<PAGE>

                                                                   Exhibit 10.39

         INTERCONNECTION AGREEMENT UNDER SECTIONS 251 AND 252 OF THE
                        TELECOMMUNICATIONS ACT OF 1996

                          Dated as of March 13, 2000

                                by and between


                       BELL ATLANTIC - PENNSYLVANIA, INC

                                      and

                           BROADVIEW NETWORKS, INC.





<PAGE>



         INTERCONNECTION AGREEMENT UNDER SECTIONS 251 AND 252 OF THE

                        TELECOMMUNICATIONS ACT OF 1996


    This Interconnection Agreement (this "Agreement"), under Sections 251 and
252 of the Telecommunications Act of 1996 (the "Act"), is effective as of the
13th day of March 2000 (the "Effective Date"), by and between Bell Atlantic
Pennsylvania, Inc. ("BA"), a Pennsylvania corporation with offices at 1717
Arch Street, Philadelphia, Pennsylvania 19103, and Broadview Networks, Inc.
("Broadview") a Delaware corporation with offices at 45-18 Court Square, Suite
300 Long Island City, New York 11101 (each individually, a "Party" and,
collectively, the "Parties").

    WHEREAS, Broadview has requested, pursuant to Section 252(i) of the Act,
that BA make available to Broadview Interconnection, services and unbundled
Network Elements upon the same terms and conditions as provided in the
Interconnection Agreement (and any amendments thereto that have been approved
under applicable law) between MCImetro Access Transmission Services, Inc. and
BA, dated as of September 3, 1997 for the Commonwealth of Pennsylvania, approved
by the Commission under Section 252 of the Act, copies of which agreement and
any subsequent amendments thereto that have been approved under applicable law
being attached hereto as Appendix 1 (the "Separate Agreement"); and

    WHEREAS, BA has undertaken to make such terms and conditions available to
Broadview hereby only because of, and to the extent required by, Section
252(i)of the Act.

    NOW, THEREFORE, in consideration of the mutual provisions contained herein,
and for other good and valuable consideration, the receipt and sufficiency of
which are hereby acknowledged, Broadview and BA hereby agree as follows:

    1.0   Incorporation of Separate Agreement and Appendix 2 by Reference

    1.1   Except as expressly stated herein, the terms and conditions of the
Separate Agreement, as it is in effect on the date hereof after giving effect to
operation of law, and of Appendix 2 attached hereto, are incorporated by
reference in their entirety herein and form an integral part of this Agreement.

    1.2   References in the Separate Agreement to MCImetro Access Transmission
Services, Inc., or to MCIm or to MCI shall for purposes of this Agreement be
deemed to refer to Broadview.

    1.3   References in the Separate Agreement to the "Effective Date", the date
of effectiveness thereof and like provisions shall for purposes of this
Agreement be deemed to refer to the date first written above. Unless terminated
earlier in accordance with the terms of the Separate Agreement, this Agreement
shall continue in effect until the later of the date (a)of the


                                       2
<PAGE>

expiration of the initial term of the Separate Agreement (which, for the
avoidance of any doubt, is August 31, 2000) or (b) the Separate Agreement is
otherwise terminated or expires.

     1.4  All references in the Separate Agreement to "800/888" shall be deleted
in their entirety and replaced with the following: "800/888/877".

     1.5  All usage data to be provided pursuant to Sections 3.1.3.8 and 3.1.3.9
of Attachment VIII of the Separate Agreement shall be sent to the following
address on behalf of Broadview:

          Tim Bell
          Broadview Networks, Inc.
          45-18 Court Square
          Suite 300
          Long Island City, New York 11101


     1.6  All certificates or other proof of insurance to be sent to BA under
Section 15 of Attachment VI of the Separate Agreement shall be sent to the
following address:

          Director - Interconnection Services
          Bell Atlantic - Telecom Industry Services
          Room 1423
          1095 Avenue of the Americas
          New York, New York 10036


     1.7  All notices, affidavits, exemption-certificates or other
communications to Broadview under Section 27.7 of Part A of the Separate
Agreement shall be sent to the following address:


          Mr. Larry Edelson-Kane
          Broadview Networks, Inc.
          45-18 Court Square - Suite 300
          Long Island City, NY 11101


     1.8  All notices, affidavits, exemption-certificates or other
communications to BA under Section 27.7 of Part A of the Separate Agreement
shall be sent to the following address:

          Tax Administration
          Bell Atlantic Corporation
          1095 Avenue of the Americas

                                       3
<PAGE>

          Room 3109
          New York, New York 10036
          Telephone: (212) 395-1280
          Facsimile: (212) 597-2915

    1.9 Notices to Broadview under Section 14.1 of Part A of the Separate
Agreement shall be sent to the following address:

          Mr. Terrence J. Anderson
          Broadview Networks, Inc.
          45-18 Court Square - Suite 300
          Long Island City, NY 11101
          Telephone: (718) 707-8890
          Facsimile: (718) 706-9416

     1.10 Notices to BA under Section 14.1 of Part A of the Separate Agreement
shall be sent to the following address:

          Director - Interconnection Services
          Bell Atlantic Wholesale Markets
          1095 Avenue of the Americas
          Room 1423
          New York, NY 10036
          Facsimile: 212/704-4381

          with a copy to:

          Bell Atlantic Network Services, Inc.
          Attn: Jack H. White, Jr.,
              Associate General Counsel
          1320 N. Court House Road, 8th Floor
          Arlington, Virginia 22201
          Telephone: (703) 974-1368
          Facsimile: (703) 974-0744

          with a copy to:

          Bell Atlantic-Pennsylvania, Inc.
          Attn: General Counsel
          37th Floor
          1717 Arch Street
          Philadelphia, PA 19103

                                       4
<PAGE>

1.ll  The rates, charges and other terms set forth in Appendix 2 hereto shall
replace and supersede in their entirety the rates, charges and other terms set
forth in Table 1 of Attachment 1 to the Separate Agreement.

    2.0   Clarifications

    2.1   Part B, definition of "Local Traffic" set forth at Section 1.71 of
    Part B of the Separate Agreement, is hereby deleted in its entirety and
    replaced as follows:
               "'Local Traffic' means traffic that is originated by an end user
         subscriber of one Party on that Party's network and terminates to an
         end user subscriber of the other Party on that other Party's network
         within a given local calling area, or expanded area service
         ("EAS")area, as defined in Bell Atlantic's Tariffs, or, if the
         Commission has defined local calling areas applicable to all Local
         Exchange Carriers, then as so defined by the Commission. In addition,
         Local Traffic does not include any traffic that is transmitted to or
         returned from the Internet at any point during the duration of the
         transmission ('Internet Traffic')."

               (b) A new sentence (on reciprocal compensation arrangements) is
         hereby added at the end of Section 2.4.3 of Attachment IV of the
         Separate Agreement, as follows:

                    "In addition, the reciprocal compensation arrangements set
               forth in this Agreement are not applicable to exchange access,
               including origination or termination of Internet Traffic".

    2.2   The Parties agree that if any judicial or regulatory authority of
competent jurisdiction determines (or has determined) that BA is not required to
furnish any service or item or provide any benefit to Telecommunications
Carriers otherwise required to be furnished or provided to Broadview hereunder,
then BA may, at its sole option, avail itself of any such determination by
providing written notice thereof to Broadview.

    2.3   Notwithstanding anything to the contrary contained in this Agreement,
the Parties agree that BA shall only be required to provide Combinations and any
services related to its provision of Combinations to the extent (a)required by
Applicable Law or (b) mutually agreed to by the Parties in writing after the
date hereof.

    2.4   For the avoidance of doubt, the Parties acknowledge and agree that
the term "Dedicated Transport", as described in Section 10 of Attachment III of
the Separate Agreement, includes subscriber premises only if such premises
contain Central Office switching equipment used for interoffice transmission to
and from the other end of the Dedicated Transport path.

    2.5   The entry into, filing and performance by BA of this Agreement does
not in any way constitute a waiver by BA of any of the rights and remedies it
may have to seek review of any of the provisions of the Separate Agreement, or
to petition the Commission, other administrative body or court for
reconsideration or reversal of any determination made by any of

                                       5
<PAGE>

them, or to seek review in any way of any portion of this Agreement in
connection with Broadview's election under Section 252(i) of the Act.

    2.6 Notwithstanding any other provisions of this Agreement, BA shall have no
obligation to perform under this Agreement until such time as Broadview has
obtained a Certificate of Public Convenience and Necessity ("CPCN") or such
other Commission authorization as may be required by law as a condition for
conducting business in the Commonwealth of Pennsylvania as a local exchange
carrier.

                                       6
<PAGE>

    IN WITNESS WHEREOF, the Parties hereto have caused this Agreement to be
executed as of the date first set forth above.


BROADVIEW NETWORKS, INC.                BELLATLANTIC - PENNSYLVANIA, INC.


By:  /s/ Eric G. Roden                  By: /s/ Michael A. Daly
   --------------------------              -----------------------------


Printed: Eric G. Roden                  Printed: For Jeffrey A. Masoner
        ---------------------                   ------------------------

Title: Chief Operating Officer          Title: Vice-President - Interconnection
       -----------------------                 --------------------------------
                                               Services Policy & Planning
                                               --------------------------
<PAGE>

                                  APPENDIX 1
<PAGE>

                               TABLE OF CONTENTS





   A. GENERAL TERMS AND CONDITIONS                              A-2

     Section 1 - Scope of This Agreement                        A-2
     1.4 Construction                                           A-3

     Section 2 - Regulatory Approvals                           A-4

     Section 3 - Term of Agreement                              A-5

     Section 4 - Charges and Payment                            A-6

     Section 5 - Assignment                                     A-6

     Section 6 - Compliance with Laws                           A-6

     Section 7 - Governing Law                                  A-7

     Section 8 - Relationship of Parties                        A-7

     Section 9 - No Third Party Beneficiaries                   A-8

     Section 10 - Intellectual Property Rights                  A-8

     Section 11 - Indemnification                               A-9

     Section 12 - Limitation of Liability                       A-10

     Section 13 - Warranties                                    A-11

     Section 14 - Notices                                       A-12

     Section 15 - Technical References                          A-13

     Section 16 - Remedies                                      A-14

     Section 17 - Waivers                                       A-14

     Section 18 - Survival                                      A-15

     Section 19 - Force Majeure                                 A-15



      MCIm-BELL ATLANTIC INTERCONNECTION AGREEMENT-PENNSYLVANIA     PART A-i
<PAGE>

July 8, 1997                                                           PART A


     Section 20 - Publicity                                             A-20

     Section 21 - Default and Termination                               A-16
     21.3 Billing Disputes                                              A-16

     Section 22 - Confidentiality                                       A-18

     Section 23 - Audits and Examinations                               A-21

     Section 24 - Dispute Resolution Procedures                         A-22

     Section 25 - Bona Fide Request Process for Further Unbundling      A-23

     Section 26 - Branding                                              A-25

     Section 27 - Taxes                                                 A-26

     Section 28 - Responsibility for Environmental Contamination        A-29

     Section 29 - Facilities                                            A-29

     Section 30 - Option to Obtain Services Under Other Agreements      A-30

     Section 31 - Other Services                                        A-30

     Section 32 - Provision and Use of Services                         A-31

     Section 33 - Selection of IntraLATA Telecomm. Service Provider     A-32

     Section 34 - Service Standards                                     A-32

     Section 35 - Subcontracting                                        A-33

     Section 36 - Amendments and Modifications                          A-33

     Section 37 - Severability                                          A-33

     Section 38 - Headings Not Controlling                              A-34

     Section 39 - Entire Agreement                                      A-34

     Section 40 - Counterparts                                          A-34

     Section 41 - Successors and Assigns                                A-34


    MCIm-BELL ATLANTIC INTERCONNECTION AGREEMENT - PENNSYLVANIA  PART A-ii
<PAGE>

  July 8, 1997                                                        PART A


     Section 42 - Good Faith Performance                               A-34

     Section 43 - Joint Work Product                                   A-34



   MCIm-BELL ATLANTIC INTERCONNECTION AGREEMENT-PENNSYLVANIA      PART A-iii
<PAGE>

July 8, 1997                                                            PART A


                            MCImetro/Bell Atlantic
                        INTERCONNECTION AGREEMENT 1997


     This MCImetro/Bell Atlantic Interconnection Agreement (the "Agreement"),
effective on the date the Pennsylvania Public Utility Commission approves this
Agreement, is entered into by and between MCImetro Access Transmission Services,
Inc. (" MCIm"), a Delaware corporation, and Bell Atlantic-Pennsylvania, Inc.
("Bell Atlantic" or "BA"), a Pennsylvania corporation, to establish the rates,
terms and conditions for the purchase and provision of Local Interconnection,
Local Resale, unbundled Network Elements and other services, all as set forth in
this Agreement (individually referred to as the "service" or collectively as the
"services") for the purpose of the purchasing Party's provision of Telephone
Exchange Service, Exchange Access Service, and/or Telecommunications Services.

     WHEREAS, on February 8, 1996, the Communications Act of 1934, 47 U.S.C. (S)
151, et seq., (the "Act") was amended by the Telecommunications Act of 1996; and

     WHEREAS, the Act places certain duties and obligations upon, and grants
certain rights to, Telecommunications Carriers and Local Exchange Carriers; and

     WHEREAS, the Parties are Telecommunications Carriers and Local Exchange
Carriers; and

     WHEREAS, the Act places certain duties and obligations upon, and grants
certain rights to, Incumbent Local Exchange Carriers, and Bell Atlantic is an
Incumbent Local Exchange Carrier; and

     WHEREAS, the Parties wish to interconnect their local exchange networks for
the provision of Telephone Exchange Service, for the transmission and
termination of local calls, so that subscribers of each can receive local calls
that originate on the other's network and place local calls that terminate on
the other's network, and for use in the provision of Exchange Access Service
("Local Interconnection"); and

     WHEREAS, MCIm wishes to purchase Telecommunications Services for resale
to others (" Local Resale" or "Services for Resale"), and Bell Atlantic is
willing to provide such service; and

     WHEREAS, MCIm wishes to purchase on an unbundled basis Network Elements,
and to use such services for the provision of Telecommunications Services to
others, and Bell Atlantic is willing to provide such services on the terms set
forth herein; and

     WHEREAS, the Parties intend the rates, terms and conditions of this
Agreement, and their performance of obligations thereunder, to comply with the
Act, the Rules and Regulations of the Federal Communications Commission ("FCC"),
and the orders, rules and regulations of the Pennsylvania Public Utility
Commission (the "Commission");




MCIm-BELL ATLANTIC INTERCONNECTION AGREEMENT - PENNSYLVANIA          PART A-1
<PAGE>

July 8, 1997                                                              PART A


      NOW, THEREFORE, in consideration of the premises and the mutual covenants
 of this Agreement, and intending to be legally bound by this Agreement, the
 Parties hereby covenant and agree as follows:

 PART A -- GENERAL TERMS AND CONDITIONS

 Section 1. Scope of this Agreement

  1.1 This Agreement, consisting of Parts A, B and C, specifies the rights and
obligations of each Party with respect to the purchase and sale of Local
Interconnection, Local Resale and Network Elements. This PART A sets forth the
general terms and conditions governing this Agreement. Capitalized terms used in
this Agreement shall have the meanings defined in PART B -- DEFINITIONS, or as
otherwise elsewhere defined throughout this Agreement. PART C sets forth, among
other things, descriptions of the services, pricing, technical and business
requirements, and physical and network security requirements.

          LIST OF ATTACHMENTS COMPRISING PART C:

          I.     Price Schedule
          II.    Local Resale
          III.   Network Elements
          IV.    Interconnection
          V.     Collocation
          VI.    Rights of Way
          VII.   Number Portability
          VIII.  Business Process Requirements
          IX.    Security Requirements
          X.     Performance Reporting

      1.2 Bell Atlantic shall provide the services in any Technically Feasible
      Combination requested by MCIm, pursuant to the terms of this Agreement and
      in accordance with the requirements of Applicable Law, or where
      appropriate, the Bona Fide Request ("BFR") process set forth in Section
      25 (BFR Process for Further Unbundling)of Part A, except that Local Resale
      shall be provided pursuant to Attachment II. Neither Party shall
      discontinue or refuse to provide any service provided or required
      hereunder, except in accordance with the terms hereof, without the other
      Party's written agreement. Bell Atlantic shall not reconfigure,
      reengineer or otherwise redeploy its network in a manner which would
      impair MCIm's ability to offer Telecommunications Services in the manner
      contemplated by this Agreement, the Act or the FCC's Rules and Regulations
      without providing notice of Network Changes in accordance with the Act
      and FCC Rules and Regulations.

      1.3 The Parties acknowledge that some of the services, facilities and
      arrangements provided pursuant to this Agreement are or will be available
      under and subject to the


  MCIm-BELL ATLANTIC INTERCONNECTION AGREEMENT - PENNSYLVANIA          PART A-2
<PAGE>

July 8, 1997                                                            PART A


   terms of the federal or state Tariffs of the Party providing them. To the
   extent that a Tariff of a Party applies to any service, facility or
   arrangement provided pursuant to this Agreement, the following shall apply:

   1.3.1 The rates and charges set forth in Attachment I shall remain
   fixed for the term of this Agreement or until superseded by such rates
   (whether interim or permanent) as may be applied by the Commission,
   notwithstanding that either of such rates may be different from those set
   forth in any effective, pending or future Tariff of the providing Party,
   (including any changes or modifications to any such Tariff--or any new
   Tariff--filed after the Effective Date of this Agreement); provided, however,
   this Section 1.3.1 shall remain subject to Section 1.3.3.

   1.3.2 This Agreement and any applicable Tariffs of either Party shall be
   construed whenever possible to avoid any conflict between them. The fact that
   a condition, term, right or obligation appears in the Agreement and not in a
   Tariff, or in a Tariff but not in the Agreement, shall not be interpreted as,
   or deemed grounds for finding, a conflict for the purposes of this Section
   1.3.

   1.3.3 Any change or modification to any Tariff (including any Tariff filed
   after the Effective Date hereof)filed by either Party that materially and
   adversely impacts the provision or receipt of services hereunder or which
   materially and adversely alters the terms hereof shall only be effective
   against the other Party to the extent permitted by: (i) that Party's written
   consent; or (ii) an affirmative order of the Commission. Each Party shall
   file any required Tariff revisions, modifications or amendments in order to
   comply with Applicable Law and to continue performance of this Agreement in a
   lawful manner.

     1.4 Construction

   1.4.1 For purposes of this Agreement, certain terms have been defined in Part
   B or elsewhere in this Agreement. These terms will have the meanings stated
   in this Agreement, which may differ from, or be in addition to, the normal
   definition of the defined word. A defined word intended to convey the meaning
   stated in this Agreement is capitalized when used. Other terms that are
   capitalized, and not defined in this Agreement, shall have the meaning stated
   in the Act.

   1.4.2 Unless the context clearly indicates otherwise, any defined term which
   is defined or used in the singular shall include the plural, and any defined
   term which is defined or used in the plural shall include the singular.

    1.4.3 The words "shall" and "will" are used interchangeably throughout this
    Agreement and the use of either indicates a mandatory requirement. The use
    of one or the other shall not mean a different degree of right or obligation
    for either Party.


MCIm-BELL ATLANTIC INTERCONNECTION AGREEMENT - PENNSYLVANIA          PART   A-3
<PAGE>

July 8, 1997                                                            PART A


          1.4.4 Conflicts among terms in Parts A and B of this Agreement, the
          Attachments and the Exhibits thereto, and the Tariffs shall be
          resolved in accordance with the following order of precedence, where
          the document identified in Subsection "(i)" shall have the highest
          precedence: (i) Parts A and B of this Agreement; (ii) the Attachments
          and the Exhibits thereto; and (iii) the Tariffs. The fact that a
          matter is addressed in one of these documents, but not in another,
          shall not constitute a conflict for purposes of this Section 1.4.4.

Section 2. Regulatory Approvals

     2.1 The Parties shall promptly submit this Agreement, and any amendment or
     modification hereof, to the Commission for approval in accordance with
     Section 252 of the Act. Following such submission, the Parties shall submit
     the Agreement to any other applicable governmental entity for any requisite
     approvals. In the event any governmental authority or agency rejects any
     provision hereof, the Parties shall negotiate promptly and in good faith
     such revisions as may reasonably be required to achieve approval.

     2.2 In the event the FCC or the Commission promulgates rules or
     regulations, or issues orders, or a court of competent jurisdiction issues
     orders, which make unlawful any provision of this Agreement, or which
     materially reduce or alter the services required by statute or regulations
     and embodied in this Agreement, then the Parties shall negotiate promptly
     and in good faith in order to amend the Agreement to substitute contract
     provisions which conform to such rules, regulations or orders. In the event
     the Parties cannot agree on an amendment within thirty (30) days after the
     date any such rules, regulations or orders become effective, then the
     Parties shall resolve their dispute under the applicable procedures set
     forth in Section 24 (Dispute Resolution Procedures) hereof.

     2.3 The Parties intend that any services requested by either Party relating
     to the subject matter of this Agreement that are not offered hereunder will
     be incorporated into this Agreement by amendment upon agreement by the
     Parties.

     2.4 In the event that any legally effective legislative, regulatory,
     judicial or other legal action materially affects any material terms of
     this Agreement, or the ability of MCIm or Bell Atlantic to perform any
     material terms of this Agreement, MCIm or Bell Atlantic may, on thirty
     (30)days written notice (delivered not later than thirty (30) days
     following the date on which such action has become legally binding or has
     otherwise become legally effective) require that such terms be
     renegotiated, and the Parties shall renegotiate in good faith such mutually
     acceptable new terms as may be required.

     2.5 When this Agreement is filed with the Commission for approval, the
     Parties will request that the Commission: (a) approve the Agreement, and
     (b) refrain from taking any action to change, suspend or otherwise delay
     implementation of the Agreement.



MClm-BELL ATLANTIC INTERCONNECTION AGREEMENT - PENNSYLVANIA           PART  A-4

                                       4
<PAGE>

July 8, 1997                                                            PART A


     2.6 Each Party shall be responsible for obtaining and keeping in effect all
     FCC, Commission, franchise authority and other governmental approvals, that
     may be required in connection with the performance of its respective
     obligations under this Agreement.

Section 3. Term of Agreement

     3.1 This Agreement shall become effective as of the Effective Date stated
     above and, except as otherwise provided in this Agreement, shall remain in
     effect until August 31, 2000, and thereafter until terminated as provided
     in this Agreement. At least one hundred eighty (180) days before the term
     expires, either Party shall file with the Commission any request for an
     extension of that term, and shall on the same day provide notice to the
     other Party. At least one hundred fifty (150) days before the term expires,
     the other Party shall respond to the requested extension. If for any reason
     a new agreement has not been reached by the end of the three-year term, the
     existing interconnection agreement shall continue, month-to-month, under
     the same terms and conditions, subject to a true-up, until resolved by the
     Commission.

     3.2 This Agreement shall be effective between the Parties as of the
     Effective Date, notwithstanding the pendency of proceedings challenging the
     Commission's approval of the Agreement.

     3.3 Each Party recognizes that the services being provided under this
     Agreement at the time of its termination may need to be continued without
     interruption thereafter, and that upon such termination, either Party may
     itself provide or retain another vendor to provide comparable services.
     Each Party agrees to cooperate in an orderly and efficient transition to
     the other Party or another vendor such that the level and quality of the
     services are not degraded, and to exercise reasonable efforts to effect an
     orderly and efficient transition.

     3.4 Unless a service is required to be offered by a Party under Applicable
     Law, either Party may terminate any service provided under this Agreement
     upon thirty (30) days prior written notice to the other Party unless a
     different notice period or different conditions are specified in this
     Agreement (including, but not limited to, in an applicable Tariff or
     Applicable Law) for termination of such service, in which event such
     specified period and/or conditions shall apply. Upon termination of its
     purchase of a service by the purchasing Party, the purchasing Party shall
     pay any applicable termination charges specified in this Agreement. Upon
     termination of a Local Resale service by Bell Atlantic, co, MCIm shall be
     entitled to continue providing the terminated service to MCIm's
     subscribers on a grandfathered basis to the same extent, and subject to
     the same terms and conditions, as would apply to such subscribers if they
     had been subscribers of Bell Atlantic for the terminated service at the
     time the service is terminated, and Bell Atlantic shall continue to
     provide such services to MCIm on the same basis.

     3.5 Following the expiration of this Agreement, this Agreement shall remain
    in effect as to any Expiring Service for the remainder of any contract
    period applicable to such Expiring Service at the time of the expiration of
    this Agreement. If an Expiring Service

MCIm-BELL ATLANTIC INTERCONNECTION AGREEMENT - PENNSYLVANIA             PART A-5

                                       5
<PAGE>

 July 8, 1997                                                            PART A


       is terminated prior to the expiration of the contract period applicable
       to such Expiring Service, MCIm shall pay any termination charge provided
       for in this Agreement, in an applicable Tariff, or in the contract
       applicable to the Expiring Service. Following expiration of the
       applicable contract period for an Expiring Service, the Expiring Service,
       until terminated, shall be subject to: (i) any effective agreement
       superseding this Agreement; or (ii) to the extent such Expiring Service
       is not covered by such superseding agreement, applicable Tariffs. For the
       purposes of this Section 3.5, "Expiring Service" means: (a) any Local
       Resale service that, upon expiration of the term of this Agreement, is
       being provided under this Agreement and is subject to a remaining
       contract period greater than one (1) month; or (b) any Local Resale
       service: (i) for which an order has been submitted and accepted pursuant
       to this Agreement prior to the expiration of this Agreement but such
       service is not being provided at the expiration of this Agreement; and
       (ii) that is subject to an initial contract period which is greater than
       one (1) month.

 Section 4. Charges and Payment

       4.1 In consideration of the services provided under this Agreement, the
       purchasing Party shall pay the charges set forth in Attachment I. The
       billing and payment procedures for charges incurred by a purchasing Party
       hereunder are set forth in Attachment VIII.

 Section 5. Assignment

       5.1 Any assignment or delegation by either Party to any non-affiliated
       entity of any right, obligation or duty, or of any other interest
       hereunder, in whole or in part, without the prior written consent of the
       other Party shall be void (except the assignment of a right to moneys due
       or to become due). A Party assigning or delegating this Agreement or any
       right, obligation, duty or other interest hereunder to an Affiliate shall
       provide written notice to the other Party. All obligations and duties of
       any Party under this Agreement shall be binding on all successors in
       interest and assigns of such Party. No assignment or delegation hereof
       shall relieve the assignor of its obligations under this Agreement.

       5.2 If any obligation of either Party is performed by a subcontractor or
       Affiliate, such Party shall remain fully responsible for the performance
       of this Agreement in accordance with its terms.

 Section 6. Compliance with Laws

       6.1 Each Party shall perform terms, conditions and operations under this
       Agreement in a manner that complies with all Applicable Law, including
       all regulations and judicial or regulatory decisions of all duly
       constituted governmental authorities of competent jurisdiction. Each
       Party shall be responsible for obtaining and keeping in effect all FCC,
       state regulatory commission, franchise authority and other regulatory
       approvals that may be required in connection with the performance of its
       obligations under this Agreement. Each Party shall reasonably cooperate
       with the other in obtaining and maintaining any approvals required by
       this Section. In the event the Act or FCC Rules and Regulations

 MCIm-BELL ATLANTIC INTERCONNECTION AGREEMENT -PENNSYLVANIA            PART A-6

                                       6
<PAGE>

July 8, 1997                                                           PART A


    applicable to this Agreement are held invalid, this Agreement shall
    survive, and the Parties shall promptly renegotiate any provisions of this
    Agreement which, in the absence of such invalidated Act, Rule or
    Regulation, are insufficiently clear to be effectuated.

    6.2 Except as otherwise specified in this Agreement, each Party shall be
    responsible for: (i) all costs and expenses it incurs in complying with its
    obligations under this Agreement; and (ii) the development, modification,
    technical installation and maintenance of any systems or other
    infrastructure which it requires to comply with and to continue complying
    with its responsibilities and obligations under this Agreement.

Section 7. Governing Law

    7.1 The validity of this Agreement, the construction and enforcement of its
    terms, and the interpretation of the rights and duties of the Parties, shall
    be governed by the Act and the laws of the Commonwealth of Pennsylvania,
    without regard to its conflicts of laws rules.

Section 8. Relationship of Parties

    8.1 Each Party is an independent contractor, and has and hereby retains the
    right to exercise full control of and supervision over its own performance
    of its obligations under this Agreement.

    8.2 Each Party retains full control over the employment, direction,
    compensation and discharge of all of its employees, agents and contractors
    assisting in the performance of its obligations under this Agreement. Each
    Party will be solely responsible for all matters relating to payment of its
    employees, agents and contractors, and payment of Social Security and other
    taxes in association with such employees, agents and contractors, and
    withholding and remittance of taxes from such employees, agents and
    contractors.

    8.3 Nothing contained within this Agreement shall:

          8.3.1 Make either Party the agent, servant or employee, of the other
          Party;

          8.3.2 Grant either Party the authority to enter into a contract on
          behalf of, or  otherwise legally bind, the other Party in any
          way;

          8.3.3 Create a partnership, joint venture, or other similar
          relationship between the Parties; or

          8.3.4 Grant to either Party a franchise, distributorship, or
          similar interest.

    8.4 The relationship of the Parties under this Agreement is a non-exclusive
    relationship. Each Party shall have the right:



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          8.4.1 To provide services to be provided by it under this Agreement to
          persons other than the other Party; and

          8.4.2 To purchase services which can be purchased by it under this
          Agreement from persons other than the other Party.

Section 9. No Third Party Beneficiaries

     9.1 Except as may be specifically set forth in this Agreement, this
     Agreement does not provide and shall not be construed to provide any third
     parties (including, but not limited to, subscribers or subcontractors of a
     Party) with any right, remedy, claim, reimbursement, cause of action, or
     other privilege. The provisions of this Agreement are for the benefit of
     the Parties hereto and not for any other person, provided, however, that
     this shall not be construed to prevent either Party from providing its
     Telecommunications Services to any entities.

Section 10. Intellectual Property Rights

     10.1 Any intellectual property which originates from or is developed by a
     Party shall remain in the exclusive ownership of that Party. Except for a
     limited license to use a Party's patents or copyrights to the extent
     necessary for the Parties to use any facilities or equipment (including
     software) or to receive any service solely as provided under this
     Agreement, no license in patent, copyright, trademark or trade secret, or
     other proprietary or intellectual property right now or hereafter owned,
     controlled or licensable by a Party, is granted to the other Party or shall
     be implied or arise by estoppel.

     10.2 Bell Atlantic shall indemnify MCIm with respect to MCIm's use,
     pursuant to the terms of this Agreement, of intellectual property
     associated with any new Bell Atlantic network equipment or software
     acquisitions. Bell Atlantic warrants that it will not enter into any
     licensing agreements with respect to new Bell Atlantic network equipment or
     software acquisitions that contain provisions that would disqualify MCIm
     from using or interconnecting with such network equipment or software
     pursuant to the terms of this agreement. Bell Atlantic also warrants that
     it has not and will not intentionally modify any existing licensing
     agreements for existing network equipment or software in order to
     disqualify MCIm from using or interconnecting with such network equipment
     or software, pursuant to the terms of this agreement. To the extent that
     the providers of equipment or software in Bell Atlantic's network provide
     Bell Atlantic with indemnities covering intellectual property liabilities
     and those indemnities allow a flow through of protection to third parties,
     Bell Atlantic shall flow those indemnity protections through to MCIm. Bell
     Atlantic will inform MCIm of any pending or threatened intellectual
     property claims relating to Bell Atlantic's network of which Bell Atlantic
     is aware and will update that notification periodically as needed, so that
     MCIm receives maximum notice of any intellectual property risks it might
     want to address. Notwithstanding any part of this Section 10, MCIm retains
     the right to pursue legal remedies against Bell Atlantic if Bell Atlantic
     is at fault in causing intellectual property liability to MCIm.


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July 8, 1997                                                              P.


          10.2.1 For purposes of Section 10.2, Bell Atlantic's obligation to
          indemnify include the obligation to indemnify and hold MCIm harmless
          from and against any loss, cost, expense or liability arising out of a
          claim that MCIm's use, pursuant to the terms of this Agreement, of
          such new Bell Atlantic network equipment or software infringes the
          intellectual property rights of a third party. Moreover, should any
          such network equipment or software or any portion there provided by
          Bell Atlantic hereunder become, or, in Bell Atlantic's reasonable
          opinion, be likely to become, the subject of a claim of infringement,
          or should MCIm's use thereof be finally enjoined, Bell Atlantic shall,
          at its immediate expense and at its choice:

               10.2.1.1 Procure for MCIm the right to continue using such
               material; or

               10.2.1.2 Replace or modify such material to make it non-
               infringing provided such replacement or modification is
               functionally equivalent.

     10.3 Unless otherwise mutually agreed upon, neither Party shall publish or
     use the other Party's logo, trademark, or service mark in any product,
     service, advertisement, promotion, or any other publicity matter, except
     that nothing herein shall prohibit lawful comparative advertising or
     comparative marketing.

Section 11. Indemnification

     11.1 Each Party agrees to release, indemnify, defend and hold harmless the
     other Party from and against all losses, claims, demands, damages,
     expenses, suits or other actions, or any liability whatsoever, including,
     but not limited to, costs and attorneys' fees (collectively, a "Loss")
     incurred by the indemnified Party to the extent that such Loss is: (a)
     suffered, made, instituted, or asserted by any other person, relating to
     personal injury to or death of any person, or for loss, damage to, or
     destruction of real and/or personal property, whether or not owned by
     others, incurred during the term of this Agreement and to the extent
     legally caused by the acts or omissions of the indemnifying Party,
     regardless of the form of action; or (b) suffered, made, instituted, or
     asserted by the indemnifying Party's own customer(s) against the
     indemnified Party arising out of the indemnified Party's provision of
     services to the indemnifying Party under this Agreement, except to the
     extent the Loss arises from a breach of this Agreement by the indemnified
     Party. Notwithstanding the foregoing indemnification, nothing in this
     Section 11 shall affect or limit any claims, remedies, or other actions the
     indemnifying Party may have against the indemnified Party under this
     Agreement, any other contract, or any applicable Tariff(s), regulations or
     laws.

     11.2 MCIm shall indemnify, defend and hold harmless Bell Atlantic, Bell
     Atlantic's Affiliates, and the directors, officers and employees of
     Bell Atlantic and Bell Atlantic's Affiliates, from and against any
     claim, demand, suit, action, judgment, liability, damage or loss (including
     reasonable costs, expenses and attorneys' fees on account thereof), that
     arises out of or results from: (i) MCIm's negligent use or occupancy of a
     Bell Atlantic


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     NID; (ii) wiring, facilities, equipment or other apparatus, negligently
     installed by MCIm in or on a Bell Atlantic NID, or negligently connected by
     MCIm to a Bell Atlantic NID; or (iii) the negligent acts or omissions of
     MCIm, MCIm's Affiliates, or the employees, agents or contractors of MCIm or
     MCIm's Affiliates, in connection with a Bell Atlantic NID. Where the NID is
     not used by Bell Atlantic or another Telecommunications Carrier (except
     MCIm) to provide service to the premise, MCIm shall have the burden, as
     between Bell Atlantic and MCIm, to rebut the presumption that the claim,
     demand, suit, action, judgment, liability, damage or loss arises from
     wiring, facilities, equipment or other apparatus, negligently installed by
     MCIm in or on a Bell Atlantic NID, or negligently connected by MCIm to a
     Bell Atlantic NID. For the purposes of this Section 11.2, references to
     "negligence" or "negligently" shall be read to also encompass acts of gross
     negligence and/or intentional misconduct.

     11.3 The indemnification provided herein shall be conditioned upon:

          11.3.1 The indemnified Party shall promptly notify the indemnifying
          Party of any action taken against the indemnified Party relating to
          the indemnification, provided that failure to notify the indemnifying
          Party shall not relieve it of any liability it might otherwise have
          under this Section 11 to the extent it was not materially prejudiced
          by such failure of notification.

          11.3.2 The indemnifying Party shall have sole authority to defend any
          such action, including the selection of legal counsel, and the
          indemnified Party may engage separate legal counsel only at its sole
          cost and expense. In the event the indemnifying Party does not accept
          the defense of any such action, the indemnified Party shall have the
          right to employ counsel for its own defense at the expense of the
          indemnifying Party.

          11.3.3 In no event shall the indemnifying Party settle or consent to
          any judgment pertaining to any such action without the prior written
          consent of the indemnified Party, which consent shall not be
          unreasonably withheld.

          11.3.4 In any action for which indemnity is sought, the indemnified
          Party shall assert any and all provisions in applicable Tariffs that
          limit liability to third parties as a bar to any recovery by the third
          party claimant in excess of applicable limitations of liability.

          11.3.5 The indemnified Party shall offer the indemnifying Party all
          reasonable cooperation and assistance in the defense of any such
          action.

  Section 12. Limitation of Liability

     12.1 Neither Party shall be liable to the other for any indirect,
     incidental, special or consequential damages arising out of or related to
     this Agreement or the provision of service hereunder. Notwithstanding the
     foregoing limitation, a Party's liability shall not


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   be limited by the provisions of this Section 12 in the event of its willful
   or intentional misconduct, including gross negligence. Bell Atlantic shall be
   liable to MCIm for lost revenues resulting from Bell Atlantic's breach of
   this Agreement only to the same extent that Bell Atlantic's Tariffs provide
   liability for Bell Atlantic end user subscribers' revenue losses. A Party's
   liability shall not be limited with respect to its indemnification
   obligations.

Section 13. Warranties

   13.1 As more specifically set forth herein, each Party shall perform its
   obligations hereunder at Parity, as defined in Part B of this Agreement,
   which definition is intended to embody the performance provisions set forth
   in 47 U.S.C. (S) 251, and any implementing regulations thereunder, as those
   provisions may apply to the Party and obligation in question.

   13.2 As more specifically set forth in Attachment II, Bell Atlantic shall
   provide Local Resale at Parity.

   13.3 As more specifically set forth in Attachment III, Bell Atlantic shall
   provide Network Elements at Parity.

   13.4 As more specifically set forth in Attachment IV, Bell Atlantic shall
   provide Interconnection at Parity and on a Non-Discriminatory Basis. MCIm
   shall provide Interconnection on a Non-Discriminatory Basis.

   13.5 As more specifically set forth in Attachment V, Bell Atlantic shall
   provide Collocation in accordance with the legally effective rules,
   regulations and orders of the FCC and the Commission.

   13.6 As more specifically set forth in Attachment VI, Bell Atlantic shall
   provide Non-Discriminatory access to poles, ducts, conduits, and ROW owned or
   controlled by Bell Atlantic, in accordance with the requirements of section
   224 of the Act and legally effective rules, regulations and orders of the FCC
   and the Commission.

   13.7 As more specifically set forth in Attachment VII, Bell Atlantic and MCIm
   shall provide Interim Number Portability and Number Portability in accordance
   with the legally effective rules, regulations and orders of the FCC and the
   Commission.

   13.8 As more specifically set forth in Attachment VIII, Bell Atlantic and
   MCIm shall meet Business Process Requirements.

   13.9 As more specifically set forth in Attachment VIII, Bell Atlantic shall
   provide Non-Discriminatory access to telephone numbers for as long as Bell
   Atlantic remains the code administrator for the North American Numbering
   Plan.



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July 8, 1997                                                             PART A


   13.10 As more specifically set forth in Attachment VIII, Bell Atlantic and
   MCIm shall provide dialing parity in accordance with the legally effective
   rules, regulations and orders of the FCC and the Commission.

   13.11 As more specifically set forth in Attachment IX, Bell Atlantic and MCIm
   shall meet security requirements, to the extent applicable to the security
   requirement in question.

   13.12 As more specifically set forth in Attachment X, Bell Atlantic shall
   provide performance reporting.

   EXCEPT AS SET FORTH IN THIS AGREEMENT, NEITHER PARTY MAKES ANY WARRANTIES
   WITH RESPECT TO ITS SERVICES, WHETHER EXPRESS OR IMPLIED, WRITTEN OR ORAL, IN
   FACT OR IN LAW. THE WARRANTIES SET FORTH IN THIS AGREEMENT ARE A PARTY'S
   EXCLUSIVE WARRANTIES WITH RESPECT TO ITS SERVICES AND ARE IN LIEU OF ALL
   OTHER WARRANTIES, EXPRESS OR IMPLIED, WRITTEN OR ORAL, IN FACT OR IN LAW.
   EACH PARTY DISCLAIMS ANY AND ALL OTHER WARRANTIES WITH RESPECT TO ITS
   SERVICES, INCLUDING  , BUT NOT LIMITED TO, WARRANTIES OF MERCHANTABILITY AND
                                              ---------------------------------
   FITNESS FOR A PARTICULAR PURPOSE AND WARRANTIES AGAINST INFRINGEMENT.
   --------------------------------

Section 14. Notices

   14.1 Except as otherwise provided herein, or where context or services
   dictate that immediate notice be given, all notices or other communication
   hereunder shall be deemed to have been duly given when made in writing and
   delivered in person or deposited in the United States mail, certified mail,
   postage prepaid, return receipt requested and addressed as follows:

         To MCIm:           MCImetro Access Transmission Services, Inc.
                            Attention: Vice President
                            1650 Tysons Boulevard
                            McLean, VA 22102

         Copy to:           General Counsel
                            MCI Communications Corporation
                            1801 Pennsylvania Ave., N.W.
                            Washington, DC 20006

         To Bell Atlantic:  Bell Atlantic Network Services, Inc.
                            Attention: Director, Interconnection Initiatives
                            1320 North Courthouse Road, 9th Floor
                            Arlington, VA 22201


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July 8, 1997                                                              PART A


          copy to:       Legal Department
                         Bell Atlantic Network Services, Inc.
                         Attention: Counsel, Carrier Services
                         1320 North Courthouse Road, 8th Floor
                         Arlington, VA 22201

  If personal delivery is selected to give notice, a receipt of such delivery
  shall be obtained. The address to which notices or communications may be given
  to either Party may be changed by written notice given by such Party to the
  other pursuant to this Section 14.

Section 15. Technical References

   15.1 The Parties agree that the Bell Atlantic technical references set forth
   in Appendix I to this Part A (Technical Reference Schedule) provide the
   current technical specifications for the services offered by Bell Atlantic
   under this Agreement. Bell Atlantic reserves the right with reasonable
   notification to revise its technical references for any reason including, but
   not limited to, laws or regulations, conformity with updates and changes in
   standards promulgated by various agencies, utilization of advances in the
   state of technical arts, or the reflection of changes in the design of any
   facilities, equipment, techniques, or procedures described or referred to in
   the technical references. Notification of changes that are made to the
   underlying Bell Atlantic services will; be made in conformance with the
   requirements of Section 251(c)(5), Notice of Changes, of the Act, and the
   FCC's Rules and Regulations. The Parties acknowledge that the general
   technical references set forth below contain certain generally accepted
   industry guidelines for particular interface and performance parameters for
   telecommunications equipment used by LECs in the United States. Such accepted
   technical references may be used by LECs to specify suitable equipment and
   facilities components for use in their respective networks, to assure
   interoperability between components that collectively comprise such networks,
   and to specify the interface characteristics and typical end-to-end
   performance of certain services.

   15.2 The Parties acknowledge that they and their vendors and suppliers derive
   guidance from such technical references, and make reasonable efforts to
   conform to them. Requests for specific performance, functionality, or
   capabilities not applied in a Party's network should be handled using the BFR
   process set forth in Section 25 (BFR Process for Further Unbundling) of this
   Part A.

   15.3 If one or more of the technical requirements set forth in Appendix I are
   in conflict, the Parties shall reasonably agree on which requirement shall
   apply.

   15.4 The Parties agree that they each intend, to the extent technically
    feasible and commercially reasonable, to conform generally to industry
    standards applicable to the Parties set by the OBF, within a reasonable time
    after publication of final standards. With respect to OBF and other industry
    standards, the Parties agree that they will negotiate in good faith the
    applicability, technical feasibility and commercial


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July 8, 1997                                                             PART A


   reasonableness for implementation of such standards for services and
   arrangements under the Agreement.

Section 16. Remedies

    16.1 The obligations of the Parties and the services offered under this
    Agreement may be unique. Accordingly, in addition to any other available
    rights or remedies, either Party may sue in equity for specific performance.

    16.2 In the event either Party fails to switch a subscriber to the other
    Party's service as requested through a service request from the other Party,
    within any applicable intervals set forth in this Agreement or required by
    Applicable Law, or erroneously switches the other Party's subscriber away
    from that Party, then such act (including the continued provision of
    Telecommunications Services to such subscriber by the Party erroneously
    switching or failing to switch) shall be deemed an improper change in
    subscriber carrier selection commencing with the time at which such Party
    erroneously failed to switch such subscriber, or erroneously switched such
    subscriber. If such an improper change in subscriber carrier selection
    should occur, the rights and obligations of the Parties shall be determined
    in accordance with the regulations pertaining to such conduct on the part of
    Interexchange Carriers as set forth in the FCC's Rules and Regulations, Part
    64, Subpart K, as these may be amended from time to time. For the purpose of
    this Section, Bell Atlantic shall be deemed an Interexchange Carrier.

    16.3 At such time as the FCC or other competent regulatory body adopts
    regulations implementing 47 U.S.C. Section 258 or otherwise adopt
    regulations applicable to illegal or improper changes in local service, then
    such regulations shall supersede those applicable to Interexchange Carriers
    for the purposes of this Section 16.

    16.4 Unless otherwise specifically provided hereunder, all rights of
    termination, cancellation or other remedies prescribed in this Agreement, or
    otherwise available, are cumulative and are not intended to be exclusive of
    other remedies to which the injured Party may be entitled at law or equity.

Section 17 Waivers

    17.1 A failure or delay of either Party (including any course of dealing or
    course of performance) to enforce any of the provisions of this Agreement,
    or any right or remedy available under this Agreement or at law or in
    equity, or to require performance of any of the provisions of this
    Agreement, or to exercise any option provided under this Agreement, shall in
    no way be construed to be a waiver of such provisions, rights, remedies or
    options.

    17.2 Waiver by either Party of any default by the other Party shall not be
    deemed a waiver of any other default.



MCIm-BELL ATLANTIC INTERCONNECTION AGREEMENT - PENNSYLVANIA PART            A-14

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July 8, 1997                                                            PART A


Section 18. Survival

     18.1 Any liabilities or obligations of a Party for acts or omissions
     occurring prior to the expiration, cancellation or termination of this
     Agreement, any obligation of a Party under any provision for
     indemnification or defense (including, but not limited to, any of Sections
     10, 11, 12, 23, 24, 28 and 29), Section 3, "Termination", Section 22,
     "Confidential Information", any provision for limitation of liability, and
     any obligation of a Party under any other provisions of this Agreement
     which, by their terms, are contemplated to survive (or to be performed
     after) expiration, cancellation or termination of this Agreement, shall
     survive the expiration, cancellation or termination of the Agreement, but
     solely to the minimum extent necessary to effectuate such provisions or
     complete such performance.

Section 19. Force Majeure

     19.1 Except as otherwise specifically provided in this Agreement
     (including, by way of illustration, circumstances where a Party is required
     to implement disaster recovery plans to avoid delays or failure in
     performance and the implementation of such plans was designed to avoid the
     delay or failure in performance), neither Party shall be liable for any
     delay or failure in performance of any part of this Agreement by it caused
     by acts or failures to act of the United States of America or any state,
     district, territory, political subdivision, or other governmental entity,
     acts of God or a public enemy, strikes, labor slowdowns, or other labor
     disputes, but only to the extent that such strikes, labor slowdowns, or
     other labor disputes also affect the performing Party, fires, explosions,
     floods, embargoes, earthquakes, volcanic actions, unusually severe weather
     conditions, wars, civil disturbances, or other causes beyond the reasonable
     control of the Party claiming excusable delay or other failure to perform
     ("Force Majeure Condition"). In the event of any such excused delay in the
     performance of a Party's obligation(s) under this Agreement, the due date
     for the performance of the original obligation(s) shall be extended by a
     term equal to the time lost by reason of the delay. In the event of such
     delay, the delaying Party shall perform its obligations at a performance
     level no less than that which it uses for its own operations. In the event
     of such performance delay or failure by Bell Atlantic, Bell Atlantic
     agrees to resume performance at Parity and in a Non-Discriminatory manner.

     19.2 If any Force Majeure Condition occurs, the Party whose performance
     fails or is delayed because of such Force Majeure Condition shall give
     prompt notice to the other Party, and upon cessation of such Force Majeure
     Condition, shall give like notice and commence performance hereunder as
     promptly as reasonably practicable.

     19.3 Notwithstanding Section 19.1, no delay or other failure by a Party to
     perform shall be excused pursuant to this Section by the delay or failure
     of a Party's subcontractors, materialmen, or suppliers to provide products
     or services to the Party, unless such delay or failure is itself the
     product of a Force Majeure Condition, and such products or services cannot
     be obtained by the Party from other persons on commercially reasonable
     terms.


  MCIm-BELL ATLANTIC INTERCONNECTION AGREEMENT - PENNSYLVANIA          PART A-15

                                       15
<PAGE>

July 8, 1997                                                            PART A


Section 20. Publicity

     20.1 Neither Party shall produce, publish, or distribute any press release
     or other publicity referring to the other Party in connection with this
     Agreement, without the prior written approval of the other Party, which
     approval shall not be unreasonably withheld.

Section 21. Default and Termination

     21.1 If a Party ("Breaching Party") materially breaches a material
     provision of this Agreement (other than an obligation to make payment of
     any amount billed under this Agreement), and such breach continues for
     more than thirty (30) days after written notice thereof from the other
     Party ("Injured Party"), then, except as otherwise required by Applicable
     Law, the Injured Party shall have the right, upon notice to the Breaching
     Party, to terminate or suspend this Agreement and/or the provision of
     services.

     21.2 If a purchasing Party fails to make a payment of any amount billed
     under this Agreement by the due date stated on the providing Party's bill
     and such failure continues for more than thirty (30) days after written
     notice thereof from the providing Party, then, except as provided in
     Section 21.3 or as otherwise required by Applicable Law, the providing
     Party shall have the right, upon notice to the purchasing Party, to
     terminate or suspend this Agreement and/or the provision of services.

     21.3 Billing Disputes.

          21.3.1 If a billing dispute arises concerning any charges billed
          pursuant to this Agreement by a providing Party to a purchasing
          Party, payments withheld or paid pending settlement of the dispute
          shall be subject to interest at the rate set forth in Bell Atlantic's
          interstate access tariff.

          21.3.2 If the purchasing Party pays the bill in full by the payment
          due date and later initiates a billing dispute pursuant to Attachment
          VIII, Section 3.1.9, interest will apply as follows:

               21.3.2.1 If the billing dispute is resolved in favor of the
               purchasing Party, the purchasing Party shall receive a credit
               from the providing Party. This credit will be an amount equal
               to the disputed amount, plus interest at the rate set forth in
               Bell Atlantic's interstate access tariff. This amount will apply
               from the date of the purchasing Party's payment through the date
               on which the purchasing Party receives payment of the
               disputed amount and accrued interest from the providing Party.

               21.3.2.2 If the dispute is resolved in favor of the providing
               Party, neither a late payment charge nor an interest charge is
               applicable.



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<PAGE>

July 8, 1997                                                             PART A


  21.3.3 If the purchasing Party withholds payment on the bill (in full or in
  part) and initiates a billing dispute pursuant to Attachment VIII, Section
  3.1.9, interest will apply as follows:

               21.3.3.1 If the billing dispute is resolved in favor of the
               providing Party, the purchasing Party shall pay the providing
               Party a payment equal to the amount withheld by the purchasing
               Party, plus interest at the rate set forth in Bell Atlantic's
               interstate access tariff. This amount will apply from the payment
               due date through the date on which the providing Party receives
               payment of the disputed amount and accrued interest from the
               purchasing Party.

               21.3.3.2 If the dispute is resolved in favor of the purchasing
               Party, neither a late payment charge nor an interest charge is
               applicable.

     21.4 Notwithstanding the foregoing, if a Party's material breach is for any
     failure to perform in accordance with this Agreement which materially and
     adversely affects the provision of service of the non-breaching Party's
     subscribers, the non-breaching Party shall give notice of the breach and
     the breaching Party shall cure such breach within ten (10) days or within a
     period of time equivalent to the applicable interval required by this
     Agreement, whichever is shorter, and if the breaching Party does not, the
     non-breaching Party may, as its sole option, terminate this Agreement, or
     any parts hereof. The nonbreaching Party shall be entitled to pursue all
     available legal and equitable remedies for such breach.

     21.5 MCIm may terminate this Agreement in whole or in part at any time for
     any reason upon sixty (60) days prior written notice, except with respect
     to termination of any particular service(s), in which case, upon thirty
     (30) days prior written notice. MCIm's sole liability for such termination
     shall be payment of amounts due for services provided up to the date of
     termination, unless otherwise provided for in this Agreement or in a Tariff
     providing a termination liability or minimum term for a service.

     21.6 In the event of any termination under this Section 21 and, if
     applicable, pursuant to Section 3.3, Bell Atlantic agrees to provide for an
     uninterrupted transition of the services Bell Atlantic is providing to MCIm
     at the time of termination to MCIm or another vendor designated by MCIm,
     and MCIm agrees to provide for an uninterrupted transition of services MCIm
     is providing to Bell Atlantic at the time of termination to Bell Atlantic
     or another vendor designated by Bell Atlantic.

     21.7 Notwithstanding any termination hereof, the Parties shall continue to
   comply with their obligations under the Act to provide interconnection in
   accordance with Applicable Law.



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                                       17
<PAGE>

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Section 22. Confidentiality

    22.1 For the purposes of this Section 22, "Confidential Information" means
    the following information disclosed by one Party ("Discloser") to the other
    Party ("Recipient") in connection with this Agreement:

        22.1.1 All information disclosed by either Party to the other pursuant
        to Attachments I-X of this Agreement arising from the performance of
        this Agreement, including, but not limited to, books, records, documents
        and other information disclosed in an audit performed pursuant to this
        Agreement; and

        22.1.2 Such other information as is identified as Confidential
        Information in accordance with Section 22.2.

     22.2 All information which is to be treated as Confidential Information
     under Section 22.1.2 shall:

         22.2.1 If in written, graphic, electromagnetic, or other tangible form,
         be marked as "Confidential Information"; and

         22.2.2 If oral, (i) be identified by the Discloser at the time of
         disclosure to be "Confidential Information", and (ii) be set forth in a
         written summary which identifies the information as "Confidential
         Information" and is delivered by the Discloser to the Recipient within
         ten (10) days after the oral disclosure.

         22.2.3 Each Party shall have the right to correct an inadvertent
         failure to identify such oral information as Confidential Information
         by giving written notification within thirty (30) days after the
         information is disclosed. The Recipient shall, from that time forward,
         treat such information as Confidential Information.

     22.3 In addition to any requirements imposed by law, including, but not
     limited to, 47 U.S.C. (S) 222, for a period of three (3) years from the
     receipt of Confidential Information from the Discloser, except as otherwise
     specified in this Agreement, the Recipient1 agrees:

         22.3.1 To use the Confidential Information only for the purpose of
         performing under this Agreement, including, to the extent applicable,
         the planning and operation of the Recipient's network; and

         22.3.2 To use the same degree of care that it uses with similar
         confidential information of its own, to hold the Confidential
         Information in confidence and to disclose it to no one other than
         the directors, officers and employees of the Recipient and the
         Recipient's Affiliates, having a need to know the Confidential
         Information for the purpose of performing under this Agreement.


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     22.4 A Recipient may disclose the Discloser's Confidential Information to a
     third party agent or consultant, provided that prior to such disclosure the
     agent or consultant has executed a written agreement of non-disclosure and
     non-use comparable in scope to the terms of this Section 22.

     22.5 The Recipient may make copies of Confidential Information only as
     reasonably necessary to perform its obligations and exercise its rights
     under this Agreement. All such copies shall bear the same copyright and
     proprietary rights notices as are contained on the original.

     22.6 The Recipient shall return all Confidential Information defined in
     Section 22.1.2 in the format in which it was received from the Discloser,
     including any copies made by the Recipient, within thirty (30) days after a
     written request is delivered to the Recipient, and/or destroy all such
     Confidential Information, except for Confidential Information that the
     Recipient reasonably requires to perform its obligations under this
     Agreement. If the Recipient loses or makes an unauthorized disclosure of
     the Discloser's Confidential Information, it shall notify the Discloser
     immediately and use reasonable efforts to retrieve the lost or improperly
     disclosed information.

     22.7 The requirements of this Section 22 shall not apply to Confidential
     Information:

          22.7.1 Which was in the possession of the Recipient free of
          restriction prior to its receipt from the Discloser;

          22.7.2 After it becomes publicly known or available through no breach
          of this Agreement by the Recipient, the Recipient's Affiliates, or the
          directors, officers, employees, agents, or contractors, of the
          Recipient or the Recipient's Affiliates;

          22.7.3 After it is rightfully acquired by the Recipient free of
          restrictions on its disclosure;

          22.7.4 Which is independently developed by personnel of the Recipient;
          or

          22.7.5 To the extent the disclosure is required by law, or made to a
          court, or governmental agency for the purpose of enforcing its rights
          under this Agreement; provided the Discloser has been notified
          of an intended disclosure promptly after the Recipient becomes aware
          of a required disclosure or decides to make such a voluntary
          disclosure to enforce its rights, the Recipient undertakes reasonable,
          lawful measures to avoid disclosing the Confidential Information until
          the Discloser has had reasonable time to seek a protective order, and
          the Recipient complies with any protective order that covers the
          Confidential Information to be disclosed.



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    22.8 Each Party's obligations to safeguard Confidential Information
    disclosed prior to expiration, cancellation or termination of this Agreement
    shall survive such expiration, cancellation or termination.

    22.9 Confidential Information shall remain the property of the Discloser,
    and the Discloser shall retain all of the Discloser's right, title and
    interest in any Confidential Information disclosed by the Discloser to the
    Recipient. Except as otherwise expressly provided elsewhere in this
    Agreement, no license is granted by this Agreement with respect to any
    Confidential Information (including, but not limited to, under any patent,
    trademark, or copyright), nor is any such license to be implied, solely by
    virtue of the disclosure of any Confidential Information.

    22.10 Each Party agrees that the Discloser would be irreparably injured by a
    breach of this Section 22 by the Recipient, the Recipient's Affiliates, or
    the directors, officers, employees, agents or contractors of the Recipient
    or the Recipient's Affiliates, and that the Discloser shall be entitled to
    seek equitable relief, including injunctive relief and specific performance,
    in the event of any breach of the provisions of this Section 22. Such
    remedies shall not be deemed to be the exclusive remedies for a breach of
    this Section 22, but shall be in addition to any other remedies available at
    law or in equity.

    22.11 The provisions of this Section 22 shall be in addition to and shall
    not limit, alter, define or contradict any provisions of Applicable Law,
    including, but not limited to, 47 U.S.C. (S) 222, and are not intended to
    constitute a waiver by a Party of any right with regard to protection of the
    confidentiality of information (whether or not defined as "Confidential
    Information" for purposes of this Agreement) of the Party or its customers
    provided by Applicable Law.

    22.12 Without in any way limiting the foregoing provisions of Section 22,
    each Party shall comply with 47 U.S.C. (S) 222, any implementing rules,
    regulations, and orders thereunder, and other federal and state rules and
    regulations addressing Customer Proprietary Network Information ("CPNI") and
    Carrier Information. A Party shall not access (including, but not limited
    to, through electronic interfaces and gateways provided under this
    Agreement), use or disclose CPNI or other customer information unless the
    Party has obtained any customer authorization required by Applicable Law for
    such access, use and/or disclosure. By accessing, using or disclosing CPNI
    or other customer information, a Party represents and warrants that the
    Party has obtained any customer authorization required by Applicable Law
    for such access, use or disclosure. A Party accessing, using or disclosing
    CPNI or other customer information shall upon request by the other Party
    provide proof of any customer authorization for such access, use or
    disclosure, required by Applicable Law (including, copies of any written
    authorization). Without limiting the foregoing provisions of this Section
    22, where required by 47 U.S.C. (S) 222, or other provision of Applicable
    Law, a Party shall obtain a signed letter of authorization from the
    applicable end user in order to obtain CPNI or other customer information
    from the other Party.


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     22.13 Each Party ("Auditing Party") shall have the right to audit the other
     Party ("Audited Party"), to ascertain whether the Audited Party is
     complying with the requirements of Applicable Law and this Agreement with
     regard to the Audited Party's access to, and use and disclosure of, CPNI
     and other customer information, which is made available by the Auditing
     Party to the Audited Party under this Agreement. Any audit conducted under
     this Section 22.13 shall be conducted in accordance with Section 23,
     "Audits and Inspections". Any information disclosed by the Audited Party to
     the Auditing Party or the Auditing Party's employees, Agents or
     contractors, in an audit conducted under this Section 22.13 shall be
     considered to be Confidential Information under this Section 22.

     22.14 To the extent permitted by Applicable Law, each Party ("Auditing
     Party") shall have the right to monitor the access of the other Party
     ("Audited Party") to CPNI and other customer information which is made
     available by the Auditing Party to the Audited Party under this Agreement,
     to ascertain whether the Audited Party is complying with the requirements
     of Applicable Law and this Agreement with regard to the Audited Party's
     access to, and use and disclosure of, such CPNI and other customer
     information. To the extent permitted by Applicable Law, the foregoing right
     shall include, but not be limited to, the right to electronically monitor
     the Audited Party's access to and use of CPNI and other customer
     information which is made available by the Auditing Party to the Audited
     Party under this Agreement through electronic interfaces or gateways, to
     ascertain whether the Audited Party is complying with the requirements of
     Applicable Law and this Agreement with regard to the Audited Party's access
     to, and use and disclosure of, such CPNI and other customer information.

      22.15 Nothing herein shall be construed as limiting the rights of either
      Party with respect to its own subscriber information under any Applicable
      Law, including without limitation Section 222 of the Act.

Section 23. Audits and Examinations

      23.1 As applicable consistent with the provision of the relevant services
      or functions by a Party under this Agreement, each Party may audit the
      other Party's books, records and documents for the purpose of evaluating
      the accuracy of the other Party's bills and performance reports rendered
      under this Agreement. Such audits may be performed no more than a total
      of four (4) times in a calendar year nor more often than once every nine
      (9) months for a specific subject matter area; provided, that particular
      subject matter audits may be conducted more frequently (but no more
      frequently than once in each calendar quarter) if the immediately prior
      audit for such area found previously uncorrected net inaccuracies or
      errors in billing or performance reporting in favor of the audited Party
      having an aggregate value of at least five percent (5%) of the amounts
      payable by the auditing Party, or statistics reportable by the audited
      Party, relating to services provided by the audited Party during the
      period covered by the audit.



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July 8, 1997                                                              PART A


     23.2 In addition to the audits described in Section 23.1, each Party may
     audit the other Party's books, records and documents for the purpose of
     evaluating compliance with CPNI where the audited Party has access to CPNI
     in the custody of the auditing Party pursuant to this Agreement. Such CPNI
     audits must be performed in a minimally disruptive fashion, and an audited
     Party may bring objections to the Commission, if the audits are
     unnecessarily intrusive and the Parties cannot resolve their disputes. Such
     CPNI audits may not be performed more frequently than annually; provided,
     however, that the frequency of CPNI audits may be increased to quarterly if
     violations of a Party's CPNI obligations exceeds five percent (5%)of the
     audit sample.

     23.3 The auditing Party may employ other persons or firms for this purpose.
     Such audit shall take place at a time and place agreed on by the Parties;
     provided, that the auditing Party may require that the audit commence no
     later than sixty (60) days after the auditing Party has given notice of the
     audit to the other Party.

     23.4 The audited Party shall promptly correct any error that is revealed in
     a billing audit, including back-billing of any underpayments and making a
     refund, in the form of a billing credit, of any over-payments. Such back-
     billing and refund shall appear on the audited Party's bill no later than
     the bill for the third full billing cycle after the Parties have agreed
     upon the accuracy of the audit results.

     23.5 Each Party shall cooperate fully in any audits required hereunder,
     providing reasonable access to any and all employees, books, records and
     documents, reasonably necessary to assess the accuracy of the audited
     Party's bills or performance reports, or compliance with CPNI obligations,
     as appropriate.

     23.6 Audits shall be performed at the auditing Party's expense, provided
     that there shall be no charge for reasonable access to the audited Party's
     employees, books, records and documents necessary to conduct the audits
     provided for hereunder.

     23.7 Books, records, documents, and other information, disclosed by the
     audited party to the auditing Party or the Auditing Party's employees,
     agents or contractors in an audit under this Section 23, shall be deemed
     to be Confidential Information under Section 22.

     23.8 This Section 23 shall survive expiration or termination of this
     Agreement for a period of two (2) years after expiration or termination of
     this Agreement.

Section 24. Dispute Resolution Procedures

     24.1 In the event the Commission retains continuing jurisdiction to
     implement and enforce the terms and conditions of this Agreement, the
     Parties agree that any dispute arising out of or relating to this Agreement
     that the Parties themselves cannot resolve, may be submitted to the
     Commission for resolution. The Parties agree to seek expedited resolution
     by the Commission, pursuant to applicable procedures established by the
     Commission. During the Commission proceeding, each Party shall continue to
     perform


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     its obligations under this Agreement; provided, however that neither Party
     shall be required to act in any unlawful fashion. This provision shall not
     preclude the Parties from seeking relief available in any other forum.

     24.2 The Parties acknowledge that the terms of this Agreement were
     established pursuant to an order of the Commission. Any and all of the
     terms of this Agreement may be altered or abrogated by a successful
     challenge to the Agreement (or to the order approving the Agreement) as
     permitted by Applicable Law. By signing this Agreement, the Parties do not
     waive the right to pursue such a challenge.

Section 25. Bona Fide Request Process for Further Unbundling

     25.1 The Parties recognize that, because MCIm plans to maintain a
     technologically advanced network, it is likely to seek further unbundling
     of Network Elements or the introduction of new Network Elements.
     Accordingly, MCIm may request such new unbundled Network Elements or
     arrangements from time to time by submitting a request in writing ("Bona
     Fide Request" or "BFR"). Bell Atlantic shall promptly consider and analyze
     MCIm's submission of a Bona Fide Request that Bell Atlantic provide: (a) a
     method of Interconnection or access to a Network Element not otherwise
     provided under this Agreement at the time of such Bona Fide Request; (b) a
     method of Interconnection or access to a Network Element that is different
     in quality to that which Bell Atlantic provides to itself, its Affiliates,
     or its subscribers at the time of such request; (c) Collocation at a
     location other than a Bell Atlantic Central Office; and (d)such other
     arrangement, service, or Network Element for which a Bona Fide Request is
     required under this Agreement. Items (a) through (d) above may be referred
     to individually as a "BFR Item." The Bona Fide Request process set forth
     herein does not apply to those services requested pursuant to Report &
     Order and Notice of Proposed Rulemaking 91-141 (rel. October 19, 1992),
     Paragraph 259 and Footnote 603 or subsequent orders.

     25.2 A Bona Fide Request shall be submitted in writing and shall contain
     information required to perform a preliminary analysis of the requested BFR
     Item. Such information will include a technical description of each BFR
     Item and reasonable estimates of the number or volume requested, the
     location(s)of each BFR Item, and the date(s) each BFR Item is desired. MCIm
     shall submit each BFR via United States Postal Service or private courier,
     return receipt requested.

     25.3 MCIm may cancel a Bona Fide Request at any time, but shall pay Bell
     Atlantic's reasonable and demonstrable costs of processing and/or
     implementing the Bona Fide Request up to the date of cancellation;
     except MCIm shall not be charged for preliminary analysis if costs do not
     exceed one hundred dollars ($100). Bell Atlantic shall notify MCIm if
     costs will exceed five thousand dollars ($5,000). Bell Atlantic shall
     provide MCIm with weekly status reports on the progress of its analysis and
     shall include the cost of such status reports in the costs of processing
     the BFR.

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     25.4 Within fifteen (15) business days after its receipt of a Bona Fide
     Request, Bell Atlantic shall provide to MCIm a preliminary analysis of the
     BFR Item. The preliminary analysis shall respond in one of the following
     ways:

           25.4.1 confirm that Bell Atlantic will offer the BFR Item and
           identify the date (no more than ninety (90) days after the date of
           the preliminary analysis) when Bell Atlantic will deliver a firm
           price proposal, including service description, pricing and an
           estimated schedule for availability ("Bona Fide Request Price
           Proposal");

           25.4.2 provide a detailed explanation that such BFR Item is not
           technically feasible and/or that the BFR Item does not qualify as one
           that is required to be provided under the Act;

           25.4.3 inform MCIm that Bell Atlantic must do laboratory testing to
           determine whether the BFR Item is technically feasible;

           25.4.4 inform MCIm that Bell Atlantic must do field testing to
           determine whether the BFR Item is technically feasible;

           25.4.5 inform MCIm that it is necessary for the Parties to undertake
           a joint technical/operational field test in order to determine both
           technical feasibility and operational cost impacts of the BFR Item;
           or

           25.4.6 request face-to-face meetings between technical
           representatives of both Parties to further explain the BFR Item. No
           later than five (5) business days following such meetings, Bell
           Atlantic will provide a preliminary analysis in one of the ways
           identified in Sections 25.4.1 through 25.4.5. Both Parties shall make
           reasonable efforts to schedule such meetings as expeditiously as
           possible.

     25.5 Within ten (10) business days after receiving Bell Atlantic's
     preliminary analysis from Section 25.4.3, 25.4.4, or 25.4.5, MCIm shall:

           25.5.1 in the case of Sections 25.4.3 or 25.4.4, (i) negotiate a
           mutually agreeable, reasonably expeditious schedule for Bell
           Atlantic's testing, (ii) a mutually agreeable date (no more than
           ninety (90) days after the testing has shown the BFR Item is
           technically feasible) when Bell Atlantic will deliver a Bona Fide
           Request Price Proposal, and (iii) a mutually agreeable arrangement
           for sharing the testing costs; or

           25.5.2 in the case of Section 25.4.5, (i) negotiate a mutually
           agreeable, reasonably expeditious schedule for joint
           technical/operational field testing, (ii) a mutually agreeable date
           (no more than 90 days after the testing has shown the BFR Item is
           technically feasible) when Bell Atlantic will deliver a Bona Fide
           Request Price Proposal, and a mutually agreeable arrangement for
           sharing the testing costs.


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July 8, 1997                                                            PART A


     25.6 In handling a Bona Fide Request pursuant to Section 25.4, Bell
     Atlantic shall, to the extent possible, utilize information from previously
     developed Bona Fide Requests in order to shorten its response times. MCIm
     may take advantage of previously canceled BFR work performed by Bell
     Atlantic on the same BFR Item or a substantially similar BFR Item, to the
     extent applicable.

     25.7 Within ten (10) business days after receiving Bell Atlantic's
     preliminary analysis from Section 25.4.1, MCIm shall:

          25.7.1 accept Bell Atlantic's date to deliver a Bona Fide Request
          Price Proposal;

          25.7.2 negotiate as expeditiously as possible a different date for
          Bell Atlantic to deliver a Bona Fide Request Price Proposal; or

          25.7.3 cancel the Bona Fide Request.

     25.8 Unless the Parties otherwise agree, a BFR Item shall be priced in
     accordance with Section 252(d)(1)of the Act and any applicable FCC or
     Commission rules, regulations, or orders. Consistent with Applicable Law,
     the price for each BFR Item shall include the reasonable and demonstrable
     costs incurred by Bell Atlantic in responding to the BFR, to the extent
     that Bell Atlantic has not previously been reimbursed for such costs.

     25.9 Within ninety (90) days after its receipt of the Bona Fide Request
     Price Proposal, MCIm must either place an order for such BFR Item pursuant
     to the Bona Fide Request Price Proposal or, if it believes such Bona Fide
     Request Price Proposal is inconsistent with the requirements of the Act,
     seek arbitration by the Commission, including the use of any available
     expedited procedures. If, within ninety (90)days after its receipt of the
     Bona Fide Request Price Proposal, MCIm fails to confirm an order for such
     BFR Item or seek arbitration by the Commission, Bell Atlantic may treat
     the Bona Fide Request as canceled by MCIm. If within ninety (90) days after
     issuance of a Commission order finding that a Bona Fide Request Price
     Proposal is consistent with the requirements of the Act, MCIm fails to
     place an order for such BFR Item, Bell Atlantic may treat the Bona Fide
     Request as canceled by MCIm.

     25.10 If a Party to a Bona Fide Request believes that the other Party is
     not requesting, or negotiating, or processing the Bona Fide Request in
     good faith, or disputes a determination, or price or cost quote, or is
     failing to act in accordance with Section 251 of the Act, such Party may
     seek mediation or arbitration by the Commission, including the use of any
     available expedited procedures, after giving the other Party written notice
     at least ten (10) days in advance.

Section 26. Branding

     26.1 In all cases in which a Party has control over handling of services
     provided to customers of the other Party using services procured under this
     Agreement, the Party so


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July 8, 1997                                                             PART A


   handling such services shall brand them at the points of subscriber contact
   as set forth in Attachment VIII.

   26.2 When Bell Atlantic technicians (including Bell Atlantic contractor
   technicians) have contact with a customer during a premise visit on behalf of
   MCIm, the Bell Atlantic technicians shall identify themselves as Bell
   Atlantic employees (or Bell Atlantic contractor employees) performing
   services on behalf of MCIm. When a Bell Atlantic technician leaves a status
   card during a premise visit on behalf of MCIm, the card will be a standard
   card used for other local service providers'customers, will be in
   substantially the form set forth in Exhibit A of this Part A, and will
   include the name and telephone number of each local service provider that
   elects to be listed on the card and agrees to compensate Bell Atlantic for
   that provider's share of Bell Atlantic's cost of printing and distributing
   the card. The Bell Atlantic technicians shall not leave any promotional or
   marketing literature for or otherwise market Bell Atlantic Telecommunications
   Services to the MCIm customer during a premise visit on behalf of MCIm, but
   may provide a telephone number for Bell Atlantic's customer service or sales
   department, in response to customer query about Bell Atlantic services.

   26.3 This Section 26 shall not confer on either Party any rights to the
   service marks, trademarks and trade names owned by or used in connection with
   services by the either Party or its Affiliates, except as expressly permitted
   by this Section 26.

Section 27. Taxes

   27.1 With respect to any purchase of services under this Agreement, if any
   Federal, state or local government tax, fee, duty, surcharge (including, but
   not limited to, any 911, telecommunications relay service, or universal
   service fund surcharge), or other tax-like charge (a "Tax") is required or
   permitted by Applicable Law to be collected from a Purchasing Party by the
   Providing Party, then: (i) the Providing Party shall bill the Purchasing
   Party for such Tax; (ii) the Purchasing Party shall timely remit such Tax to
   the Providing Party; and (iii) the Providing Party shall remit such collected
   Tax to the applicable taxing authority.

   27.2 With respect to any purchase of services under this Agreement, if any
   Tax is imposed by Applicable Law on the receipts of the Providing Party,
   which Applicable Law permits the Providing Party to exclude certain receipts
   received from sales of services for resale by the Purchasing Party, such
   exclusion being based solely on the fact that the Purchasing Party is also
   subject to a tax based upon receipts ("Receipts Tax"), then the Purchasing
   Party (i) shall provide the Providing Party with notice in writing in
   accordance with Section 27.7 of its intent to pay the Receipts Tax, and (ii)
   shall timely pay the Receipts Tax to the applicable taxing authority.

   27.3 With respect to any purchase of services under this Agreement, that are
   resold by the Purchasing Party to a subscriber of the Purchasing Party, if
   any Tax is imposed by Applicable Law on the subscriber of the Purchasing
   Party in connection with its purchase


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     of the resold Offered Services which the Purchasing Party is required to
     impose and/or collect from the subscriber, then the Purchasing Party
     (i) shall impose and/or collect such Tax from the subscriber, and (ii)shall
     timely remit such Tax to the applicable taxing authority.

          27.3.1 If the Providing Party has not received an exemption
          certificate from the Purchasing Party and fails to collect any Tax as
          required by Section 27.1, then, as between the Providing Party and the
          Purchasing Party, (i) the Purchasing Party shall remain liable for
          such uncollected Tax, and (ii) the Providing Party shall be liable for
          any interest and/or penalty assessed on the uncollected Tax by the
          applicable taxing authority.

          27.3.2 If the Providing Party properly bills the Purchasing Party for
          any Tax but the Purchasing Party fails to remit the Tax to the
          Providing Party as required by Section 27.1, then, as between the
          Providing Party and the Purchasing Party, the Purchasing Party shall
          be liable for such uncollected Tax and any interest and/or penalty
          assessed on the uncollected Tax by the applicable taxing authority.
          The Providing Party shall give timely notice to the Purchasing Party
          if any proposed assessment of Taxes, interest or penalties by the
          applicable taxing authority so as to afford the Purchasing Party an
          opportunity to cure any defect or inadequacy with its exemption
          certificate before assessment of any additional Taxes, interest or
          penalties is made by the taxing authority.

          27.3.3 If the Providing Party does not collect a Tax because the
          Purchasing Party has provided the Providing Party with an exemption
          certificate which is later found to be inadequate by the applicable
          taxing authority, then, as between the Providing Party and the
          Purchasing Party, the Purchasing Party shall be liable for such
          uncollected Tax and any interest and/or penalty assessed on the
          uncollected Tax by the applicable taxing authority.

          27.3.4 Except as provided in Section 27.3.5, if the Purchasing Party
          fails to pay the Receipts Tax as required by Section 27.2, then, as
          between the Providing Party and the Purchasing Party, (i) the
          Providing Party shall be liable for any Tax imposed on the Providing
          Party's receipts, and (b) the Purchasing Party shall be liable for any
          Tax imposed on the Purchasing Party's receipts and any interest and/or
          penalty assessed by the applicable taxing authority on either the
          Purchasing Party or the Providing Party with respect to the Tax on the
          Providing Party's receipts.

          27.3.5 If any discount or portion of a discount in price provided to
          the Purchasing Party under this Agreement (including, but not limited
          to, the discount provided for in Attachment I) represents Tax savings
          to the Providing Party which it was assumed the Providing Party would
          receive, because it was anticipated that receipts from sales of
          services (that would otherwise be subject to a Tax on such receipts)
          could be excluded from such Tax under Applicable Law, because the


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<PAGE>

July 8, 1997                                                            PART A


         services would be sold to a Telecommunications Services provider, and
         the Providing Party is, in fact, required by Applicable Law to pay such
         Tax on receipts from sales of services to the Purchasing Party, then,
         as between the Providing Party and the Purchasing Party, the Purchasing
         Party shall be liable for any such Tax and any interest and/or penalty
         assessed by the applicable taxing authority on either the Purchasing
         Party or the Providing Party with respect to the Tax on the Providing
         Party's receipts.

         27.3.6 With respect to any Tax imposed on subscribers of the Purchasing
         Party that the Purchasing Party is required to collect, as between the
         Providing Party and the Purchasing Party, the Purchasing Party shall
         remain liable for such Tax and any interest and/or penalty assessed on
         such Tax by the applicable taxing authority.

    27.4 If either Party is audited by a taxing authority, the other Party
    agrees to reasonably cooperate with the Party being audited in order to
    respond to any audit inquiries in a proper and timely manner so that the
    audit and/or any resulting controversy may be resolved expeditiously.

    27.5 If Applicable Law clearly exempts a purchase of services under this
    Agreement from a Tax, and if such Applicable Law also provides an exemption
    procedure, such as an exemption certificate requirement, then, if the
    Purchasing Party complies with such procedure, the Providing Party shall not
    collect such Tax during the effective period of the exemption. Such
    exemption shall be effective upon receipt of the exemption certificate or
    affidavit in accordance with Section 27.7.

    27.6 If Applicable Law appears to exempt a purchase of services under this
    Agreement from a Tax, but does not also provide an exemption procedure, then
    the Providing Party shall not collect such Tax if the Purchasing Party
    (i) furnishes the Providing Party with a letter signed by an officer of the
    Purchasing Party requesting an exemption and citing the provision in the
    Applicable Law which appears to allow such exemption, and (ii) supplies the
    Providing Party with an indemnification agreement, reasonably acceptable to
    the Providing Party, which holds the Providing Party harmless on an after-
    tax basis with respect to forbearing to collect such Tax.

    27.7 All notices, affidavits, exemption certificates or other communications
    required or permitted to be given by either Party to the other under this
    Section 27, shall be made in writing and shall be delivered personally or
    sent by prepaid overnight express service, and sent to the addresses stated
    in Section 14 and to the following:

          To Bell Atlantic:  Tax Administration
                             Bell Atlantic Network Services, Inc.
                             1717 Arch Street, 30th Floor
                             Philadelphia, PA 19103



MCIm-BELL ATLANTIC INTERCONNECTION AGREEMENT - PENNSYLVANIA            PART A-28
<PAGE>

July 8, 1997                                                            PART A


          To MCIm:       MCI Carrier Group
                         MCI Telecommunications Corporation
                         1133 19th Street, NW
                         Washington, DC 20036

     Either Party may from time-to-time designate another address or addressee
     by giving notice in accordance with the terms of this Section 27.7. Any
     notice or other communication shall be deemed to be given when received.

Section 28. Responsibility for Environmental Contamination

     28.1 MCIm shall in no event be liable to Bell Atlantic for any costs
     whatsoever resulting from a violation of a federal, state or local
     environmental law by Bell Atlantic, its contractors or agents arising out
     of this Agreement (a "Bell Atlantic Environmental Violation"). Bell
     Atlantic shall, at MCIm's request, indemnify, defend, and hold harmless
     MCIm, each of its officers, directors and employees from and against any
     losses, damages, claims, demands, suits, liabilities, fines, penalties and
     expenses (including reasonable attorneys fees) that are caused by a Bell
     Atlantic Environmental Violation.

     28.2 Bell Atlantic shall in no event be liable to MCIm for any costs
     whatsoever resulting from a violation of a federal, state or local
     environmental law by MCIm, its contractors or agents arising out of this
     Agreement (an "MCIm Environmental Violation"). MCIm shall, at Bell
     Atlantic's request, indemnify, defend, and hold harmless Bell Atlantic,
     each of its officers, directors and employees from and against any losses,
     damages, claims, demands, suits, liabilities, fines, penalties and expenses
     (including reasonable attorneys fees)that are caused by an MCIm
     Environmental Violation.

     28.3 In the event any suspect materials within Bell Atlantic-owned,
     operated or leased facilities are identified to be asbestos-containing,
     MCIm will ensure that to the extent any activities which it undertakes in
     the facility disturb such suspect materials, such MCIm activities will be
     in accordance with applicable local, state and federal environmental and
     health and safety statutes and regulations. Except for abatement activities
     undertaken by MCIm or equipment placement activities that result in the
     generation or placement of asbestos containing material, MCIm shall not
     have any responsibility for managing, nor be the owner of, not have any
     liability for, or in connection with, any asbestos containing material at
     Bell Atlantic-owned, operated or leased facilities. Bell Atlantic agrees to
     immediately notify MCIm if Bell Atlantic undertakes any asbestos control or
     asbestos abatement activities that potentially could affect MCIm equipment
     or operations, including, but not limited to, contamination of equipment.

Section 29. Facilities

     29.1 A providing Party or its suppliers shall retain all right, title and
     interest in, and ownership of, all facilities, equipment, software, and
     wiring, used to provide the


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July 8, 1997                                                             PART A


     providing Party's services. During the period in which services are
     provided, the providing Party shall have access at all reasonable times to
     the purchasing Party's and the purchasing Party's customers' locations for
     the purpose of installing, maintaining, repairing, and inspecting all
     facilities, equipment, software, and wiring, used to provide the services.
     At the conclusion of the period in which services are provided, the
     providing Party shall have access at the purchasing Party's and the
     purchasing Party's customers' locations at all reasonable times to remove
     all facilities, equipment, software, and wiring used to provide the
     services. The purchasing Party shall, at the purchasing Party's expense,
     obtain any rights and authorizations necessary for such access.

     29.2 Except as otherwise stated in this Agreement or agreed to in writing
     by a providing Party, a providing Party shall not be responsible for the
     installation, maintenance, repair or inspection, of facilities, equipment,
     software, or wiring furnished by the purchasing Party or the purchasing
     Party's customers for use with the providing Party's services.

Section 30. Option to Obtain Services Under Other Agreements

     30.1 In accordance with the requirements of 47 U.S.C. (S) 252(i), each
     Party shall, upon written request by the other Party, make available to the
     requesting Party any interconnection, service, or network element provided
     under an agreement with a third party, and which is approved by the
     Commission pursuant to 47 U.S.C. (S) 252, upon the same terms and
     conditions (including prices) provided in the agreement with the third
     party. This Agreement shall thereafter be amended to incorporate the terms
     and conditions (including prices) from the third party agreement applicable
     to the interconnection, service, or network element that the requesting
     Party has elected to purchase pursuant to the terms and conditions of the
     third party agreement. The amended rates, terms and conditions from the
     third party agreement shall be effective upon: (i) amendment by the
     Parties, or (ii) sixty (60) days after the date of written request,
     whichever is earlier.

     30.2 To the extent the exercise of the foregoing option requires a
     rearrangement of facilities by the providing Party, the requesting Party
     shall be liable for the non-recurring charges associated therewith, as well
     as for any termination charges, if any, associated with the termination of
     existing facilities or services.

Section 31. Other Services

     31.1 This Agreement applies only to "services" as defined in this
     Agreement. To the extent that services subscribed to under this Agreement
     by a purchasing Party are interconnected to or used with other services,
     facilities, equipment, software, or wiring, provided by the providing Party
     or by other persons, such other services, facilities, equipment, software,
     or wiring, shall not be construed to be provided under this Agreement. Any
     providing Party services, facilities, equipment, software, or wiring, to be
     used by the purchasing Party which are not subscribed to by the purchasing
     Party



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July 8, 1997                                                            PART A


under this Agreement must be subscribed to by the purchasing Party separately,
pursuant to other written agreements (including, but not limited to, applicable
providing Party Tariffs).

     31.2 Without in any way limiting Section 31.1, the Parties agree that this
     Agreement does not apply to the following Bell Atlantic services and
     products: Bell Atlantic Answer Call, Bell Atlantic Answer Call Plus, Bell
     Atlantic Basic Mailbox, Bell Atlantic Voice Mail, and other Bell Atlantic
     voice mail and voice messaging services; Bell Atlantic Optional Wire
     Maintenance Plan, Bell Atlantic Guardian Enhanced Maintenance Service, Bell
     Atlantic Sentry I Enhanced Maintenance Service, Bell Atlantic Sentry II
     Enhanced Maintenance Service, Bell Atlantic Sentry III Enhanced Maintenance
     Service, and other inside wire maintenance services; customer premises
     equipment; Telephone Directory advertisements (except as stated in
     Attachment VIII); and any service that incorporates the payphone station
     equipment.

     31.3 Without in any way limiting Section 31.1 or Section 31.2, the
     Parties also agree that this Agreement does not apply to the installation,
     maintenance, repair, inspection, or use of any facilities, equipment,
     software, or wiring, located on the purchasing Party's side of the Network
     Rate Demarcation Point applicable to the purchasing Party and does not
     grant to the purchasing Party a right to installation, maintenance, repair,
     inspection, or use, of any such facilities, equipment, software, or wiring.
     Installation, maintenance, repair, inspection, or use of facilities,
     equipment, software, or wiring, located on the purchasing Party's side of
     the Network Rate Demarcation Point applicable to the purchasing Party must
     be contracted for by the purchasing Party separately, pursuant to other
     written agreements, at rates stated in such other written agreements.

Section 32. Provision and Use of Services

     32.1 A Party may fulfill its obligations under this Agreement itself or may
     cause an Affiliate of the Party to take the action necessary to fulfill the
     Party's obligations; provided that a Party's use of an Affiliate to perform
     this Agreement shall not release the Party from any liability or duty to
     fulfill its obligations under this Agreement.

     32.2 Except as otherwise expressly stated in this Agreement, each Party, at
     its own expense, shall be responsible for obtaining from governmental
     authorities, property owners, other Telecommunications Carriers, and any
     other persons or entities, all rights and privileges (including, but not
     limited to, Rights of Way, space and power), which are necessary for the
     Party to provide its services pursuant to this Agreement.

     32.3 Except as otherwise provided in this Agreement, this Agreement does
     not prevent a purchasing Party from using the services provided by a
     providing Party pursuant to this Agreement in connection with other
     technically compatible services provided by the providing Party pursuant to
     this Agreement or with any services provided by the purchasing Party or a
     third party, provided, however, that unless otherwise provided herein,
     interconnection services, call transport and termination services, and
     unbundled


  MCIm-BELL ATLANTIC INTERCONNECTION AGREEMENT -  PENNSYLVANIA        PART A-31
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July 8, 1997                                                          PART A


 Network Elements shall be available under the terms and conditions (including
 prices) set forth in this Agreement and shall be used by the purchasing Party
 solely for purposes consistent with obligations set forth in the Act and any
 rules, regulations or orders thereunder.

Section 33. Selection of IntraLATA Telecommunications Service Provider

     33.1 The Parties agree to apply the principles and procedures set forth in
     Sections 64.1100 and 64.1150 of the FCC Rules, 47 C.F.R. (S)(S) 64.1100 and
     64.1150, to the process for end user selection of an IntraLATA
     Telecommunications Service provider; provided that if the FCC or the
     Commission adopts rules governing the process for end user selection of an
     IntraLATA Telecommunications Service provider, the Parties shall apply such
     rules rather than the principles and procedures set forth in (S)(S) 64.1100
     and 64.1150.

     33.2 In the event a Party ("Requesting Party")which requests the other
     Party to change an end user's Telecommunications Service (including, but
     not limited to, an end user's selection of an IntraLATA Telecommunications
     Service provider): (a) fails to provide documentary evidence of the end
     user's IntraLATA Telecommunications Service provider selection upon
     request; or (b) requests changes in the end user's Telecommunications
     Service without having obtained authorization for such change from the end
     user pursuant to the principles and procedures set forth in Sections
     64.1100 and 64.1150 or other applicable FCC or Commission rules, the
     Requesting Party shall indemnify, defend and hold harmless the other Party
     for any resulting Claims. In addition, the Requesting Party shall be liable
     to the other Party for all charges that would be applicable to the end user
     for the initial change in the end user's Telecommunications Service and any
     charges for restoring the end user's Telecommunications Service to its end
     user authorized condition, including to the appropriate IntraLATA
     Telecommunications Service provider.

     33.3 A Providing Party shall not require the Purchasing Party to produce a
     letter of authorization, disconnect order, or other writing, from the
     Purchasing Party's subscriber as a pre-condition to processing an Order
     from the Purchasing Party.

Section 34. Service Standards

     34.1 Bell Atlantic shall provide service to MCIm at a level of performance
     that Bell Atlantic is required by Applicable Law (including 47 U.S.C. (S)
     251)to meet in providing service to MCIm.

     34.2 Bell Atlantic shall offer premium service (services provided at a
     higher level than that required by Section 34.1) to MCIm, if MCIm requests
     premium service in accordance with Section 25 and MCIm compensates Bell
     Atlantic for the incremental cost of providing such premium service.



MCIm-BELL ATLANTIC INTERCONNECTION AGREEMENT - PENNSYLVANIA          PART A-32
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July 8, 1997                                                             PART A


     34.3 Upon MCIm's request, Bell Atlantic shall provide to MCIm reports on
     all material measures of service Parity. MCIm may request a report on all
     measures that are reasonably related to establishing the Parity level and
     whether MCIm is receiving services at Parity. Such reports shall indicate
     for each material measure the service and performance level provided by
     Bell Atlantic to itself, its Affiliates, MCIm, and other CLECs. The reports
     required by this Section 34 are identified in Attachment X of this
     Agreement.

     34.4 To the extent Bell Atlantic through its Tariffs provides credits for
     substandard performance, Bell Atlantic shall provide MCIm such credits for
     substandard performance of services provided under this Agreement.

     34.5 Pursuant to Section 23 of this Part A, MCIm shall have the right, at
     its expense, to conduct reasonable audits or other verifications of
     information and reports provided by Bell Atlantic under this Section 34.

Section 35. Subcontracting

     35.1 If any obligation under this Agreement is performed through a
     subcontractor, the subcontracting Party shall remain fully responsible for
     the performance of this Agreement in accordance with its terms, including
     any obligations it performs through the subcontractor. The subcontracting
     Party shall be solely responsible for payments due its subcontractors. No
     subcontractor shall be deemed a third party beneficiary for any purposes
     under this Agreement.

Section 36. Amendments and Modifications

     36.1 No provision of this Agreement shall be deemed waived, amended or
     modified by either Party unless such a waiver, amendment or modification is
     in writing, dated, and signed by both Parties.

Section 37. Severability

     37.1 If any term, condition or provision of this Agreement is held to be
     invalid or unenforceable for any reason, such invalidity or
     unenforceability shall not invalidate the entire Agreement (unless such
     construction would be unreasonable), and the Agreement shall be construed
     as if it did not contain the invalid or unenforceable provision or
     provisions, and the rights and obligations of each Party construed and
     enforced accordingly.



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<PAGE>

July 8, 1997                                                            PART A


Section 38. Headings Not Controlling

     38.1 The headings of Articles and Sections of this Agreement are for
     convenience of reference only, and shall in no way define, modify or
     restrict the meaning or interpretation of the terms or provisions of this
     Agreement.

Section 39. Entire Agreement

     39.1 This Agreement constitutes the entire agreement between the Parties on
     the subject matter hereof, and supersedes any prior or contemporaneous
     agreement, understanding, or representation on the subject matter hereof.
     Except as otherwise provided in this Agreement, the terms in this Agreement
     may not be waived or modified except by a written document which is signed
     by the Parties.

Section 40. Counterparts

     40.1 This Agreement may be executed in any number of counterparts, each of
     which shall be deemed an original; but such counterparts shall together
     constitute one and the same instrument.

Section 41. Successors and Assigns

     41.1 This Agreement shall be binding upon, and inure to the benefit of,
     the Parties hereto and their respective successors and permitted assigns.

Section 42. Good Faith Performance

     42.1 In the performance of their obligations under this Agreement, the
     Parties shall cooperate fully and act in good faith and consistently with
     the intent of the Act. Where notice, approval or similar action by a Party
     is permitted or required by any provision of this Agreement (including,
     without limitation, the obligation of the Parties to further negotiate the
     resolution of new or open issues under this Agreement), such action shall
     not be unreasonably delayed, withheld or conditioned.

Section 43. Joint Work Product

     43.1 This Agreement is the joint work product of the representatives of the
     Parties. For convenience, this Agreement has been drafted in final form by
     one of the Parties. Accordingly, in the event of ambiguities, no inferences
     shall be drawn against either Party solely on the basis of authorship of
     this Agreement.


MCIm-BELL ATLANTIC INTERCONNECTION AGREEMENT - PENNSYLVANIA           PART A-34
<PAGE>

July 8, 1997                                                           PART A

      IN WITNESS WHEREOF, each of the Parties has caused this Agreement to be
executed by its duly authorized representatives.

MCImetro Access Transmission               Bell Atlantic  Pennsylvania, Inc.
Services, Inc.


By: /s/ Dennis J. Kerr                     By:
   --------------------------                 -----------------------------

Name: Dennis J. Kerr                       Name:
     ------------------------                   ---------------------------

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

Date: 7/7/97                                Date:
     ------------------------                    --------------------------



MCIm-BELL ATLANTIC INTERCONNECTION AGREEMENT - PENNSYLVANIA        PART A-35
<PAGE>

July 8, 1997                                                           PART A

     IN WITNESS WHEREOF, each of the Parties has caused this Agreement to be
executed by its duly authorized representatives.


MCImetro Access Transmission                Bell Atlantic-Pennsylvania, Inc.
Services, Inc.
                                                Daniel J. Whelan
By:___________________________              By:_____________________________

Name:                                       Name: Daniel J. Whelan
     _________________________                   ___________________________

Title:                                      Title: President and CEO
      ________________________                    __________________________

Date:                                       Date: 7/8/97
     _________________________                   ___________________________


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<PAGE>

July 8, 1997                                                    ATTACHMENT II


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

                                 Attachment II
                                 LOCAL RESALE

      Section 1. Telecommunications Services Provided for Resale        II-1
      Section 2. General Terms and Conditions for Resale                II-1
      Section 3. Service Functions                                      II-4




MCIm-BELL ATLANTIC INTERCONNECTION AGREEMENT - PENNSYLVANIA              II-i
<PAGE>

July 8, 1997                                                    ATTACHMENT II


                                 ATTACHMENT II

                                 LOCAL RESALE

Section 1. Telecommunications Services Provided for Resale

  1.1 In accordance with and subject to the requirements of Applicable Law, Bell
  Atlantic shall make available to MCIm for resale any Telecommunications
  Service that Bell Atlantic currently provides or may offer hereafter,
  including the service functions described in Section 3 below. Such
  Telecommunications Services and service functions are collectively referred to
  as "Local Resale."

  1.2 To the extent that this Attachment describes services which Bell Atlantic
  shall make available to MCIm for resale pursuant to this Agreement, this list
  of services is neither all inclusive nor exclusive. All Telecommunications
  Services which are to be offered for resale are subject to the terms herein.

  1.3 Bell Atlantic shall make all of its Telecommunications Services available
  for resale to MCIm on terms and conditions that are reasonable and Non-
  Discriminatory.

  1.4 Bell Atlantic will provide services to MCIm for resale that are equal in
  quality, subject to the same conditions, and provided within the same
  provisioning time intervals that Bell Atlantic provides itself, including end
  users. To the extent applicable, Bell Atlantic shall also conform to the
  specific requirements of Attachment VIII.

  1.5 The specific business process requirements and systems interface
  requirements are set forth in Attachment VIII.

  1.6 Notwithstanding any other provision of this Attachment II, Bell Atlantic
  shall be entitled to change its Telecommunications Services offerings, subject
  to the notice provisions of Attachment VIII, Section 1.

  1.7 MCIm acknowledges that it has a duty under Section 25 l(b)(1)of the Act
  not to prohibit, and not to impose unreasonable and discriminatory conditions
  or limitations on the resale of its Telecommunications Services. MCIm will
  develop its services with the knowledge that when they are available, Bell
  Atlantic may request negotiations with MCIm for the resale of such services.
  MCIm will negotiate in good faith the terms and conditions necessary for Bell
  Atlantic to purchase such services for resale from MCIm.

  Section 2. General Terms and Conditions for Resale

   2.1 Pricing. The prices regarding Local Resale are set forth in Attachment I
   of this Agreement.

MCIm-BELL ATLANTIC INTERCONNECTION AGREEMENT - PENNSYLVANIA                 II-1
<PAGE>

July 8, 1997                                                      ATTACHMENT II


     2.2 Restrictions on Resale

         2.2.1 Local Resale services may be purchased by MCIm under this
         Agreement solely for the purpose of resale by MCIm. Local services to
         be purchased for other purposes (including, but not limited to, MCIm's
         own use) must be purchased pursuant to separate written agreements,
         including, but not limited to, applicable Tariffs of Bell Atlantic.
         MCIm may purchase Local Resale services under this Agreement for resale
         to its Affiliates if MCIm resells such services as a Telecommunications
         Carrier pursuant to terms and conditions that comply with all
         applicable Commission rules, including non-discrimination rules.

         2.2.2 MCIm shall not resell Bell Atlantic's residential Local Resale
         services to customers who are ineligible to subscribe to such Local
         Resale services from Bell Atlantic.

         2.2.3 MCIm shall not resell Lifeline or any other means-tested service
         offerings to customers not eligible to subscribe to such service
         offerings from Bell Atlantic.

         2.2.4 MCIm shall not resell grandfathered Local Resale services to
         customers who are ineligible to subscribe to such Local Resale services
         from Bell Atlantic.

         2.2.5 The Parties agree to negotiate the applicability of any category-
         to-category restriction on the resale of Bell Atlantic's Local Resale
         services that may be offered by Bell Atlantic in the future. If the
         Parties are unable to reach agreement, the Parties will submit the
         dispute to the Commission under the dispute resolution procedures of
         Part A, Section 24 (Dispute Resolution Procedures), and Bell Atlantic
         shall bear the burden of proving that the category-to-category
         restriction is reasonable and nondiscriminatory.

     2.3 Requirements for Specific Services

         2.3.1 CENTREX Requirements

               2.3.1.l MCIm may purchase CENTREX features (including system
               management, call forwarding, digital facility termination and
               ARS), in accordance with applicable Tariffs.

               2.3.1.2 All service levels and features of CENTREX service
               provided by Bell Atlantic for resale by MCIm shall conform to
               Bell Atlantic's prevailing service requirements and be at Parity
               with the service and features provided to its end user customers.

               2.3.1.3 MCIm may aggregate multiple MCIm subscribers on dedicated
               access facilities. Any aggregation of multiple location
               subscribers may have the effect of changing the retail CENTREX
               service offered under


MCIm-BELL ATLANTIC INTERCONNECTION AGREEMENT - PENNSYLVANIA               II-2
<PAGE>

July 8, 1997                                                     ATTACHMENT II


               applicable Tariff, in which case MCIm must purchase the
               appropriate tariffed service or, if such changed service is not
               available under Tariff, the Parties shall attempt to negotiate a
               separate agreement for such service.

          2.3.2 Federal and State Programs

          When a Bell Atlantic subscriber eligible for the Voluntary Federal
          Subscriber Financial Assistance Program or other similar state
          programs, including Life Line and Link-Up services, chooses to obtain
          Local Resale from MCIm, MCIm shall be responsible for obtaining the
          necessary information for its records regarding such subscriber's
          eligibility.

         2.3.3 Grandfathered Services. Bell Atlantic shall offer for resale to
         MCIm all grandfathered services eligible for resale hereunder. For
         purposes of this Agreement, a grandfathered service is a service that
         Bell Atlantic offers to continue for existing retail subscribers of
         that service, but not to new subscribers.

         2.3.4 N11 Service. Bell Atlantic agrees to offer for resale to MCIm any
         N11 Telecommunications Service it offers under Tariff.

         2.3.5 Contract Service Arrangements, Special Arrangements, and
         Promotions. Bell Atlantic shall offer for resale Telecommunications
         Services, including but not limited to contract service arrangements,
         special arrangements, and promotions, as required by Applicable Law.

         2.3.6 Inside Wire Maintenance Service. [RESERVED]

         2.3.7 Voice Mail Service

               2.3.7.1 [RESERVED]

               2.3.7.2 Bell Atlantic shall make available SMDI-E (Station
               Message Desk Interface-Enhanced) features where available, or
               SMDI (Station Message Desk Interface) features where SMDI-E is
               not available. Bell Atlantic shall make available the MWI
               (Message Waiting Indicator), stutter dialtone, and message
               waiting light feature capabilities. Bell Atlantic shall make
               available CF-B/DA (Call Forward on Busy/Don't Answer), CF/B (Call
               Forward on Busy), and CF/DA (Call Forward/Don't Answer) feature
               capabilities allowing for voice mail services.

         2.3.8 Hospitality Service

               2.3.8.1 Bell Atlantic shall provide all blocking, screening, and
               all other applicable functions available for hospitality (e.g.,
               hospitals, hotels and the like) lines, pursuant to Tariff.


MCIm-BELL ATLANTIC INTERCONNECTION AGREEMENT - PENNSYLVANIA               II-3
<PAGE>

July 8, 1997                                                      ATTACHMENT II


          2.3.9 Telephone Line Number Calling Cards. Bell Atlantic shall
          maintain customer information for MCIm customers who subscribe to
          resold Bell Atlantic Local Service residential or business dial tone
          lines in Bell Atlantic's Line Information Database ("LIDB")in the
          same manner that it maintains information in LIDB on its own similarly
          situated end user customers. Bell Atlantic shall update and maintain,
          on the same schedule that it uses for its own similarly situated end
          user customers, the MCIm customer information in LIDB.

Section 3. Service Functions

    3.1 When Bell Atlantic converts one of its subscribers to MCIm's service,
    Bell Atlantic shall inform MCIm, to the extent such information is available
    through Bell Atlantic's electronic interfaces for CLECs, whether such
    subscriber is currently participating in any program of reduced or exempt
    charges, including those for the indigent, the handicapped, governmental
    bodies and public institutions.

    3.2 Each Party will work cooperatively with the other Party with respect to
    practices and procedures for handling of law enforcement and service
    annoyance calls.

    3.3 The Parties will cooperate in the development of an industry standard of
    "700" number test lines.




MCIm-BELL ATLANTIC INTERCONNECTION AGREEMENT - PENNSYLVANIA               II-4