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                                                                   Exhibit 10.36

                        SUMMARY OF OPERATING AGREEMENT


This Summary of Operating Agreement ("Summary") is entered into this 4th day of
February, 2000, by and between SBC Telecom, Inc. ("SBCT "), a wholly owned
subsidiary of SBC Communications Inc. ("SBC"), Telefonos de Mexico S.A. de C.V.
("Telmex") and Network Access Solutions Corporation ("NAS") (collectively the
"Parties") and sets forth the agreement concerning operational, resale and
marketing interaction between SBCT and NAS and Telmex and NAS in connection with
Telmex and SBC's proposed initial loan and purchase of convertible preferred
shares issued by NAS (the "Equity Investment"). The terms and conditions set
forth herein are binding upon the Parties for a period of one (1) year or until
part or all of this Summary is superceded by one or more of the definitive
agreements contemplated by this Summary.  The Parties shall use their best
efforts to negotiate definitive agreements within sixty (60) days.

1.   RECITALS

     WHEREAS, NAS is a provider of local telecommunications/DSL services with
     operations in Delaware, Maryland, Massachusetts, New York, Pennsylvania,
     Virginia and the District of Columbia;

     WHEREAS, NAS has announced plans to expand aggressively in those states and
     in other states;

     WHEREAS, Telmex, through a wholly owned subsidiary, is making an investment
     in NAS and will have access to NAS services and participation in operating
     and network decisions outlined herein;

     WHEREAS, SBCT has announced plans to offer local telecommunications
     services in geographical areas in at least 30 major metropolitan areas;

     WHEREAS, SBCT intends to provide xDSL service ("xDSL" includes, but is not
     limited to, DSL, ADSL, IDSL and SDSL services) to its customers on a
     nationwide basis, through its own facilities and through arrangements with
     other providers of such services;

     WHEREAS, NAS desires to make modifications to its network and business
     operations in order to more closely align its network and business
     operations with
     the future network and business operations of SBCT and Telmex; and
<PAGE>

     WHEREAS, a major form of consideration that SBCT and Telmex is receiving
     for making the Equity Investment is the execution of this Summary and a
     definitive agreement covering marketing, systems integration, collocation,
     cooperative network development, joint product development and such other
     matters as the Parties may agree (the "Operating Agreements") and a
     definitive resale agreement.

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

2.   SALES AND MARKETING

     a.   NAS and SBCT, and NAS and Telmex, shall each enter into negotiations
          for the purpose of reaching an agreement for SBCT's and / or Telmex's
          resale of NAS's telecommunications services including, but not limited
          to, xDSL services (the "Resale Agreement").  NAS's wholesale prices to
          SBCT and Telmex shall be the lowest of: 1) the lowest wholesale price
          extended by NAS to any other customer; 2) the wholesale price at which
          such services are available from other telecommunications carriers in
          the primary metropolitan statistical area ("PMSA"), provided, however,
          that under this subparagraph (2) NAS's wholesale prices shall include
          a reasonable profit margin; or 3) NAS's direct cost attributable to
          the service, plus a reasonable rate of return, subject to mutually
          agreed upon costing methodologies.

     b.   For services provided by NAS and resold by SBCT and / or Telmex, SBCT
          and NAS, and Telmex and NAS, will jointly establish benchmark service
          level agreements, service intervals and service guarantees due from
          NAS. The Parties will agree on incentives to assure attainment of
          agreed upon service levels.

     c.   SBCT, Telmex and each of their affiliates (including, without
          limitation, Prodigy) shall have the ability to purchase wholesale
          services from NAS; provided, however, that such ability to purchase
          wholesale services shall not apply to Section 3 (Collocation), herein.

     d.   SBCT, Telmex and each of their affiliates (including, without
          limitation, Prodigy) shall have the right to resell NAS
          telecommunications services, each under their own brand, and to
          establish their own marketing programs, sales collateral and other
          promotional material.

     e.   NAS and SBCT, and NAS and Telmex, shall enter into discussions for the
          negotiation of an agreement with NAS to allow NAS to sell certain SBCT
          and / or Telmex services.

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<PAGE>

3.   COLLOCATION

     a.   SBCT, at its option, may lease space from NAS inside any collocation
          space NAS currently has or has ordered from another party where there
          is excess capacity or inside any other space used by NAS to provision
          service. SBCT may deploy equipment of its choosing in the collocation
          space, except that, to the extent that NAS has DSL equipment in place
          or current plans to deploy DSL equipment in that collocation space
          that will deliver xDSL-based services in the timeframe required by
          SBCT and in accordance with SBCT's existing requirements, SBCT shall
          not provide xDSL services using its own equipment located in NAS's
          collocation space, except that SBCT may provide DSL service if no
          valid resale agreement is in place with NAS.  If SBCT changes its
          existing requirements, the deployment of SBCT's DSL equipment in NAS's
          collocation space shall be subject to the Network Committee review
          process for network architecture under the network development
          provisions of this Agreement. If NAS deploys DSL equipment in the
          future in the shared collocation space that is capable of serving
          SBCT's DSL requirements, SBCT shall provision no additional DSL
          customers using SBCT's equipment in NAS's collocation space.  The
          Parties further agree that they will expeditiously work out
          collocation issues with respect to Boston, Miami, Seattle and other
          cities where SBCT is having difficulty meeting its deployment targets.
          If SBCT and NAS have not entered into a resale agreement by June 1,
          2000, then (a) SBCT may not request additional collocation space after
          December 31, 2000, and (b) SBCT may not request additional collocation
          space after June 1, 2000 in any given PMSA if SBCT is already
          collocated or has ordered collocation at 10 or more central offices in
          that PMSA where NAS has collocation space; provided that the
          restrictions set forth in clauses (a) and (b) shall be of no further
          effect if SBCT and NAS enter into a resale agreement after June 1,
          2000.

     b.   The space shall be provided by NAS at the lowest of: 1) the lowest
          price extended by NAS to any other carrier; 2) the price at which such
          space is available from other carriers in the PMSA, provided, however,
          that under this subparagraph (2) NAS's prices shall include a
          reasonable profit margin; or 3) NAS's direct cost attributable to
          providing the space plus a reasonable rate of return, subject to
          mutually agreed upon costing methodologies. To provide SBCT with time
          to assess its collocation space needs, until June 1, 2000, NAS will
          not lease to any third party any collocation space that NAS now
          occupies or has ordered without SBCT's prior consent, nor will NAS
          lease to any third party prior to December 1, 2000 any collocation
          space for which SBCT has advised NAS by June 1, 2000 that SBCT intends
          to lease.

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<PAGE>

     c.   At SBCT's option, NAS shall jointly plan with SBCT where and when to
          acquire new collocation spaces and the physical requirements of NAS's
          new collocation spaces in order to allow SBCT to share collocation
          space with NAS, except that in operating territories where an SBC
          affiliate is an ILEC, NAS shall make the final determination on any
          new collocation space. Each Party will be responsible for its pro rata
          share of the direct costs and mutually acceptable indirect costs of
          the jointly planned collocation space based on each Party's allocated
          space.

     d.   NAS represents that it has or will acquire the contractual ability to
          share collocation space with SBCT under the terms of its
          interconnection agreements or collocation tariffs with the owners of
          the space and that nothing contained in this section shall cause NAS
          to be in breach of any contractual or tariff obligation.

     e.   Telmex and NAS will negotiate in good faith the terms and conditions
          of the collocation and other agreements, consistent with the terms and
          conditions provided to SBCT. NAS will apply the necessary flexibility
          and devote the necessary resources to develop a long term, mutually
          beneficial relationship with Telmex in these matters.

4.  NETWORK COMMITTEE

     a.   SBCT, Telmex and NAS shall establish a Network Committee comprised of
          an equal number of representatives from each Party.  The Network
          Committee will operate under rules agreed to by the Parties.  Except
          within operating territories where an SBC affiliate is the ILEC, the
          Committee shall be responsible for network architecture, network
          buildout, collocation planning and such other functions as the Parties
          may agree upon.  In operating territories where an affiliate of SBC is
          an ILEC, NAS shall be solely responsible for its own network
          architecture, network buildout and collocation planning function.

     b.   Committee Management

          1)  The Network Committee will meet monthly (or as otherwise agreed by
              the Parties) at a time and place agreed upon by the members.
              Meetings may also be called by any Party on 14 days written
              notice to the other Parties, except in cases of emergency, where
              as much notice will be given as practicable.

          2)  Unless agreed by the other Parties, no matter can be finally
              resolved unless it was disclosed in an agenda with sufficient
              particularity to reasonably disclose the nature of the matter.

          3)  A quorum shall consist of at least one member from each Party.

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          4)   Members may participate in a meeting by teleconference and may
               designate an alternate member to participate in a meeting on
               their behalf.

          5)   NAS, Telmex and SBCT shall jointly establish, with the assistance
               of counsel, rules and procedures governing the conduct of
               Committee meetings.

          6)   Each Party will designate a Project Manager to serve as the
               principal contact for matters related to the subject matter of
               this Summary.

          7)   SBCT, Telmex and NAS shall each have as many votes as they have
               representatives on the Network Committee, regardless of whether
               each representative participates in a meeting.

          8)   The Parties shall attempt in good faith to promptly resolve any
               dispute arising out of this Summary or out of the definitive
               agreements contemplated herein ("Dispute") by negotiation between
               the designated Project Manager for each Party.  Any Party may
               provide written notice of a Dispute, which will set forth the
               nature of the dispute and the identity of representatives in
               addition to the Project Manager who will attend settlement
               meetings. After the receipt of a written notice of a Dispute, the
               representatives of the Parties shall meet as soon as practicable
               at mutually acceptable times and places.  If a Dispute has not
               been resolved within 30 days of the receipt of written notice,
               the Dispute shall be referred to the CEO of NAS, the President of
               SBCT, and the Senior Officer of Telmex for resolution.

5.  NETWORK ARCHITECTURE

     a.   The Network Committee will jointly test, evaluate and approve proposed
          network platforms, network equipment and network architecture to be
          used in NAS's network.

     b.   NAS will deploy the network platforms and establish network
          architecture, and will use the equipment vendors, approved by SBCT and
          Telmex, provided however, that SBCT or Telmex shall not require NAS to
          use network platforms or establish network architecture which would
          have a material adverse effect on NAS's ability to provide service to
          its customers nor shall anything preclude NAS from using any network
          platforms or network architecture it wishes-- provided that such
          network platforms and network architecture do not adversely affect the
          services SBCT and / or Telmex obtains or has requested from NAS.

                                       5
<PAGE>

6.  NETWORK BUILDOUT

     a.   The Network Committee will jointly evaluate and approve proposals to
          build out new NAS network facilities, which may include, but is not
          limited to, transport, central offices, collocation and equipment
          ("Network Facilities").  NAS will build out new Network Facilities as
          directed by the unanimous vote of the Network Committee.

     b.   In the event that NAS wants to build out new Network Facilities and
          cannot obtain the agreement of the SBCT and Telmex members(s), nothing
          in this section shall prevent NAS from building out such Network
          Facilities.

     c.   In the event that SBCT or Telmex wants NAS to build out new Network
          Facilities and cannot obtain the agreement of the NAS members(s), NAS
          shall build out the Network Facilities as a Mandatory Project as set
          forth in subparagraph (e) below.

     d.   Notwithstanding any other provision of this Section 6 (Network
          Buildout) NAS shall establish new Network Facilities to support the
          provision of xDSL services in the PMSAs listed in Attachment A.  SBCT
          shall have the right to amend the list upon reasonable notice.  The
          xDSL service shall meet SBCT's specifications and shall be deployed in
          accordance with SBCT's reasonable timeline.

     e.   Mandatory Project

          1)   Should a Network Facilities build out proposal fail to receive
               the necessary approval of the Network Committee due to the
               failure of NAS to support it, either SBCT or Telmex may require
               NAS to initiate the proposal as a Mandatory Project. NAS shall
               commence efforts on the Mandatory Project within one (1) month of
               receiving notice from SBCT or Telmex to proceed with the
               Mandatory Project.

          2)   Notwithstanding the immediately preceding subparagraph 1), SBCT
               or Telmex may, instead of pursuing the proposal as a Mandatory
               Project, undertake the project on its own or with a third party.
               In such case, NAS will cooperate with SBCT or Telmex and will use
               its best efforts to integrate a Mandatory Project into the
               existing infrastructure of NAS's network.

          3)   If NAS is required to complete a Mandatory Project, SBCT and / or
               Telmex shall pay NAS: (i) all reasonable, identifiable fully
               loaded direct expenses associated with the Mandatory  Project,

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<PAGE>

               plus (ii) the reasonable cost of capital investments directly
               required by the Mandatory Project, less (iii) any cost savings,
               tax benefits or other benefits attributable to the Mandatory
               Project.  Cost savings shall be estimated, and then adjusted when
               actual data becomes available. Mandatory Projects shall be
               subject to mutually agreed upon costing methodologies.

          4)   At Telmex's or SBCT's option, SBCT or Telmex will either: (i) own
               all aspects of the Mandatory Project, including facilities,
               intellectual property and rights to use; or (ii) lease from NAS
               the exclusive rights to use all aspects of the Mandatory Project
               for the life of the equipment for $1 per year plus operating
               costs.

          5)   SBCT and Telmex shall have reasonable audit rights.

7.  SYSTEMS INTEGRATION

     a.   The Parties use certain systems to process, analyze, store and
          retrieve data.  These systems include, but are not limited to, revenue
          systems (which include, among others, systems for pre-ordering,
          ordering, service activation, service assurance and billing) and
          administrative systems (which include, among others, payroll,
          personnel and accounting systems) (collectively, the "Data Systems").

     b.   NAS and SBCT, and NAS and Telmex, shall, as soon as reasonably
          practicable following the execution of Resale Agreements, develop
          electronic methods of exchanging information related to pre-ordering,
          ordering, service activation, service assurance and billing for NAS
          services under their separate resale relationships. NAS and SBCT, and
          NAS and Telmex, will establish manual processes for use until
          electronic processes are in place.

     c.   NAS, Telmex and SBCT shall each bear its own cost of developing and/or
          otherwise providing the manual and electronic methods of information
          exchange.  Costs for all shared facilities or capabilities shall be
          borne equally by the Parties on a pro-rata basis.

8.  PRODUCT DEVELOPMENT

     a.   SBCT and NAS, and Telmex and NAS, shall actively participate in joint
          product development processes, including but not limited to,
          identification and evaluation of new products and product
          functionalities, and decisions on whether to develop or acquire the
          desired product functionality.

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<PAGE>

     b.   SBCT and NAS, and Telmex and NAS, will agree as to both the
          functionality of jointly deployed products and the timing of the
          marketing and delivery of such products.

     c.   To the extent joint product development results in characteristics not
          otherwise available in the market, the Parties (either SBCT and NAS or
          Telmex and NAS) will agree on the terms and conditions upon which
          these products are to be made available to customers and other
          telecommunications carriers.

     d.   SBCT and NAS, and Telmex and NAS, will share intellectual property
          rights in jointly developed products.

9.   TERM

     The term of the definitive Operating Agreements and Resale Agreements shall
     be five (5) years from the date such agreements are executed.

10.  CONFIDENTIALITY

     Except to the extent required to be disclosed by law or pursuant to an
     order of a court or agency with jurisdiction, each Party shall hold in
     confidence the provisions of this Summary and any proprietary or
     confidential information received pursuant to the negotiations surrounding
     this Summary and shall use such proprietary or confidential information
     only to fulfill its obligations or enforce its rights under this Summary or
     to consummate a definitive agreement between the Parties covering the
     subject matter of this Summary. Each Party shall use the same efforts to
     safeguard any proprietary or confidential information received pursuant to
     this Summary as it uses to protect its own proprietary or confidential
     information.  Each Party shall have the right to enforce this
     confidentiality obligation by injunctive relief, including specific
     performance.  This confidentiality obligation shall remain in effect for a
     period of twelve (12) months after the expiration of this Summary.

11.  COMPLIANCE WITH LAWS

     Nothing in this Summary shall obligate a Party to take any action that
     violates any applicable governmental law, regulation, order, or policy of
     the FCC or any other governmental entity, including, but not limited to,
     any provisions of the Federal Communications Act of 1934, as amended
     ("Act") and the antitrust laws of the United States and the respective
     States.  In no event shall a Party be obligated to perform any acts or to
     abstain from performing any act if, in the Party's reasonable judgment,
     after consulting with the other Parties, performance or non-performance
     will violate the Act or any applicable law regulation, order, policy of the
     FCC, any antitrust laws, or any other law or regulation.

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<PAGE>

12.  OTHER TERMS AND CONDITIONS

     The definitive Operating Agreement between the Parties shall, at a minimum,
     contain terms and conditions covering intellectual property rights,
     prohibition on solicitation of employees, transition upon termination,
     representations and warranties, indemnification, limitation of liability
     and coordination on publicity.

13.  CHANGE IN CONTROL

     In the event of an NAS Change in Control Event, as defined in the Stock
     Purchase Agreement by and between SBC and NAS, and Telmex and NAS, SBCT and
     Telmex shall have the right to terminate the Operating Agreements and the
     Resale Agreements for 180 days after the NAS Change in Control Event by
     providing notice to NAS, and such termination shall occur 60 days after
     giving such notice.

14.  MISCELLANEOUS

     Nothing in this Summary permits NAS to influence or control any aspect of
     network deployment or operation of Telmex, SBC, or an SBC affiliate, within
     SBC's ILEC operating territory.


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<PAGE>

IN WITNESS WHEREOF, the Parties hereto have signed this Summary, or have caused
this Summary to be signed in their respective names by an officer, hereto duly
authorized, on the date first written above.


SBC Telecom, Inc.

By: ______________________________

Name: __________________________

Title: ___________________________



Telefonos de Mexico S.A. de C.V.

By: ____________________________

Name: __________________________

Title: ___________________________



Network Access Solutions Corporation

By: _____________________________

Name: __________________________

Title: ___________________________

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                                 ATTACHMENT A

<TABLE>
<CAPTION>
          PMSA's For NAS Deployment of Network Facilities

<S>                                     <C>
          Boston                        Nashville
          Miami                         Raleigh
          Seattle                       Norfolk
          Ft. Lauderdale                Louisville
          New York City                 New Orleans
          Washington, DC                Tucson
          Baltimore
          Atlanta
          Philadelphia
          Phoenix
          Minneapolis
          Denver
          Nassau, NY
          Bergen-Passaic, NJ
          Newark, NJ
          Middlesex, NJ
          Orlando
          Tampa
          Salt Lake City
          West Palm Beach
          Portland
          Charlotte
          Buffalo
          Memphis

</TABLE>

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