responsible for defining performance standards,
      negotiating pricing, and managing the relationships between its lock box
      and credit card providers. Fees for these services will be directly billed
      from the providers to GENUITY.

Section 8.0 - Administration of Billing Capabilities

8.0   The administration of billing capabilities includes those activities
necessary to assure the billing systems used by CSI to bill GENUITY customer's
are maintained and supported to assure that billings reflect the correct rates,
terms, prices and conditions for GENUITY's products and services

8.1   CSI will, in accordance with GENUITY's policies, procedures and at
GENUITY's direction:

8.1.1 Administer, develop and implement changes to its billing systems in
support of objectives established by GENUITY for billing its customers,
including development of billing functionality to support new products and
services as identified by GENUITY.

8.1.3 Provide assessment of current and new billing capabilities and identify
      alternative billing solutions to meet GENUITY's billing requirements.

8.1.4 Administer and update billing system tables and business rules with
      product and service changes requested by GENUITY as outline in Schedule
      D - Change Request Procedures.

8.1.5 Perform user acceptance testing on behalf on GENUITY to ensure system
      and/or table driven changes accurately reflect the intended changes to
      GENUITY products and services and that such changes do not adversely
      impact billing production. CSI will manage the resolution of error
      conditions noted through testing.

8.1.6 Control, resolve and eliminate the cause of problems that occur due to CSI
      caused errors in billing systems or processes.

8.1.7 Refer to GENUITY for investigation and resolution, errors detected in the
      billing process that are due to systems or processes performed or
      maintained by GENUITY, e.g. ordering and provisioning errors.

8.1.8 GENUITY and CSI agree to provide the necessary systems interfaces and
      connections for the transfer of customer account, product and service,
      billing and financial data between CSI maintained billing systems and
      GENUITY maintained

                                      10
<PAGE>

      systems including, but are not limited to sales/order entry systems,
      pending order activity, provisioning, trouble reporting systems.

8.2   GENUITY will:

8.2.1 Define changes to existing products and services and requirements for new
      products and services in accordance with Change Request Procedures
      outlined in Schedule D, including the definition of business requirements
      and testing data.

8.2.2 Provide subject matter experts to answer questions and define test
      scenarios.

                                      11
<PAGE>

                                                                   ATTACHMENT 4B

                                  Schedule B
                     Billing Services Performance Measures

CSI and GENUITY agree to jointly define and establish a detailed action plan to
develop metrics that measure the effectiveness of the overall billing process
and compliance with the Billing Services business policies and procedures
established by GENUITY ("Action Plan") within sixty (60) days following the
effective date of this agreement. The Action Plan, will provide a mechanism to
establish guidelines ("Guidelines")based on performance metrics agreed upon by
the parties in accordance with the SOW and Transition Agreement. The Guidelines
will become effective upon the effective date of the renewal term, if any.
Included in the operating metrics will be measurements associated with the
services performed by CSI, as described in Schedule A-Description of Services,
as well as measures associated with the functions performed by GENUITY which are
an integral part of the total billing process, including but not limited to
usage polling and collection and provisioning timeliness.

Operating and compliance metrics will be defined and established relating to
billing timeliness and accuracy and credit and collections performance. CSI and
GENUITY agree to use the initial term of this agreement to establish threshold
levels of performance by CSI related to the metrics identified, and to establish
remedies to address CSI's inability to meet such performance levels in future
terms. The parties agree that assessment of actual performance against agreed
upon threshold levels, as well as implementation of the foregoing remedy
structure will begin in the renewal term, if any, of this agreement.

The Metrics established will be in substantially the form attached hereto.
Performance will be measured on a monthly basis, from the 1st through the 31st.
Metrics will exclude any jointly agreed upon holidays during which the defined
billing services may not be performed. Any variance from these performance
measures will be described in writing with actions identified to bring
performance to the agreed upon level.

                                       1
<PAGE>

                                                                   ATTACHMENT 4C

                                  Schedule C
                    Products and Services Currently Billed
                          by CSI on Behalf of GENUITY

The following list represents those products and services that are currently
billed by CSI on behalf of GENUITY. CSI has established system and process
capabilities that support the billing for these products and services.

Any new products and services or any modifications to the billing for the
products and services outlined below will require changes to the current billing
systems and processes used by CSI. For any new products and services or
modifications, GENUITY will submit a request for change to CSI in accordance
with Schedule D, Change Request Procedures. CSI will evaluate the requested
change and provide to GENUITY a written estimate of the cost and timeframes
associated with the change as outlined in Schedule D.

Products Billed:                            Web Advantage
@Vault                                      Web Hosting
ADSL
ATM PVC
BizConnect
Custom Hosting
Dialinx
Digital Subscriber
Ecache
Frame Relay
GNI Colocation
International ISP
Internet Advantage
Internet Advantage International
Internet Call Manager
Internet Server
IP Fax
ISP Direct
Managed Messaging
Private Line
Security Advantage
Site Patrol
Site Patrol International
Unified Messaging
Virtual Internet Service
Virtual Private Network
Voice Over IP
VPN International

                                    Page 1
<PAGE>

                                                                 ATTACHMENT 4D

                                  Schedule D
                           Change Request Procedures

1.0  Change request procedures to modify CSI's billing system or subprocess
     support systems are initiated through a written Change Request (CR).

2.0  A high level estimate of the Time and Cost (T&C) for changes the CSI
     systems or processes (order of magnitude) may be requested through the
     CHANGE REQUEST process. An order of magnitude may also be requested at the
     early stages of product or service development (GENUITY's PDMM or PD&L
     processes) to project anticipated costs and roll-out schedules. Order of
     magnitude estimates are not binding and will be estimated at CSI's
     discretion. Should GENUITY wish to pursue implementation of the change
     proposed in the order of magnitude, GENUITY shall issue a formal request
     for a T&C estimate as outlined in Section 3.0.

3.0  GENUITY may request a T&C estimate by submitting a T&C CHANGE REQUEST form
     to CSI's Change Control Manager. CSI will normally respond to GENUITY's
     request for an estimate within five (5) Business Days of receipt for table
     changes, ten (10) Business Days for pricing or contract changes and thirty
     (30) Business Days for new development. CSI's response will include the
     cost for development and implementation activities, an estimate of any new
     recurring charges, the implementation date, and all assumptions and/or
     deviations from GENUITY's specifications. This shall be a binding
     commitment from CSI to deliver the requested functionality at the stated
     price and on the stated date except as noted in Section 11.0 of this
     Attachment. For complex requests for new development a detailed break-out
     of the cost by functionality may be requested by GENUITY.

          3.1  All T&C CHANGE REQUEST responses shall include a listing of any
               new or increased recurring billing functional or data processing
               charges that shall apply. All recurring charges will require
               written authorization by GENUITY prior to development and
               implementation of the T&C CHANGE REQUEST.

          3.2  In the event this information is unavailable on the day the T&C
               CHANGE REQUEST quote is rendered to GENUITY, CSI will state in
               the quote that the recurring rate will be provided at a later
               date or a date to be negotiated between the Parties.

          3.3  If a request is considered by CSI to be too complex to meet the
               specified time requirement, or the information contained in the
               request is deemed insufficient, CSI shall notify GENUITY within
               fifteen (15) Business Days of receipt of original request and the
               Parties shall
<PAGE>

               negotiate a new response date for CSI's T&C CHANGE REQUEST quote.

          3.4  Upon agreement on the cost and implementation dates, the
               originator of the T&C CHANGE REQUEST or GENUITY's executive
               management will issue to CSI a formal authorization, in writing,
               authorizing the entire quote or option selected, if applicable.
               In the event that such authorization is received via e-mail or
               Internet, GENUITY hereby releases CSI from any and all liability
               to confirm the authenticity of the authorizing party or to
               otherwise validate the authority of the record's originator to
               authorize CSI to proceed with the development work.

4.0  GENUITY shall respond to CSI's requests for clarification of a change
     request or for requests for additional information in a timely manner.
     During the time period that questions pertaining to pending change request
     are outstanding, the T&C CHANGE REQUEST will be considered on hold by CSI.
     Once all questions are completely satisfied by the Parties, the project
     status will change to "Active/in Progress." Any delays in receipt of
     clarification or additional information requested may impact the delivery
     date of CSI's response and/or implementation date. CSI will advise the
     originator of the order regarding these delays.

5.0  GENUITY may issue a T&C CHANGE REQUEST to CSI to immediately commence work
     on the project by preauthorizing a portion of the total cost of the
     project.

          5.1  Once the entire quote has been issued by CSI, GENUITY must
               respond within ten (10) Business Days to authorize CSI to
               continue and complete the project. If full authorization has not
               been received, CSI may cease further project development when the
               preauthorized funded amount has been exhausted.

          5.2  If CSI ceases development of a T&C CHANGE REQUEST due to a delay
               in obtaining GENUITY's authorization or clarifications, the
               quoted costs and implementation date may be impacted.

6.0  All communications with GENUITY (written or oral) will be coordinated
     through the originator of the change request. All changes to the
     specifications of the requirement or interpretation of the specifications
     shall be in writing. GENUITY shall make available to CSI for each T&C
     CHANGE REQUEST an individual knowledgeable in all aspects of the CHANCE
     REQUEST with whom the assigned CSI counterpart may discuss project design
     and details in depth.

                                       2
<PAGE>

7.0  GENUITY shall notify CSI within ten (10) Business Days of the date of the
     T&C CHANGE REQUEST estimate whether the proposed estimate is accepted or
     rejected. The CHANGE REQUEST will be automatically rejected upon the
     expiration of ten (10) Business Days and no further communication is
     required for a rejected estimate. Where GENUITY is unable to meet the ten
     (10) Business Day requirement, GENUITY will notify CSI and the Parties will
     agree upon a new date. If GENUITY fails to notify CSI within twenty (20)
     Business Days of the acceptance or rejection of the T&C CHANGE REQUEST
     estimate, the estimate will be null and void and the T&C CHANGE REQUEST
     shall be considered void and CSI will notify GENUITY in writing of the
     canceled status.

8.0  GENUITY has the right to request a reconsideration when the T&C CHANGE
     REQUEST estimate from CSI that does not meet GENUITY's requirements or
     expectations. GENUITY shall notify CSI within ten (10) Business Days that a
     reconsideration is necessary. CSI agrees to discuss the basis for the
     estimate with GENUITY.

9.0  Any new recurring charges must be approved by GENUITY and by CSI and shall
     be included in the Agreement via a written amendment.

10.0 If GENUITY cancels an authorized or preauthorized request after receipt by
     CSI, GENUITY shall compensate CSI for all work completed prior to
     cancellation and for any efforts required to remove system functionality
     from code libraries. Within thirty (30) Business Days following
     notification of cancellation, CSI will send written notice to GENUITY
     regarding the amount owed by GENUITY, which shall be due upon receipt of
     such notice by GENUITY.

11.0 For T&C CHANGE REQUEST changes, unless otherwise agreed, CSI shall complete
     implementation by the agreed upon date stated in the quote. CSI shall use
     reasonable efforts to notify GENUITY if the scheduled implementation date
     will be in jeopardy. If an agreed upon implementation date is missed, CSI
     shall orally notify GENUITY as soon as possible. CSI shall provide written
     notification to GENUITY of its new implementation date within five (5)
     Business Days.

12.0 If following CSI's commitment pursuant to Section 3.0, requested
     functionality is not correctly implemented, by the agreed upon date, and
     has affected GENUITY's Customer's' bills, GENUITY's sole remedy shall be as
     follows:

          12.1 CSI will make credit adjustments to the Customer's bills if
               required

     If the cause of the incorrect functionality is due to incomplete or
     inaccurate requirements by GENUITY or from GENUITY's sign off on incomplete
     or

                                      3
<PAGE>

     inaccurate requirements or test results, CSI will not be held responsible
     for incorrect bills issued to customers. GENUITY will be responsible for
     any additional costs necessary for correcting the inaccuracies.

13.0 GENUITY will provide in the initial T&C CHANGE REQUEST user acceptance test
     criteria that will be used by CSI during user acceptance testing and will
     specify if a test bill is required prior to implementing the changes. If
     requested, and provided that GENUITY has authorized or preauthorized
     development, CSI will use reasonable efforts to provide a test bill sample
     to GENUITY. GENUITY agrees to validate the accuracy of the requested
     changes and provide concurrence to CSI in writing within five (5) Business
     Days or prior to the first mail date if less than five (5) days. GENUITY
     shall hold CSI harmless from any liability for billing errors that may
     result from the requested changes.

14.0 GENUITY will note in the initial T&C CHANGE REQUEST if a post
     implementation bill sample is required.

15.0 CSI shall notify GENUITY within ten (10) Business Days after
     implementation that all work has been completed or procedures are in place.

CSI shall begin to bill GENUITY at the time the estimate is authorized and
development work has begun. The payment schedule will be based upon work
incurred in a given month. Notwithstanding the foregoing, CSI shall have the
option, based on a credit review of GENUITY or CSI policies and procedures, to
require prepayment of CHANGE REQUEST

                                       4
<PAGE>

                                                                   ATTACHMENT 4E

                                  Schedule E
                               ARBOR Conversion

At the time of this agreement CSI and GENUITY are jointly involved in converting
from GENUITY's Oracle Billing platform to CSI's Kenan ARBOR billing platform
("Arbor Platform").  GENUITY AND CSI agree that this project is of strategic
importance to GENUITY and commit to completion of this project as outlined in
this Schedule E.

Overall funding for this conversion is the responsibility of CSI and the overall
conversion project ("Conversion Project") will be managed by CSI.

A detailed implementation plan exists to migrate GENUITY's current customer base
from Oracle to the Arbor Platform, develop new usage based mediation and rating
processes, and to write the business rules in support of GENUITY's products and
services to be billed by CSI from the ARBOR Platform. The Arbor Conversion
project will go to production in the third quarter 2000 and will be complete by
12/12/2000 when post Arbor Conversion activities are completed.

The project plan requires GENUITY resources, cooperation and support to
accomplish the Arbor Conversion and the parties will each contribute personnel
to accomplish the Arbor Conversion ("Conversion Team") Arbor Conversion
activities of the parties will include but are not limited to:

GENUITY will:

1.   work with CSI First Rate team to ensure the various data collectors will
     pass the required usage data to First Rate for mediation to ARBOR.

2.   work with the CSI Conversion Team to provide the necessary customer data
     from the Oracle legacy system to be migrated to ARBOR.

3.   provide a full time representative to the Conversion Team.

4.   will continue to participate on the Conversion Team to ensure that the
     Conversion Team is current on all changes implemented in the interim.

5.   GENUITY Data Control will continue to participate on the Conversion Team to
     ensure all price book changes are communicated to the Conversion Team.

CSI will:

1.   work with GENUITY to provide a detailed migration approach and plan that
     encompasses all required tasks to complete the Oracle Financials to Arbor
     conversion as it pertains to usage mediation and billing.

                                       1
<PAGE>

2.   work with GENUITY to model all products within the Arbor 9.1 Billing
     instance to meet the previously defined requirements.

3.   work with GENUITY to develop an end-to-end set of test criteria and scripts
     to perform a comprehensive test of the conversion and ensure billing
     accuracy once conversion occurs.

4.   design, develop, and provide all required interfaces to handle usage
     mediation, general ledger, bill distribution, bill formatting, taxing,
     commissions, compensation, data warehouse, reseller billing, payments, and
     collections.

5.   continue to work with GENUITY to develop all processes, teams, and
     practices required to provide the core billing functions of data
     accumulation, bill processing, bill format and distribution, inquiry and
     investigation, credit verification, collections, and payment processing
     evolving out of this conversion.

There may be other activities identified as the Conversion Team moves through
the project. GENUITY will support these activities as identified.

The Arbor Conversion Project plan calls for the Oracle/bp databases to be
available through 2003, as historical data contained in these databases will not
be converted. CSI may require access to the Oracle/bp database history for
resolution of billing inquiries and referrals. GENUITY agrees to maintain and
support the Oracle/bp historical databases thorough year-end 2003.

CSI will manage the ARBOR Conversion Project per the current schedule and will
engage other resources or affiliates as necessary. Status reporting will
continue as it exists today, as will the Core Team and the Executive Team.
GENUITY, GENUITY AND CSI commit to continued executive representation on these
teams.

                                       2
<PAGE>

                                                                   ATTACHMENT 4F

                                  Schedule F
                       Agreement to Support Continuation
                                      of
                  ATM SVC Usage Based Billing Implementation

At the time of this agreement CSI and GENUITY are jointly involved in
implementing ATM SVC Usage Based Billing on the Kenan ARBOR billing platform.
GENUITY AND CSI agree that this project is of strategic importance to GENUITY
and commit to completion of this project as outlined in this agreement.

Overall funding for this project is being managed by GENUITY.  GENUITY will
reimburse CSI for project work performed by CSI or CSI's subcontractors as
defined in the ATM SVC SOW.  CSI will as required by GENUITY, provide support
for expenses for which they are requesting reimbursement.

A project plan exists to develop functional and system requirements, system
designs, new mediation and rating processes and to code, test and put into
production the ATM SVC UBB product on the ARBOR platform in support of GENUITY's
business requirements. The project will go to production in the late second or
early third quarter 2000 and will be complete by 12/12/2000 when post conversion
activities are completed.

The project plan requires GENUITY and CSI resources and support.  Development
project activities identified to date are:

1.   GENUITY will continue to work with the CSI ATM SVC UBB Project Team to:

     .    complete the project requirements and designs for the ATM SVC UBB
     product
     .    cooperate in the design and implementation of business processes to
     provide necessary account, service instance, product, rate change, and
     error correction information
     .    participate in the integration and User Acceptance Testing and to
     participate in the roll out of the ATM SVC UBB product.

2.   GENUITY will work with CSI First Rate team to ensure that the Ascend ATM
     Accounting Server data collectors will pass the necessary usage data to
     First Rate for mediation to ARBOR.

3.   GENUITY will work with the CSI Billing Production Team to provide the
     necessary billing information for input into ARBOR. This information
     includes but is not limited to account, service instance and product
     information for new ATM SVC UBB customers and adds, changes and deletions
     for existing ATM SVC UBB customers.

                                       1
<PAGE>

4.   GENUITY will work with CSI Billing Change Management team to provide
     information on all new ATM SVC UBB products and rate changes.

There may be other activities identified as the Project Team moves through the
project.  GENUITY will support these activities.

Post conversion activities also require GENUITY and CSI resources and support.
Post conversion, "in production" activities identified include:

GENUITY:

1.   manage the Ascend Accounting Servers and is responsible for providing CSI
     with ATM SVC usage records on a daily basis.

2.   provide CSI with account, service instance and product information for both
     new customers and changes to existing customers ATM SVC services so that
     the information can be input to the ARBOR billing platform.

3.   provide CSI with new ATM SVC UBB product updates and rate changes so that
     the information can be input to the ARBOR billing platform.

4.   work with CSI to resolve errors involving account information, usage
     guiding errors and rating errors.

CSI will:

1.   provide a detailed deployment approach and plan that encompasses all
     required tasks to complete the ATM SVC product rollout as it pertains to
     usage mediation and billing.

2.   work with GENUITY to model all features of the ATM SVC product, and
     proposed account structures within the Arbor Billing system to meet GENUITY
     requirements.

3.   work with GENUITY to develop and execute an end-to-end set of test scripts
     to perform a comprehensive test of the ATM SVC product.

4.   CSI will develop and build rate tables to accommodate the ATM SVC usage
     pricing CSI will provide fast path rate changes for ATM SVC as necessary.

There may be other ongoing production activities identified as the Project Team
moves into implementation.  GENUITY will support these activities.

                                       2
<PAGE>

CSI will manage the ARBOR ATM SVC UBB implementation per the current schedule
and will engage other resources or affiliates as necessary. Reporting and
participation on ATM PDMM teams will continue as it exists with representation
from GENUITY and CSI.

                                       3
<PAGE>

                                                                   ATTACHMENT 4G

                                  Schedule G
                          Billing Services Agreement
                                Services Prices

The following charges for the Services provided under this Agreement are
effective during the Term of the Agreement as specified in Section 5 of the
Agreement. Invoicing will be handled on a monthly basis.

Section 1 - Data Accumulation

1.1  Event Management, Data Accumulation, Usage Processing, Mediation:

     1.1.1 Event Management hourly rate                                   $56.00
           Charge per man hour worked to balance and control
           usage, work errors, resolve billing issues, etc.

     1.1.2 UAT Testing (per month)                                     $1,950.00
           Routine UAT testing of the Event Management Platform
           *Subject to change based on new Program Implementations
           (Change Requests)

Section 2 - Bill Processing

2.1  Usage Processing (Arbor Message Processing System), Billing:
     Charge to balance and control Usage, work MIU errors,
     resolve guide file issues, resolve billing usage issues,
     monitor the usage billing schedule and performance, etc.

     2.1.1 Less than 10,000,001 messages per month                    $19,000.00
     2.1.2 Between 10,000,001 and 15,000,000 messages per month       $28,000.00
     2.1.3 Between 15,000,001 and 20,000,000 messages per month       $36,000.00
     2.1.4 Between 20,000,001 and 30,000,000 messages per month       $49,500.00
     2.1.5 Between 30,000,001 and 40,000,000 messages per month       $60.500.00
     2.1.6 Between 40,000,001 and 60,000,000 messages per month       $76,500.00
     2.1.7 Between 60,000,001 and 80,000,000 messages per month       $89,500.00
     2.1.8 Above 80,000,001 per incremental 20M messages per month    $11,000.00

2.2  Process Data:

     2.2.1 Process Data production support (per month)               $192,500.00
           Balancing and controls, Error queue management

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           Tracking and correction, Bill review and investigation,
           Order entry.
           *Subject to change based on new Program Implementations (Change
           Requests)

Section 3 - Bill Format and Distribution

3.1  Bill Format:

     3.1.1 Format tool support (per month)                            $11,000.00
           Infrastructure support of the format tool:
           -Manage the requirements and/or defects of the Arbor IDesign
           product, which includes working with vendor and business owner.
           -Manage installation of IDesign vendor release/patch installs
           on NBO
Tampa hardware.
           -Work with IT to implement any Arbor billing system impacts with an
IGEN release.
           -Identify embedded base template impacts resulting from new vendor
release installs.
           -Work with IT on IGEN and IDesign processing and distribution
           requirements for IDesign environments (unit test, UAT, production).
           -Manage the distribution and installation of all format templates.
           -Develop and maintain unit test tools.

     3.1.2 Bill Format changes
                            (Included with Program Implementation Quote)

3.2  Bill Distribution:

     3.2.1 Distribute via Paper - Bill Stock
           Charge for bill stock branded with any logo (digitized)    $.033/page

           Charge for 9x12 remittance envelope branded with:
           One Color Logo                                         $.185/envelope
           Two Color Logo                                         $.218/envelope
           Three Color Logo                                       $.277/envelope

           Charge for 9x12 expansion specialty envelopes (1" and 2") with:
           One or Two Color Logo                                  $2.09/envelope
           Three Color Logo                                       $2.31/envelope

           BSS (Oracle platform) Charge for form & envelope        $0.21/invoice

     3.2.2 Distribute via Paper - Postage                            As Incurred
           Rate charged will be actual incurred cost.

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           Current (2/00) average number of pages per bill is as follows:
           GNI - 6 pages
           Telecom - 13 pages (mail out 3 copies)
           VOIP - 8-10 pages

     3.2.3 Alternate Media (Electronic, CD-Rom, Diskette)(Pricing available upon
           request)

     3.2.4 Electronic Bill Presentation and Payment (Pricing available upon
           request)
3.3  Bill Distribution - Misc. Charges (Rates are per month per invoice)
     Labor and warehousing costs associated with  Bill Distribution
           GNI                                                             $2.76
           Telecom                                                         $1.02
           VOIP                                                            $6.73
           BSS                                                             $0.34

3.4  Bill Distribution - Additional Services:

     3.4.1 Bill Message Page charge                        Individual case basis

     3.4.2 Bill Insert charge                              Individual case basis

     3.4.3 Direct Mail charge                              Individual case basis

     3.4.4 Marketing Message / Bill Phrase charge          Individual case basis

Section 4 - Inquiry and Investigation

4.1  Administrative - No research required (per contact)                  $11.25
     Name/Address changes, information requests

4.2  Request for second copy of bill (per contact)                         $9.25
     Includes costs for bill stock and postage

4.3  Error resolution (per initial contact)                              $210.00
     Charge to investigate complaint, document
     findings and resolve issue (including charge for adjustment)

Section 5 - Credit Verification

5.1  Domestic customer credit agency fee                                  $27.50
     Charge per customer reviewed to access
     credit history via credit agency reports.

5.2  International customer credit agency fee                            $192.50

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<PAGE>

     Charge per customer reviewed to access
     credit history via credit agency reports.

5.3  Customer credit research charge                                     $290.50
     Charge per customer reviewed to analyze
     worthiness and provide recommendation.

Section 6 - Collections Management

6.1  Treatment

     6.1.1 Per account in A/R Aging (31 - 60 days)                        $48.50

     6.1.2 Per account in A/R Aging (61 - 90 days)                        $48.50

     6.1.3 Per account in A/R Aging (greater than 90 days)                $48.50

6.2  Collections

     6.2.1 Per account recovered                                          $56.00
           Customer's account updated to reflect payment
           (OCA fees will be deducted from gross amount collected)

Section 7 - Payment Processing

7.1  Payment processing costs per invoice processed                        $4.45
     Charges to post customer payments, reconcile lockbox
     receipts, work LIU errors, perform investigations,
     deposit funds into company official bank accounts.

7.2  Returned check - processing (per item)                               $25.00
     Customer's account and credit rating updated

Section 8 - Manage Billing Capabilities

8.1  Baseline routine changes (per month)                            $189,500.00
     Covers up to 2,200 man hours per month of routine
     requests for changes to GTE's billing system
     (i.e. table changes for pricing updates) and production
     of routine reports required by the business.

8.2  Additional routine changes rate per hour                             $76.00
     Charge applies for routine requests for changes
     beyond the baseline amount.

8.3  Program Management Consultation rate per hour          126.00 (plus travel)

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     Charge applies for general consultative activities.

8.4  Program Implementation lump sum charge     (Pricing available upon request)
     One-time non-recurring charge for a program implementation
     and / or change request associated with a specific project
     beyond activities defined in this schedule.

Section 9 - IT Costs

9.1  First Rate Continuing Operations (COPS) Maintenance - per hour       $85.00

9.2  First Rate Continuing Operations (COPS) Production support - per
     hour                                                                 $85.00

9.3  First Rate License Fee (per month)                                $4,167.00

9.4  First Rate AM/FM (per month)                                       3,583.00
     Recovery of hardware costs (i.e. servers)

9.5  Arbor Continuing Operations (COPS) Maintenance - per hour            $85.00

9.6  Arbor Continuing Operations (COPS) Production support - per hour     $85.00

9.7  Arbor AM/FM (per month)                                          100,000.00
     Recovery of hardware costs (i.e. servers)

Section 10 - Miscellaneous Charges

10.1 General Consultative - per hour                                     $126.00

10.2 Mileage charge                                                        $0.33
     General mileage charge for all travel over 25 miles one-way

10.3 Expenses                                                        As Incurred
     Meals, lodging, etc. associated with travel

10.4 Data Security (per month)                                        $12,000.00
     Support and Monitor/Control access to GENUITY and CSI
     Instances of ARBOR

10.5 Arbor License Fee - CSI costs - (per month)                     $147,000.00

10.6 Arbor License Maintenance Fee first instance (per month)         $85,500.00
     Arbor License Maintenance Fee - per additional instance (per
     month)                                                           $18,300.00

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<TABLE>
<S>                                                                     <C>
10.7  Vertex software fee for tax application (per month)                 $4,400.00

10.8  GTE Software license and maintenance fee (per month)              $56,000.000

10.9  Tax Dept matrix clean-up, system testing, project driven tasks
      (per hour)                                                             $60.00

10.10 Tax Dept on going support, change control & training (per month)      $600.00

Section 11 - Minimum Monthly Charge

11.1 Minimum monthly charge for service rendered under this agreement   $350,000.00
</TABLE>

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<PAGE>

                                                                   ATTACHMENT 4H

                                  Schedule H
                                 Tax Services

The "GTE" Tax Department will perform the necessary tax research and other
services as required to provide on-going support for "GENUITY" billing
environment with related tax application matrices, change control, one-time
system testing and training.

I.   Services

Tax Billing Matrix
------------------

Ongoing support includes determining the local, state and federal taxation rates
of new products and services, utilizing the "GTE" tax billing matrix as the
primary source ("Tax Services"). The Tax Billing Matrix will be the long-term
solution as the vehicle used to determine the tax rates of products and
Services. The Tax Billing Matrix will interface with the Arbor Billing System
within the term of the Billing and Collection SOW. The "GTE" Tax Department will
provide updates, changes, and corrections as required to the Tax Billing Matrix.
The interim method of communicating taxation rates of products and services will
be via email between CSI, GENUITY and GTE Tax Department.

Not included as a part of this Tax Billing Matrix services are: contract
reviews, projects such as nexus requirements, prototype design interaction,
products/services rollout implementation process, etc.

Change Control
--------------

The introduction of new products and services will be incorporated with the
product standardization process with direct interaction from GENUITY product
managers.

The update of tax rates will continue to be handled by CSI.

System Testing
--------------

System Testing includes auditing tables and functionality requirements for
existing and future GENUITY companies.  In addition, report writing
functionality will be tested as required for tax compliance and other ad-hoc
reports.

II.  PRICING

The Tax Services set forth herein will be provided at $600.00 per month.

System Testing and other project driven tasks will be provided at $60.00 per
hour.

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<PAGE>

III. TAX LIABILITY

GENUITY shall be liable for all applicable sales, use or similar taxes for
amounts invoiced to GENUITY's customers and GENUITY shall be responsible for
preparation and filing of all tax returns and applicable tax reporting to all
taxing jurisdictions. Taxes shall be added to each customer's invoice, however,
GTE's Tax Department and/or CSI shall not be liable for miscalculation or
omissions with regard to such taxes.

IV.  TERMINATION

From September 1, 2000 through the end of the Initial Term, upon thirty days
written notice, either party may terminate this Schedule H without liability.

                                       2

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