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                                                                   EXHIBIT 10.31

                                MASTER AGREEMENT

                                 BY AND BETWEEN

                             WINSTAR WIRELESS, INC.

                                       AND

                                  WAM!NET INC.


         This Master Agreement is entered into as of the 31st day of December,
1999 (the "Effective Date") by and between WINSTAR WIRELESS, INC., a Delaware
corporation, with offices located at 7799 Leesburg Pike, Suite 700 South, Tysons
Corner, VA 22043 ("Winstar"), and WAM!NET INC., a corporation organized under
the laws of Minnesota, with offices located at 655 Lone Oak Drive, Eagan, MN
55121 ("Wam!Net").


                              EXPLANATORY STATEMENT
                              ---------------------

         Wam!Net desires to acquire from Winstar certain network facilities,
connectivity and Capacity. Winstar is willing to provide Wam!Net with such
network facilities, connectivity and Capacity, on the terms and conditions set
forth herein.

1. Definitions

         1.1 Certain Definitions.

                  (a) "Affiliate" shall mean, with respect to any entity, any
         other entity Controlling, Controlled by or under common Control with
         such entity, whether directly or indirectly through one or more
         intermediaries.

                  (b) "Agreement" means this Master Agreement.

                  (c) "Business Day" means any day on which Citibank, N.A. is
         open for the transaction of banking business.

                  (d) "Capacity" shall mean the digital transmission capability
         of a given portion of the Winstar Network designed to transmit digital
         signals at a stated rate. Capacity is designated in industry standard
         measurements such as OC-3, DS-3, T-1 etc.

                  (e) "Confidential Information" means all information, in any
         form, furnished or made available directly or indirectly by one Party
         (the "Disclosing Party") to the other (the "Receiving Party") that (i)
         concerns the operations, affairs or businesses of the Disclosing Party,
         the financial affairs of the Disclosing Party, or the relations of

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         the Disclosing Party with its customers, employees or service
         providers, and (ii) is marked confidential, restricted, proprietary, or
         with a similar designation or (iii) is provided during or created for
         the Build-out Process. "Confidential Information" excludes any
         particular information that the Receiving Party can demonstrate:

                           (i) at the time of disclosure, was in the public
                  domain or in the possession of the Receiving Party;

                           (ii) is published or otherwise becomes part of the
                  public domain other than by the unauthorized disclosure by the
                  Receiving Party;

                           (iii) was received after disclosure from a third
                  party who had a lawful right to disclose such information to
                  the Receiving Party without any obligation to restrict its
                  further use or disclosure; or

                           (iv) was independently developed by the Receiving
                  Party without reference to Confidential Information of the
                  Disclosing Party.

                  (f) "Control" and its derivatives shall mean legal, beneficial
         or equitable ownership, directly or indirectly, of more than fifty
         percent (50%) of the outstanding voting capital stock (or other
         ownership interest, if not a corporation) of an entity, or actual
         managerial or operational control over such entity.

                  (g) "Days" or "days" shall mean calendar days unless otherwise
         specified.

                  (h) "Deferred Payments" shall have the meaning set forth in
         Schedule 1.

                  (i) "Down Payment" shall mean Twenty Million and 00/100
         Dollars ($20,000,000.00).

                  (j) "DS-3" shall mean a quantity of Capacity comprising a
         digital circuit (fiber or spectrum) capable of transporting signals at
         a speed of approximately 45 Mbps.

                  (k) "Effective Date" has the meaning set forth in the preamble
         to this Agreement.

                  (l) "Eligible Location" shall mean a building designated by
         Wam!Net at which a Wam!Net customer is located that meets all of the
         following criteria: (i) it is within the reliable radio range of a
         then-existing Winstar hub; (ii) it has verified (or creatable, with
         good faith efforts by Winstar), line of sight without frequency
         interference; (iii) the site has been visited by Winstar personnel or
         otherwise verified as, in Winstar's reasonable opinion, able to be
         built-out utilizing outdoor unit space, power, security, verified riser
         and any other necessary build-out elements; and (iv) Winstar has or may
         acquire all necessary roof rights.

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                  (m) "Equipment" shall mean the equipment provided by Winstar
         to Wam!Net pursuant to Schedule B.

                  (n) "Events of Default" shall mean each of the following:

                           (i) any representation or warranty made by a Party in
                  the Transaction Documents shall prove to have been incorrect
                  when made in any respect which could reasonably be expected to
                  have a material adverse effect upon the other Party's ability
                  to realize the benefits of the Transaction Documents;

                           (ii) a Party commits a material breach of the
                  Transaction Documents that is capable of being cured on
                  commercially reasonable terms within thirty (30) days, which
                  breach is not cured within thirty (30) days after notice of
                  breach to the breaching Party, or

                           (iii) a Party commits a material breach of the
                  Transaction Documents that is not capable of being cured
                  within thirty (30) days and the breaching Party fails to (a)
                  proceed promptly and diligently after written notice to
                  correct the breach, (b) develop within fifteen (15) days
                  following written notice of breach a complete plan for curing
                  the breach, and (c) cure the breach within sixty (60) days of
                  notice thereof.

                  (o) "FCC Licenses" shall have the meaning set forth in Section
         5.1(b).

                  (p) "Installed Equipment" shall mean equipment owned by
         Wam!Net used on the Winstar Network.

                  (q) "Intercity Backbone" shall mean the long haul backbone
         network used by Winstar to provide Capacity pursuant to Schedule A.

                  (r) "Indefeasible Right of Use" or "IRU" shall mean an
         exclusive indefeasible right to use a specified amount of Capacity for
         a specified period.

                  (s) "Link" shall mean local access links, composed of radio
         pairs and backhaul facilities connecting an Eligible Location to a
         Winstar switch center.

                  (t) "Losses" shall mean all liabilities, damages and related
         costs and expenses (including fines, levies, assessments, reasonable
         legal fees and disbursements and costs of investigations, litigation,
         settlement, judgment, interest and penalties) directly incurred by a
         Party.

                  (u) "Network Control" shall mean (i) the unfettered use of all
         Network Facilities; (ii) day to day operation and control of the
         Network Facilities; (iii) determination and the carrying out of policy
         decisions, including the preparation and filing of applications with
         the Federal Communications Commission ("FCC") relating to the Network
         Facilities; (iv) employment, supervision, and dismissal of personnel

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         involved with the Network Facilities; (v) payment of financial
         obligations, including expenses arising out of operation involved with
         the Network Facilities; and (vi) the receipt of monies and profits
         derived from the operation of the Network Facilities.

                  (v) "Network Facilities" shall mean the Intercity Backbone,
         the Installed Equipment, and any other equipment and facilities used in
         providing Capacity and local connectivity on the Winstar Network
         pursuant to this Agreement, over which Winstar, as a FCC licensee, must
         retain control as that term is defined in the Communications Act of
         1934, as amended, and/or any applicable FCC rules or case law.

                  (w) "Notice of Election" shall have the meaning set forth in
         Section 12.4.

                  (x) "OC-3" shall mean a quantity of Capacity comprising a
         digital circuit (fiber or spectrum) capable of transporting signals at
         a speed of approximately 155 Mbps.

                  (y) "Party" shall mean Wam!Net or Winstar, individually, as
         appropriate.

                  (z) "Parties" shall mean Wam!Net and Winstar, collectively.

                  (aa) "Purchase Price" shall mean the sum of the Down Payment
         and the total principal amount of the Deferred Payments to be paid by
         Wam!Net to Winstar pursuant to Schedule 1.

                  (bb) "Security Interest" shall have the meaning set forth in
         Schedule 2.

                  (cc) "T-1" shall mean a quantity of Capacity comprising a
         digital circuit (fiber or spectrum) capable of transporting signals at
         a speed of approximately 1.544 Mbps.

                  (dd) "Term" shall have the meaning set forth in Section 3.

                  (ee) "Transaction Documents" shall mean the Agreement and all
         Schedules and Exhibits.

                  (ff) "Wam!Net" shall mean Wam!Net Inc.

                  (gg) "Winstar" shall mean Winstar Wireless, Inc.

                  (hh) "Winstar Network" shall mean the facilities-based
         telecommunications system over which Winstar offers telecommunications
         services to its subscribers to the extent that Winstar has an
         obligation to use the system to meet its obligations hereunder.

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         1.2 Other Definitions. Other terms used in this Agreement are defined
in the context in which they are used and have the meanings there stated.

2. Quarterly Meetings

         During the Term, Wam!Net and Winstar shall meet on a quarterly basis to
discuss their joint plans and objectives with respect to the development and
deployment of new e-business solutions and any issues which may arise related to
the performance of the Parties' obligations under the Transaction Documents.
Each Party will designate representatives from its areas of technical,
marketing, and senior management, to participate in each of the quarterly
meetings. The Parties shall develop a process for creating the quarterly agenda
for the quarterly meetings.

3. Term. Except as may otherwise be provided in a Schedule, the term of the
Transaction Documents shall begin upon the Effective Date and shall end on the
twentieth (20th) anniversary of the Acceptance Date of the first System Segment
that is Accepted pursuant to Schedule A (the "Term"), unless terminated earlier
in accordance with this Agreement.

4. Obligations of the Parties

         4.1 Intercity Backbone Capacity. Winstar shall sell to Wam!Net and
Wam!Net shall purchase from Winstar IRUs with respect to specified Capacity on
the Intercity Backbone pursuant to the terms and conditions in Schedule A.

         4.2 Equipment Sale. Winstar shall sell to Wam!Net and Wam!Net shall
purchase from Winstar the Equipment, pursuant to the terms and conditions in
Schedule B.

         4.3 Installation and Maintenance. Winstar shall sell and Wam!Net will
purchase certain local access connectivity, and certain support services,
pursuant to the terms and conditions in Schedule C.

         4.4 Collocation. Winstar shall sell and Wam!Net shall purchase
collocation and associated services, pursuant to the terms and conditions in
Schedule D.

         4.5 Joint Marketing. The Parties shall engage in joint marketing
activities, pursuant to the terms and conditions in Schedule E.

5. Covenants of the Parties

         5.1 Control.

                  (a) Winstar shall secure, at its own expense, all licenses,
         permits, agreements, consents, rights-of-way, and other arrangements
         necessary for: (i) the installation and operation of the Network
         Facilities, (ii) any other element of the Winstar

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         Network utilized by Winstar in meeting its obligations under the
         Transaction Documents, and (iii) Network Control of the Network
         Facilities. Winstar shall not be responsible (x) for such costs to the
         extent that Winstar, in its reasonable discretion, determines that such
         costs would exceed its standard cost guidelines for the geographic area
         involved by more than 20% or (y) for Wam!Net's internal costs incurred
         to make initial contact with building owners or managers to assist
         Winstar in acquiring the necessary roof rights.

                  (b) During the Term, each of the Parties shall at all times
         comply with FCC rules and regulations as well as all state and local
         regulations or requirements governing spectrum licenses owned by
         Winstar and used by Winstar to provide all connectivity pursuant to
         this Agreement ("FCC Licenses"), and the provision of
         telecommunications services hereunder, as all such rules, regulations,
         and requirements are applicable to such Parties' obligations under the
         Transaction Documents.

                  (c) Winstar shall retain Network Control and control over its
         FCC Licenses at all times during the Term of the Transaction Documents,
         and shall have, at all times therein unfettered access to all of the
         facilities where transmissions and receptions under its FCC Licenses
         are being conducted or controlled.

                  (d) Winstar will take all reasonable precautions not to
         disturb or interfere with Wam!Net's use of the Installed Equipment,
         Capacity, collocation, and local connectivity provided by Winstar under
         the Transaction Documents, unless such disturbance is deemed by Winstar
         to be necessary for Network Control and control over its FCC Licenses.

                  (e) During the Term, Wam!Net shall not represent itself as the
         holder of any of the FCC Licenses, nor as the representative of Winstar
         before the FCC, any state regulatory body or any other third party.

                  (f) Except as otherwise required by law, all filings made
         during the Term before regulatory bodies with respect to Winstar's FCC
         Licenses, including filings with respect to obtaining any licenses or
         approvals needed in connection with Winstar's obligations hereunder,
         shall be made by and in the name of Winstar. Wam!Net, at Winstar's
         expense, shall cooperate fully with Winstar in the making of such
         filings that are applicable to any Winstar obligations under the
         Transaction Documents.

                  (g) Wam!Net shall not take a position or issue a public
         statement with respect to regulatory or legislative issues that could
         be reasonably expected to adversely impact Winstar's business without
         first consulting with Winstar. Wam!Net will, at Winstar's expense,
         reasonably support Winstar's legislative and regulatory efforts with
         respect to ensuring nondiscriminatory access to buildings by
         telecommunications carriers, and, in no event, will take any position
         adverse to Winstar's positions on this matter.

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                  (h) Nothing in the Transaction Documents is intended to
         diminish or restrict Winstar's obligations as an FCC licensee and
         Winstar and Wam!Net desire that the Transaction Documents be in full
         compliance with (i) the terms and conditions of Winstar's FCC Licenses;
         (ii) all applicable rules and policies of the FCC; (iii) the
         Communications Act of 1934, as amended, and (iv) any other applicable
         federal, state and local law or regulation It is expressly understood
         by Winstar and Wam!Net that nothing in the Transaction Documents is
         intended to give Wam!Net any right which would be deemed to constitute
         a transfer of control (as `control' is defined in the Communications
         Act of 1934, as amended, and/or any applicable FCC rules or case law)
         of Winstar or of one or more of the FCC Licenses from Winstar to
         Wam!Net.

         5.2 Network Integrity.

                  (a) Subject to Section 5.1(d), neither Party may improperly
         restrict or interfere with the other Party's network or use of services
         by the other Party, its Affiliates, any other customer of either Party
         or any third party. Upon notice by a Party, the other Party shall
         promptly remove any hazard, interference or service obstruction that
         may be caused by hardware, software or connectivity that the notifying
         Party does not provide. Nothing stated herein shall be construed to
         interfere with a Party's ability to comply with the rules, regulations
         or directives of any governmental or jurisdictional authority.

                  (b) Winstar may, after giving Wam!Net notice, immediately
         suspend services under the Transaction Documents to Wam!Net in whole or
         part, without incurring any liability for such suspension, if Winstar
         in the exercise of reasonable discretion, determines that Wam!Net is or
         may utilize such services in a manner not contemplated by this
         Agreement that results in, or could result in (i) interference with the
         use of the Winstar Network, or any component thereof, by other parties;
         (ii) damage, interference, degradation or other adverse effects with
         respect to the proper functioning of the Winstar Network, or any
         component thereof, equipment or service; (iii) the fraudulent
         procurement of (1) any Network Facilities or other support services
         provided hereunder, or (2) of any other services utilizing the Winstar
         Network, or any component thereof; or (iv) a violation of the
         Communications Act of 1934, as amended, and/or any applicable FCC rules
         or case law. In the case of a suspension of service under Section
         5.2(b)(iii), Winstar shall give Wam!Net not less than twelve (12) hours
         notice. To the extent that any of the events set forth above are the
         result of any action by a Wam!Net customer, Wam!Net will, following
         notice from Winstar, suspend the service of the Wam!Net customer.

         5.3 Designation of Eligible Locations.

                  (a) Within fifteen (15) days of Wam!Net identifying a desired
         site to Winstar, Winstar shall provide Wam!Net with a determination as
         to whether the site is an Eligible Location. During such 15-day period,
         Winstar and Wam!Net will work together to allow Wam!Net to provide
         Winstar with a fully completed service request form in the event, and
         after, the site identified by Wam!Net is classified by Winstar as

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         an Eligible Location. Upon receipt of such service request form,
         Winstar will provide Wam!Net with a firm order committment, and will
         install the necessary equipment at the Eligible Location as promptly as
         practicable, but in no event more than sixty (60) days after receipt of
         such service request form.

                  (b) In determining whether a desired site is an Eligible
         Location, if Winstar reasonably determines that the cost of rooftop
         access and/or equipment installation will exceed its standard cost
         guidelines for the geographic area involved by not more than 20%,
         Winstar must offer Wam!Net the option to pay one-half of the amount in
         excess of Winstar's standard cost guidelines, and if Wam!Net so
         chooses, and subject to the site satisfying all other required criteria
         used in determining whether the site is an Eligible Location, the site
         shall be deemed an Eligible Location. If the costs would exceed such
         guidelines by more than 20%, Winstar may, in its sole discretion,
         choose not to designate such site as an Eligible Location.

         5.4 Access to Facilities. Both Parties shall provide the other Party's
personnel with access to its facilities to the extent reasonably required for
such Party to perform its obligations hereunder. Any such access permitted
hereunder shall be in accordance with each Party's applicable internal security
procedures, and any applicable FCC requirements.

         5.5 Future Winstar Network Build-out.

                  (a) Pursuant to Schedule C, during calendar year 2000, Winstar
         will, at Wam!Net's request, install and provide connectivity with at
         least 700 Links to Eligible Locations designated by Wam!Net.

                  (b) In determining whether a location is an Eligible Location
         or whether Winstar will build its network to certain geographic areas,
         Wam!Net shall be entitled to participate in the process by which
         Winstar determines its ultimate network build-out map ("Build-out
         Process").

                  (c) As part of the Build-out Process, Winstar will provide
         Wam!Net with existing and planned hub addresses, city identifications,
         switch addresses, delivery time frames, and construction status of
         already planned hub and central office addresses. Wam!Net will provide
         Winstar such information as Winstar reasonably requires to complete the
         Build-out Process. The information provided hereunder will be used to
         assess: (i) existing and planned overlay coverage; (ii) potential
         bandwidth required by Wam!Net's customers across all applications;
         (iii) bandwidth segmentation requirement required by Wam!Net's
         customers across all applications; (iv) strategy outcome planning; and
         (v) new product application deployment. Notwithstanding Wam!Net's
         participation in the Build-out Process, Winstar shall have the final
         determination with respect to identifying a building as an Eligible
         Location or extending its network to a certain geographic area.

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                  (d) Future Purchases. During the Term, for any additional
         purchases Wam!Net desires to make from Winstar, Winstar will provide
         Wam!Net with price and terms at least as favorable with regard to
         Winstar's percentage of profit over Winstar's costs for the purchase
         being priced as Wam!Net is receiving hereunder.

                  (e) In the event a Wam!Net designated node in one of the
         markets listed in Exhibit 1 of Schedule D has not been collocated with
         a Winstar switch center pursuant to Schedule D on the date a System
         Segment terminating in that market is ready for Acceptance (as defined
         in Schedule A), Winstar shall, at Winstar's expense, provide high
         capacity links between the Wam!Net node and the Winstar Terminal
         Facility that are engineered to Wam!Net's satisfaction to carry
         Wam!Net's customer traffic. Such high capacity links shall be
         maintained by Winstar until Wam!Net's node has been collocated with a
         Winstar switch center. Notwithstanding the foregoing, this obligation
         shall not become effective until the Parties have agreed upon a
         delivery schedule pursuant to Exhibit 3 of Schedule D.

                  (f) Winstar will be obligated to meet certain additional
         performance obligations related to the delivery and operations of the
         Intercity Backbone and the availability of the Capacity, all of which
         are contained in Exhibit 3 of Schedule C, which are incorporated herein
         by reference.

6. Purchase Price; Payment Terms

         6.1 Purchase of Capacity, Connectivity and Equipment. As of the
Effective Date, Wam!Net agrees to purchase the Capacity, connectivity,
collocation, and Equipment pursuant to the Transaction Documents and Winstar
agrees to provide the Capacity, connectivity, collocation, and Equipment
pursuant to the Transaction Documents for the Purchase Price. Except as
expressly provided in a Schedule, the Purchase Price will be the sole
consideration due to Winstar for the performance of any and all of its
obligations due under the Transaction Documents.

         6.2 Payment of Purchase Price. The Purchase Price shall be payable as
follows: (i) the Down Payment shall be paid upon execution of this Agreement;
and (ii) Two Hundred Forty Million Two Hundred Seventy-Nine Thousand Five
Hundred Ninety-Three Dollars and 00/100 ($240,279,593.00) shall be paid on the
terms and conditions set forth in Schedule 1, which shall be secured pursuant to
Schedule 2.

         6.3 Allocation. The Parties agree to allocate the Purchase Price (and
all other capitalizable costs) among the Network Facilities acquired and
Winstar's other obligations undertaken hereunder for all purposes (including
accounting and tax purposes) in accordance with the allocation table attached as
Schedule 3. Winstar and Wam!Net agree to report the allocation as provided in
the applicable sections of the Internal Revenue Code of 1986, as amended, and
regulations promulgated thereunder, in accordance with such allocation and agree
to prepare and file all income tax returns in a manner consistent with such
allocation.

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         6.4 Form of Payment. Wam!Net shall make payments under this Agreement
by wire transfer of immediately available funds to the United States bank
account or accounts designated by Winstar. At Winstar's discretion, payments to
be made pursuant to this Agreement may be made by check or draft of immediately
available funds delivered to the address designated in writing by Winstar or,
failing such designation, to the address for notice to Winstar pursuant to
Section 14.2.

         6.5 Taxes. The Parties' respective responsibilities for taxes arising
under or in connection with the Transaction Documents shall be as follows:

                  (a) Each Party shall be responsible for personal property
         taxes on property it owns or leases, for franchise and privilege taxes
         on its business, for taxes based on its net income or gross receipts,
         and for any third-party imposed fees.

                  (b) Each Party shall timely report and pay any and all sales,
         use, income, gross receipts, excise, transfer, ad valorem or other
         taxes, and any and all franchise fees or similar fees assessed against
         it due to the implementation of any facilities or equipment in
         connection with the Network Facilities.


                  (c) If a sales, use, excise, value-added, services,
         consumption, or other tax is assessed on the provision of the
         connectivity, maintenance or any other services, each Party shall
         timely report and pay any such tax assessed against it and the Parties
         shall work together to segregate the payments under this Agreement into
         two (2) payment streams:

                           (i)      Payments for taxable items; and

                           (ii)     Payments for other nontaxable items.

                  (d) The Parties agree to cooperate with each other to enable
         each to determine more accurately its own tax liability and to minimize
         such liability to the extent legally permissible. Each Party shall
         provide and make available to the other any resale certificates and
         other exemption certificates or information reasonably requested by
         either Party that is applicable to the subject matter of this
         Agreement.

                  (e) Each Party shall within thirty (30) business days notify
         the other of, and coordinate the response to and settlement of, any
         claim for taxes asserted by applicable taxing authorities for which the
         other Party is responsible hereunder. 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.

7. Confidentiality

         7.1 Confidential Information. Winstar and Wam!Net acknowledge that they
may be furnished with, receive, or otherwise have access to information of or

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concerning the other Party that such Party considers to be confidential,
proprietary, a trade secret or otherwise restricted. The terms and conditions of
the Transaction Documents shall be deemed Confidential Information.

         7.2 Obligations. The following obligations with respect to Confidential
Information shall survive the expiration or termination of this Agreement for a
period of seven (7) years or such longer period as required by regulation, law
or court order.

                  (a) Ongoing Obligation. Each Party's Confidential Information
         shall remain the property of that Party except as expressly provided
         otherwise by the other provisions of the Transaction Documents. Each
         Party shall each use at least the same degree of care, but in any event
         no less than a reasonable degree of care, to prevent unauthorized
         disclosure of Confidential Information as it employs to avoid
         unauthorized disclosure of its own information of a similar nature. The
         Parties may disclose such information to entities performing services
         required hereunder where: (i) use of such entity is authorized under
         the Transaction Documents, (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 the obligations
         described in this Section 7.2 Any disclosure to such entity shall be
         under the terms and conditions of this Section 7.2.

                  (b) Unauthorized Disclosure. Each Party shall take reasonable
         steps to ensure that its employees or agents comply with this Section.
         In the event of any 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, and (ii) take such actions as may be necessary and
         cooperate in all reasonable respects with the Disclosing Party to
         minimize the violation and any damage resulting therefrom.

                  (c) Permitted Disclosures.

                           (i) Either Party may disclose the terms and
                  conditions of the Transaction Documents to third parties that
                  (1) have expressed a bona fide interest in consummating a
                  significant financing, merger, acquisition, or strategic
                  commercial transaction between such third parties and such
                  Party, (2) have a reasonable ability (financial and otherwise)
                  to consummate such transaction, and (3) have executed a
                  nondisclosure agreement that includes within its scope the
                  terms and conditions of this Agreement and also includes a
                  procedure to limit the extent of copying and distribution of
                  this Agreement. Each Party shall endeavor to delay the
                  disclosure of the terms and conditions of the Transaction
                  Documents until the status of discussions concerning such
                  transaction warrants such disclosure.

                           (ii) If the Receiving Party becomes legally obligated
                  to disclose Confidential Information by any governmental
                  entity with jurisdiction over it, the Receiving Party will
                  give the Disclosing Party prompt written notice sufficient to
                  allow the Disclosing Party to seek a protective order or other
                  appropriate remedy. The Receiving Party will disclose only
                  such Confidential Information as is legally required

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                  and will use its reasonable best efforts to obtain
                  confidential treatment for any Confidential Information that
                  is so disclosed.

         7.3 No Implied Rights. Nothing contained in this Section shall be
construed as obligating a Party to disclose its Confidential Information to the
other Party, or as granting to or conferring on a Party, expressly or impliedly,
any rights or license to the Confidential Information of the other Party.

8. Termination.

         8.1 Termination.

                  (a) In the event that either Party commits an Event of
         Default, then the other Party may, by giving written notice (i)
         terminate this Agreement including any Schedule or Exhibit as set forth
         in Section 8.1(c) for cause as of a date specified in the notice of
         termination, and (ii) subject to the terms of this Article, pursue any
         legal remedies it may have under applicable law or principles of equity
         relating to such breach. Additional events which shall constitute
         Events of Default under this Agreement are detailed in Schedule 1. Any
         Event of Default may be waived in writing at the non-defaulting Party's
         option.

                  (b) Termination may also occur under the condition set forth
         in Section 11.6(d).

                  (c) If an Event of Default by Winstar exists under any one of
         Schedule A (Intercity Backbone), Schedule B (Equipment Sale), Schedule
         C (Installation and Maintenance), Schedule D (Terminal Facility
         Collocation Space) or Schedule E (Joint Marketing), Wam!Net, at its
         option, may elect to terminate the Transaction Documents in their
         entirety or only the affected Schedule. In the event that an Event of
         Default by Winstar exists under two or more of the schedules referenced
         in the previous sentence, Wam!Net may only elect to terminate all of
         the Transaction Documents in their entirety.

         8.2 Effect of Termination. Termination of this Agreement refers to the
termination of the Parties' respective commitments and obligations from and
after the date of termination, but does not relieve the Parties of their payment
and other obligations incurred prior to the date of termination and their
continuing obligations under Articles 7 and 12 or as may be specifically
provided in a Schedule.

9. Inducements. Each Party represents, warrants and covenants that it has not
offered or provided any inducements in violation of law or the other Party's
policies, of which it has been given notice, in connection with this Agreement.

10. Representations; Disclaimer

         10.1 Representations. Each Party represents and warrants to the other
that:

                                       12
<PAGE>

                  (a) It has the requisite corporate power and authority to
         enter into the Transaction Documents and to carry out the transactions
         contemplated by the Transaction Documents; and

                  (b) The execution, delivery and performance of the Transaction
         Documents and the consummation of the transactions contemplated by the
         Transaction Documents have been duly authorized by the requisite
         corporate action on the part of such Party. (c) Each Party represents
         that the Transaction Documents have been duly executed and delivered,
         and create lawful, valid and legally binding obligations, in accordance
         with their respective terms. The execution and delivery of the
         Transaction Documents and the consummation of the transactions
         contemplated hereby are not prohibited by, do not violate or conflict
         with any provision of, and do not constitute a default under or a
         breach of: (a) any contract, agreement or other instrument to which it
         is a party or by which any of the assets that are the subject hereof
         are bound; or (b) to the Party's knowledge, any order, writ,
         injunction, decree or judgment of any court or governmental agency.

         10.2 Winstar represents that the Network Facilites will function in
accordance with the terms of the Transaction Documents for the Term.

         10.3 Winstar covenants and agrees that it has or shall obtain any and
all rights, licenses, permits, authorizations, consents and approvals
(including, without limitation, any necessary local, state, federal or tribal
authorizations and environmental permits) as are reasonably necessary in order
to permit Winstar to perform all of its obligations under the Transaction
Documents, and to permit Wam!Net to use the Capacity and the connectivity as
provided and permitted hereunder.

         10.4 Manufacturers' Equipment Warranty. Winstar will pass through to
Wam!Net all warranties from the manufacturers of the Equipment to the extent
Winstar is able pursuant to any agreements between Winstar and such
manufacturers. Notwithstanding the foregoing, the existence of such
manufacturers' warranties does not diminish or limit Winstar's obligations under
Schedule C.

         10.5 Disclaimer. EXCEPT AS SPECIFICALLY SET FORTH IN THE TRANSACTION
DOCUMENTS, THE PARTIES MAKE NO WARRANTY TO EACH OTHER OR ANY OTHER ENTITY,
WHETHER EXPRESS, IMPLIED OR STATUTORY, AS TO THE MERCHANTABILITY OR FITNESS FOR
ANY PARTICULAR PURPOSE OF THE EQUIPMENT, NETWORK FACILITIES, ANY CAPACITY, IRUs,
CONNECTIVITY, MAINTENANCE, MANAGEMENT, ANCILLARY SERVICES OR ANY OTHER
EQUIPMENT, FACILITIES OR SERVICES PROVIDED OR USED HEREUNDER OR DESCRIBED
HEREIN, OR AS TO ANY OTHER MATTER, ALL OF WHICH WARRANTIES ARE HEREBY EXPRESSLY
EXCLUDED AND DISCLAIMED.

                  IN NO EVENT, WHETHER IN CONTRACT OR IN TORT (INCLUDING BREACH
OF WARRANTY, NEGLIGENCE AND STRICT LIABILITY IN TORT), SHALL

                                       13
<PAGE>

A PARTY BE LIABLE FOR INDIRECT OR CONSEQUENTIAL, EXEMPLARY, PUNITIVE OR SPECIAL
DAMAGES EVEN IF SUCH PARTY HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH DAMAGES
IN ADVANCE.

11. Liability

         11.1 General Intent. Subject to the specific provisions of this Article
11, it is the intent of the Parties that each Party shall be liable to the other
Party only for any direct damages incurred by the non-breaching Party as a
result of the breaching Party's failure to perform its obligations in the manner
required by the Transaction Documents.

         11.2 Liability Restrictions.

                  (a) Winstar's liability to Wam!Net whether in contract or in
         tort (including breach of warranty, negligence and strict liability in
         tort) shall be limited to the amounts actually paid (including both
         principal and interest) to Winstar by Wam!Net at the time the event
         resulting in liablity occurs.

                  (b) The limitation set forth in Subsection (a), above, shall
         not apply with respect to: (i) third-party claims subject to
         indemnification pursuant to the Agreement; or (ii) fees due and owing
         under this Agreement at the time of the claim.

                  (c) For the purposes of this Section 11.2, all amounts payable
         or paid to third parties in connection with claims that are eligible
         for indemnification pursuant to this Agreement shall be deemed direct
         damages.

         11.3 Insurance Requirements.

                  (a) During the Term each Party shall obtain and maintain, at
         its expense, an appropriate insurance policy with terms and coverage
         thresholds equal to the amounts below and provide the other Party with
         a certificate of such coverage upon request. Winstar will assist
         Wam!Net to the extent reasonably requested in the coordination of all
         insurance claims against Wam!Net's own insurer for any event of loss.
         Wam!Net shall be responsible for all of Winstar's third-party costs
         reasonably incurred as a result of such coordination other than
         Winstar's internal costs. During the Term, each Party shall have and
         maintain in force the following insurance coverages:

                           (i) Worker's Compensation and Employer's Liability.
                  Worker's Compensation Insurance in amounts required by
                  applicable law and Employers Liability Insurance with limits
                  not less than $1,000,000 each accident.

                           (ii) Commercial General Liability. Each Party shall
                  carry broadform general liability insurance coverage for
                  property damage, bodily injury, personal injury, and
                  contractual liability with coverage of at least $10,000,000
                  per occurrence and in the aggregate. Total limits can be
                  attained by the inclusion of an Umbrella/Excess Liability
                  policy.

                                       14
<PAGE>

                  (b) Each Party shall cause its insurers to issue certificates
         of insurance evidencing that the coverages required under this
         Agreement are maintained in force. The minimum limits of coverage
         specified herein are not intended, and shall not be construed, to limit
         any liability or indemnity of either Party under this Agreement.

                  (c) Nothing in this Agreement shall be construed to prevent
         either Party satisfying its insurance obligations pursuant to this
         Agreement under a blanket policy or policies of insurance that meet or
         exceed the requirements of this Article.

         11.4 Risk of Loss.

                  (a) For the Network Facilities and any support services
         provided under the Transaction Documents, each Party shall take all
         reasonable precautions against, and shall assume liability for, subject
         to the terms of the Transaction Documents, any damage caused by it to
         the property of the other Party. Winstar shall bear the risk of loss
         with regard to the equipment and facilities owned by Winstar that it
         uses to meet its obligations to Wam!Net under the Transaction
         Documents; provided, however, that Wam!Net shall be responsible for all
         damage and loss to such equipment and facilities caused by Wam!Net's
         gross negligence or willful misconduct.

                  (b) Except as otherwise contemplated herein, for the duration
         of the Security Interest granted pursuant to Schedule 2, Wam!Net shall
         not cause or permit any part of the Network Facilities to become
         subject to any lien, security interests, or encumbrances whether by
         operation of law or otherwise.

         11.5 Performance Obligations Limitation.

                  In the event that Winstar commits a breach of a performance
         obligation imposed in any of the Exhibits to the Schedules, then
         Winstar shall provide Wam!Net with a Performance Enhancement credit
         towards future purchases of Intercity Backbone IRUs, Equipment,
         connectivity, any support services obtained from Winstar pursuant to a
         Transaction Document, or any third party carrier's backhaul services
         for the Wam!Net network, in the amount(s) set forth in the applicable
         Exhibit.

         11.6 Force Majeure.

                  (a) Subject to Section 11.6(d), neither Party shall be liable
         for any default or delay in the performance of its obligations under
         the Transaction Documents 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, war, riots, civil disorders,
         rebellions or revolutions, provided that such default or delay could
         not have been prevented by reasonable precautions and cannot be
         reasonably circumvented by the non-performing Party through the use of
         alternate sources, workaround plans or other means, including to the
         extent contemplated by applicable disaster recovery processes or
         procedures.

                                       15
<PAGE>

                  (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 commercially reasonable efforts to recommence performance or
         observance whenever and to whatever extend possible without delay.

                  (c) The term of a Party's performance of any obligation(s)
         excused by a force majeure event shall be extended by any period(s) of
         force majeure.

                  (d) If any period of force majeure affecting Winstar's
         obligations under any Transaction Documents extends for more than
         thirty (30) days, and (i) if the force majeure event affects all or
         substantially all of the Network Facilities (a "Major Force Majeure
         Event"), then either Party may, at its option, terminate this Agreement
         upon twenty (20) days prior written notice to the other, and in that
         event, Winstar's failure to perform its obligation shall be considered
         a non-excused breach; or (ii) for any force majeure event that is not a
         Major Force Majeure Event (a "Minor Force Majeure Event"), then for a
         period of one hundred eighty days (180) thereafter, Winstar will
         provide Wam!Net with a Performance Enhancement credit towards future
         purchases of Intercity Backbone IRUs, Equipment, connectivity, any
         support services obtained from Winstar pursuant to a Transaction
         Document, or any third party carrier's backhaul services for the
         Wam!Net network, in the amount set forth in Exhibit 3 of Schedule C. If
         after such one hundred eighty (180) day period, Winstar is unable to
         perform its obligations with respect to the portion of the Network
         Facilities affected by such Minor Force Majeure Event, Wam!Net may
         terminate the portion of the Transaction Documents applicable to such
         obligation, and in such event, Winstar's inability to perform such
         obligation shall be considered a non-excused breach.

12. Indemnification

         12.1 Indemnities by Winstar. Winstar agrees to indemnify, defend and
hold harmless Wam!Net and its Affiliates and their respective officers,
directors, employees, agents, successors, and assigns, from any and all Losses
and threatened Losses arising from, in connection with, or based on allegations
of, any of the following:

                  (a) Winstar's failure to observe or perform any duties or
         obligations to third parties (e.g., duties or obligations to
         subcontractors);

                  (b) Any claims of infringement of any patent, trade secret,
         copyright or other proprietary rights, alleged to have occurred based
         upon the provision of the Network Facilities by Winstar, except to the
         extent that such claims arise from (i) modification of the Network
         Facilities or any component thereof by Wam!Net that is not recommended
         or otherwise approved by Winstar, (ii) maintenance of the Network
         Facilities by Wam!Net other than in accordance with the provisions set
         forth in the Transaction Documents that is not recommended or otherwise
         approved by Winstar, or (iii) use of the Network Facilities by Wam!Net
         in combination with deliverables furnished by third parties that is not
         recommended or otherwise approved by Winstar;

                                       16
<PAGE>

                  (c) The death or bodily injury of any agent, employee,
         customer, business invitee or any other person caused by the tortious
         conduct of Winstar;

                  (d) The damage, loss or destruction of any real or tangible
         personal property caused by the tortious conduct of Winstar; or

                  (e) Any claim, demand, charge, action, cause of action, or
         other proceeding asserted against Wam!Net but resulting from an act or
         omission of Winstar in its capacity as an employer of a person.

         12.2 Indemnities by Wam!Net. Wam!Net agrees to indemnify, defend and
hold harmless Winstar and its Affiliates and their respective officers,
directors, employees, agents, successors, and assigns, from any and all Losses
and threatened Losses arising from, in connection with, or based on allegations
of, any of the following:

                  (a) Wam!Net's failure to observe or perform any duties or
         obligations to third parties (e.g., duties or obligations to
         subcontractors);

                  (b) Any claims of infringement of any patent, trade secret,
         copyright or other proprietary rights, alleged to have occurred based
         upon misuse of the Network Facilities by Wam!Net, including (i)
         modification of the Network Facilities or any component thereof by
         Wam!Net that is not recommended or otherwise approved by Winstar, (ii)
         maintenance of the Network Facilities other than by Winstar or
         Winstar's designees in accordance with the provisions set forth in the
         Transaction Documents that is not recommended or otherwise approved by
         Winstar, or (iii) use of the Network Facilities by Wam!Net in
         combination with deliverables furnished by third parties that is not
         contemplated by the Transaction Documents, recommended or otherwise
         approved by Winstar;

                  (c) The death or bodily injury of any agent, employee,
         customer, business invitee or any other person caused by the tortious
         conduct of Wam!Net;

                  (d) The damage, loss or destruction of any real or tangible
         personal property caused by the tortious conduct of Wam!Net; or

                  (e) Any claim, demand, charge, action, cause of action, or
         other proceeding asserted against Winstar but resulting from an act or
         omission of Wam!Net in its capacity as an employer of a person.

         12.3 Infringement. If any item used by Winstar to provide the Network
Facilities becomes, or in Winstar's reasonable opinion is likely to become, the
subject of an infringement or misappropriation claim or proceeding, in addition
to indemnifying Wam!Net as provided in this Article 12 by Winstar and to the
other rights Wam!Net may have under the Transaction Documents, Winstar shall,
promptly at Winstar's expense:

                                       17
<PAGE>

                  (a) secure the right to continue using the item, or

                  (b) if the action described in Subsection (a) cannot be
         accomplished by Winstar, replace or modify the item to make it
         non-infringing, provided that any such replacement or modification will
         not degrade the fit, form or function of the affected Network
         Facilities.

         12.4 Indemnification Procedures. With respect to third-party claims,
the following procedures shall apply:

                  (a) Promptly after receipt of notice of the commencement or
         threatened commencement of any civil, criminal, administrative, or
         investigative action or proceeding involving a claim in respect of
         which Indemnitee will seek indemnification pursuant to this Article,
         Indemnitee will notify Indemnitor of such claim in writing. No failure
         to so notify Indemnitor will relieve Indemnitor of its obligations
         under this Agreement except to the extent that it can demonstrate
         damages attributable to such failure. Within fifteen (15) Days
         following receipt of written notice from Indemnitee relating to any
         claim, but no later than ten (10) Days before the date on which any
         response to a complaint or summons is due, Indemnitor will notify
         Indemnitee in writing if Indemnitor elects to assume control of the
         defense and settlement of that claim (a "Notice of Election").

                  (b) If Indemnitor delivers a Notice of Election relating to
         any claim within the required notice period, Indemnitor shall be
         entitled to have sole control over the defense and settlement of such
         claim; provided that (i) Indemnitee shall be entitled to participate in
         the defense of such claim and to employ counsel at its own expense to
         assist in the handling of such claim, and (ii) Indemnitor shall obtain
         the prior written approval of Indemnitee before entering into any
         settlement of such claim or ceasing to defend against such claim. After
         Indemnitor has delivered a Notice of Election relating to any claim in
         accordance with the preceding paragraph, Indemnitor shall not be liable
         to Indemnitee for any legal expenses incurred by Indemnitee in
         connection with the defense of that claim. In addition, Indemnitor
         shall not be required to indemnify Indemnitee for any amount paid or
         payable by the Indemnitee in the settlement of any claim for which the
         Indemnitor has delivered a timely Notice of Election if such amount was
         agreed to without the written consent of the Indemnitor.

                  (c) If Indemnitor does not deliver a Notice of Election
         relating to any claim within the required notice period, Indemnitee
         shall have the right to defend the claim in such manner as it may in
         its reasonable judgement deem appropriate, at the cost and expense of
         Indemnitor. Indemnitor shall promptly reimburse Indemnitee for all such
         costs and expenses.

13. Dispute Resolution Any dispute between the Parties arising out of or
relating to the Transaction Documents, shall be resolved as provided in this
Section.

         13.1 Informal Dispute Resolution.

                                       18
<PAGE>

                  (a) Prior to the initiation of formal dispute resolution
         procedures, the Parties shall first attempt to resolve their dispute
         informally pursuant to this Section. Upon the written request of a
         Party, each Party shall appoint a representative from its senior
         management who does not devote substantially all of his or her time to
         performance under the Transaction Documents, whose task it will be to
         meet for the purpose of endeavoring to resolve such dispute. If, after
         thirty (30) days from the written request the representatives from
         senior management have not resolved such dispute, each Party shall
         appoint a representative from its executive management whose task it
         will be to meet for the purpose of endeavoring to resolve such dispute.
         If, after sixty (60) days from the appointment of such representatives
         from executive management, the representatives have not resolved such
         dispute, then the provisions of Section 13.2 shall apply.

                           (i) The designated representatives shall meet as
                  often as the Parties reasonably deem necessary in order to
                  gather and furnish to the other all information with respect
                  to the matter in issue which the Parties believe to be
                  appropriate and germane in connection with its resolution. The
                  representatives shall discuss the problem and attempt to
                  resolve the dispute without the necessity of any formal
                  proceeding.

                           (ii) During the course of discussion, all reasonable
                  requests made by one Party to another for non-privileged
                  information, reasonably related to this Agreement, shall be
                  honored in order that each of the Parties may be fully advised
                  of the other's position.

                           (iii) The specific format for the discussions shall
                  be left to the discretion of the designated representatives.

                  (b) The Parties agree that disputes, controversies or claims
         between them shall not be subject to the provisions of this Section
         where:

                           (i) A Party makes a good faith determination that a
                  breach of the terms of the Transaction Documents by the other
                  Party is such that a temporary restraining order or other
                  injunctive relief is the only appropriate and adequate remedy;
                  or

                           (ii) Institution of formal proceedings earlier than
                  as set forth in this Section 13.1 for the resolution of a
                  dispute may be commenced after the earlier of (x) a good faith
                  determination that such proceedings are necessary to avoid the
                  expiration of any applicable limitations period or (y) to
                  preserve a superior position with respect to other creditors.

                  (c) If a Party files a pleading with a court seeking immediate
         injunctive relief and this pleading is challenged by the other Party
         and the injunctive relief sought is not awarded in substantial part,
         the Party filing the pleading seeking immediate injunctive relief shall
         pay all of the costs and attorneys' fees of the Party successfully
         challenging the pleading.

                                       19
<PAGE>

         13.2 Arbitration.

         Except as providided in Section 13.1(b) any dispute, controversy or
claim arising out of or relating to the Transaction Documents or the breach,
termination or validity thereof, shall be finally settled in accordance with the
commercial arbitration rules of the American Arbitration Association (the "AAA")
then obtaining, by a panel of three arbitrators. Each party shall have the right
to appoint one arbitrator from the list of arbitrators supplied to the parties
by the AAA, and the two arbitrators so appointed shall appoint the third.

         The place of arbitration shall be the City of New York, New York,
U.S.A. The language of the arbitration shall be in English. The arbitrators
shall determine the matters in dispute in accordance with the internal law of
the State of New York, without reference to the Convention on Contracts for the
International Sale of Goods. Except as precluded by the United Nations
Convention on the Recognition and Enforcements of Foreign Arbitral Awards, the
internal procedural and substantive laws of New York and the United States
Federal Arbitration Act shall govern all questions of arbitral procedure,
arbitral review, scope of arbitral authority, and arbitral enforcement.

         The parties agree that the award of the arbitrators shall be the sole
and exclusive remedy between them regarding any claims, counterclaims, issues or
accountings presented or pled to the arbitrators, that the award shall be made
and shall be promptly payable in U.S. dollars, free of any tax, deduction or
offset, and that any costs, fees or taxes instant to enforcing the award shall,
to the maximum extent permitted by law, be charged against the party resisting
such enforcement.

         The award shall include interest from the date of damages incurred for
breach or other violation of the Transaction Documents, and from the date of the
award until paid in full, at a rate to be fixed by the arbitrators.

         No claim may be submitted by a party to arbitration in accordance with
this Article 13 unless notified to the other party within one (1) year of the
date on which the submitting party first knew or should have known of the
existence of the facts indicating the existence of such dispute.

         13.3 Continued Performance. Each Party agrees to continue performing
its obligations under the Transaction Documents 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).

         13.4 Governing Law. The Transaction Documents and performance under
them shall be governed by and construed in accordance with the laws of the State
of New York without regard to its choice of law principles and the Convention or
Contracts for the International Sale of Goods.

14. General

                                       20
<PAGE>

         14.1 Binding Nature and Assignment.

                  (a) The Transaction Documents 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.

                  (b) Except as expressly provided in a Transaction Document,
         neither Party may, or shall have the power to, assign the Transaction
         Documents or delegate such Party's obligations hereunder without the
         prior written consent of the other, except that either Party may assign
         its rights and obligations under the Transaction Documents without the
         approval of the other Party to

                           (i) an entity which acquires all or substantially all
                  of the assets of the assigning party,

                           (ii) to any Affiliate, in which event the assignor
                  shall remain liable as a guarantor of the assignee/Affiliate's
                  performance of such Party's obligations hereunder, or

                           (iii) to a successor in a merger or acquisition.

         14.2 Notices. Any notices, requests, demands, and determinations under
this Agreement (other than routine operational communications), 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:

If to Wam!Net:                         If to Winstar:

Wam!Net Inc.                           Winstar Wireless, Inc.
655 Lone Oak Drive                     7799 Leesburg Pike
Eagan, MN  55121                       Suite 700 South
Attn:  Gary Hokkanen, President        Tysons Corner, VA  22043
Facsimile:  (651) 994-9591             Attn: Robert K. McGuire, President
                                             and Chief Operating Officer
                                             Winstar Large Accounts
                                       Facsimile:  (703) 226-7649

With a copy to:                        With a copy to:

Wam!Net Inc.                           Winstar Wireless, Inc.
655 Lone Oak Drive                     7799 Leesburg Pike

                                       21
<PAGE>

Eagan, MN  55121                       Suite 700 South
Attn:  Lisa Gray                       Tysons Corner, VA  22043
General Counsel                        Attn:  Colleen R. Jones
Facsimile:  (651) 256-5176                    Chief Counsel
                                              Winstar Large Accounts
                                       Facsimile:  (703) 226-7649


         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.

         14.3 Counterparts. The Transaction Documents may be executed in several
counterparts, all of which taken together shall constitute one single agreement
between the Parties hereto.

         14.4 Relationship of Parties. Winstar, in furnishing the Network
Facilities and other services hereunder, is acting as an independent contractor,
and Winstar personnel (including, without limitation, and any subcontractors)
shall not be considered or represented as employees or agents of Wam!Net.
Winstar is not otherwise an agent of Wam!Net and has no authority to represent
Wam!Net as to any matters, except as expressly authorized in the Transaction
Document. Winstar is solely responsible for: (a) performing its responsibilities
under the Transaction Documents, (b) management and control of its personnel;
(c) the payment of all compensation owed to its personnel, including payment of
employment-related taxes, benefits, and worker's compensation insurance; (d) the
filing of all required employment returns and reports; and (e) the withholding
and payment of all applicable federal, state, and local taxes and other wage or
employment assessments, including but not limited to income tax, social security
tax, and unemployment insurance premiums for its personnel.

         14.5 Severability.

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

                  (b) If such modification would substantially deprive either
         party of the economic benefit of the Transaction Documents as
         originally executed, then that Party may terminate the Transaction
         Documents. Any disputes over whether a modification under this Section
         should allow a termination of the Transaction Documents shall be
         resolved in accordance with Section 13.

                                       22
<PAGE>

                  (c) If the FCC or any state body of competent jurisdiction
         determines that any provision of the Transaction Documents violates any
         applicable rules, policies, or regulations, both Parties shall make
         reasonable efforts to immediately bring the Transaction Documents into
         compliance and shall endeavor in those efforts to preserve for both
         Parties the economic benefits as reflected in the Transaction Documents
         to the maximum extent possible. If it is impossible to preserve the
         economic benefits, then Section 14.5(b) will apply.

         14.6 Consents and Approval. Except where expressly provided as being in
the sole discretion of a Party, where agreement, approval, acceptance, consent,
or similar action by either Party is required under this Agreement, such action
shall not be unreasonably delayed or withheld. An approval or consent given by a
Party under this Agreement shall not relieve the other Party from responsibility
for complying with the requirements of the Transaction Documents, nor shall it
be construed as a waiver of any rights under the Transasction Documents, except
as and to the extent otherwise expressly provided in such approval or consent.

         14.7 Waiver of Default. No 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
the Transaction Documents shall not be construed to be a waiver thereof. A
waiver by either of the Parties 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.

         14.8 Cumulative Remedies. Except as otherwise expressly provided, all
remedies provided for in the Transaction Documents 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.

         14.9 Survival. Any provision of the Transaction Documents which
contemplates performance or observance subsequent to any termination or
expiration of the Transaction Documents (in whole or in part) shall survive any
termination or expiration of the Transaction Documents (in whole or in part, as
applicable) and continue in full force and effect.

         14.10 Public Disclosures. All media releases, public announcements, and
public disclosures relating to this Agreement or the subject matter of this
Agreement, including promotional or marketing material, but not including
announcements intended solely for internal distribution or disclosures to the
extent required to meet legal or regulatory requirements beyond the reasonable
control of the disclosing Party, shall be coordinated with and shall be subject
to approval by each Party prior to release.

         14.11 Third Party Beneficiaries. Except as otherwise provided in the
Transaction Documents, the Transaction Documents shall not be deemed to create
any

                                       23
<PAGE>

rights in third parties, including suppliers and customers of a Party, or to
create any obligations of a Party to any such third parties.

         14.12 Amendment. The Transaction Documents shall not be modified,
amended or in any way altered except by an instrument in writing signed by both
Parties.

         14.13 Interpretation.

                  (a) Terms other than those defined in the Transaction
         Documents shall be given their plain English meaning, and those terms,
         acronyms and phrases known in the telecommunications and information
         technology services industries shall be interpreted in accordance with
         their generally known meanings. Unless the context otherwise requires,
         words importing the singular include the plural and vice-versa.

                  (b) References to "Article," "Section," "Subsection" and
         "Schedule" mean references to an article, section, subsection or
         schedule of the Transaction Documents, as appropriate, unless otherwise
         specifically stated.

                  (c) The article and section headings in the Transaction
         Documents are intended to be for reference purposes only and shall in
         no way be construed to modify or restrict any of the terms or
         provisions of the Transaction Documents.

                  (d) The words "include," "includes," and "including," when
         following a general statement or term, are not to be construed as
         limiting the general statement or term to any specific item or matter
         set forth or to similar items or matters, but rather as permitting the
         general statement or term to refer also to all other items or matters
         that could reasonably fall within its broadest scope.

                  (e) All dollar amounts referred to in the Transaction
         Documents are in United States dollars.

         14.14 Incorporation by Reference and Order of Precedence.

                  (a) Any conflict among or between the documents making up the
         Transaction Documents will be resolved in accordance with the following
         order of precedence (in descending order of precedence):

                           (i)      The Exhibits;
                           (ii)     The Schedules, and
                           (iii)    The Agreement.

                  (b) In the event of conflict between the documents making up
         the Transaction Documents and the terms and conditions of any purchase
         order issued by either Party, the terms of the Transaction Documents
         shall supersede any such purchase order.

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<PAGE>

         14.15 Entire Agreement. The Transaction Documents, constitute the
entire agreement between the Parties with respect to the subject matter in this
Agreement, and supersede all prior agreements, whether written or oral, with
respect to the subject matter contained in this Agreement.

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<PAGE>

IN WITNESS WHEREOF, this Agreement has been executed and delivered by the
undersigned officers, thereunto, duly authorized, as of the date first written
above.

WAM!NET INC.                        WINSTAR WIRELESS, INC.

By: /s/ Edward J. Driscoll          By: /s/ Ken Patterson
   -------------------------           ----------------------------
Name:                               Name:
     -----------------------             --------------------------
Title:                              Title:
      ----------------------              -------------------------
Date:                               Date:
     -----------------------             --------------------------

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