<PAGE>   1
                                                                    EXHIBIT 10.1

NOTE: REDACTED PORTIONS HAVE BEEN MARKED WITH (***). THE REDACTED PORTIONS ARE
SUBJECT TO A REQUEST FOR CONFIDENTIAL TREATMENT THAT HAS BEEN FILED WITH THE
SECURITIES AND EXCHANGE COMMISSION.












                              PROCUREMENT AGREEMENT

                                     BETWEEN

                        QWEST COMMUNICATIONS CORPORATION

                                       AND

                     ADVANCED SWITCHING COMMUNICATIONS, INC.


















                                     - i -
<PAGE>   2
NOTE: REDACTED PORTIONS HAVE BEEN MARKED WITH (***). THE REDACTED PORTIONS ARE
SUBJECT TO A REQUEST FOR CONFIDENTIAL TREATMENT THAT HAS BEEN FILED WITH THE
SECURITIES AND EXCHANGE COMMISSION.


                                TABLE OF CONTENTS

<TABLE>
<S>                                                                                  <C>
1. DEFINITIONS........................................................................1


2. SCOPE............................................................................. 6


3. SUPPLIER OBLIGATIONS.............................................................. 8


4. QWEST OBLIGATIONS................................................................. 9


5. GOVERNANCE....................................................................... 10


6. PRICING.......................................................................... 11


7. ORDERING......................................................................... 11


8. DELIVERY AND SHIPMENT............................................................ 12


9. PAYMENT TERMS.................................................................... 14


10. PRODUCT REQUIREMENTS............................................................ 15


11. CHANGES IN THE WORK............................................................. 17


12. ACCEPTANCE PERIOD;ACCEPTANCE.....................................................18


13. SOFTWARE........................................................................ 20


14. (***)........................................................................... 25


15. INFRINGEMENT WARRANTY AND INDEMNITY............................................. 26


16. KNOW HOW AND NEW TECHNOLOGY......................................................27


17. WARRANTY........................................................................ 28


18.  GENERAL INDEMNITY...............................................................30


19. LIMITATION OF LIABILITY......................................................... 31


20. CONFIDENTIALITY................................................................. 31


21. TERMINATION, SURVIVAL........................................................... 33


22. FORCE MAJEURE................................................................... 34


23. ASSIGNMENT...................................................................... 35


24. JOINT WORK PRODUCT.............................................................. 35
</TABLE>


                                     - ii -
<PAGE>   3
NOTE: REDACTED PORTIONS HAVE BEEN MARKED WITH (***). THE REDACTED PORTIONS ARE
SUBJECT TO A REQUEST FOR CONFIDENTIAL TREATMENT THAT HAS BEEN FILED WITH THE
SECURITIES AND EXCHANGE COMMISSION.



<TABLE>
<S>                                                                                 <C>
25. DISPUTES.......................................................................  35


26. RELATIONSHIP OF THE PARTIES..................................................... 36


27. AMENDMENT....................................................................... 37


28. COMPLIANCE WITH LAWS............................................................ 37


29. CONSTRUCTION/HEADINGS........................................................... 38


30. NO WAIVER....................................................................... 38


31. SEVERABILITY.................................................................... 38


32. COUNTERPARTS.................................................................... 38


33. CHOICE OF LAW................................................................... 38


34. REMEDIES........................................................................ 39


35. IMMIGRATION REFORM AND CONTROL ACT.............................................. 39


36. IMPORT/EXPORT....................................................................39


37. PUBLICITY........................................................................39


38. NOTICES......................................................................... 40


39. INSURANCE REQUIREMENTS.......................................................... 41


40. ORDER OF PRECEDENCE............................................................. 42


41. ENTIRE AGREEMENT...................................................................
</TABLE>


                                     - iii -
<PAGE>   4



NOTE: REDACTED PORTIONS HAVE BEEN MARKED WITH (***). THE REDACTED PORTIONS ARE
SUBJECT TO A REQUEST FOR CONFIDENTIAL TREATMENT THAT HAS BEEN FILED WITH THE
SECURITIES AND EXCHANGE COMMISSION.





THIS PAGE LEFT INTENTIONALLY BLANK



                                     - iv -


<PAGE>   5



                                    AGREEMENT

        This procurement agreement is made and entered into by and between
Advanced Switching Communications, Inc. ("Supplier"), a Delaware corporation,
with a place of business at 8330 Boone Blvd., Fifth Floor, Vienna, VA 22182, and
Qwest Communications Corporation, a Delaware corporation, having its principal
offices and place of business at 555 Seventeenth Street, Suite 1000, Denver,
Colorado 80202 ("Qwest") (Supplier and Qwest each being referred to herein as a
"Party" and collectively as the "Parties").

        NOW, THEREFORE, in consideration of the foregoing and of the mutual
promises and covenants hereinafter expressed, the Parties hereto agree as
follows:


1.      DEFINITIONS

        1.1    The terms used in this Agreement shall have their normal or
               common meaning, except that in addition to terms defined at other
               places in this Agreement, the following terms shall have the
               following meanings for the purposes of this Agreement, the
               Schedules and any attachments thereto:

                (a)     "Acceptance" shall have the meaning given to it in
                        Section 12.2.

                (b)     "Acceptance Period" shall have the meaning set forth in
                        Section 12.1.

                (c)     (b)"Affiliate" means (i) any individual, corporation,
                        partnership, joint venture, limited liability company,
                        limited liability partnership, practice, association,
                        joint stock company, trust, unincorporated organization
                        or other venture or business vehicle (each an "Entity")
                        in which a Party owns a (***) or greater equity
                        interest; (ii) any Entity which, directly or indirectly,
                        is in control of, is controlled by or is under common
                        control with a Party, as applicable, after applying the
                        attribution rules of Section 318 of the Internal Revenue
                        Code; or (iii) any other Entity agreed by the Parties.
                        For the purposes of this Agreement, control of an Entity
                        ("Control") shall include the power, directly or
                        indirectly, whether or not exercised (i) to vote (***)
                        (or such lesser percentage as is the maximum allowed to
                        be owned by a foreign corporation in a particular
                        jurisdiction) or more of the securities or other
                        interests having ordinary voting power for the election
                        of directors or other managing authority of such Entity;
                        or (ii) to direct or cause the direction of the
                        management or policies of such Entity, whether through
                        ownership of voting securities, partnership interest or



                                     - 1 -
<PAGE>   6

                        equity, by contract or otherwise. Current Qwest
                        Affiliates are listed in within thirty (30) days of the
                        Effective Date, the Parties will amend this Agreement by
                        the addition of Schedule A (Approved Affiliates)
                        containing the names of Qwest Affiliates who have been
                        designated by Qwest and who have met the credit
                        standards referenced in Section 2.4 (the "Approved
                        Affiliates").

                (d)     Agreement" means this agreement including the schedules
                        described in Section 2.5 and attached hereto (the
                        "Schedules").

                (e)     "Class A Change" means a modification, revision,
                        replacement, (***) of existing Supplier manufactured
                        Product (***), provided that the Product incorporating
                        such change, is at least (***) as the same Product prior
                        to incorporation of such change.

                (f)     "Current Release" means the latest Version or Release of
                        the Software which has been approved by Supplier for
                        commercial use.

                (g)     "Days" or "days" means calendar days, unless otherwise
                        provided herein.

                (h)     "Documentation" means the user, technical and operating
                        manuals, including the operating instructions, guides
                        and manuals, necessary to enable Qwest properly to use
                        and maintain the Products.

                (i)     "Effective Date" means September 1, 2000.

                (j)     "Enhancement" means any modification or revision to the
                        Software that Qwest may opt to license, which (i)
                        substantially improves existing functions or features,
                        including functions and features for which Qwest has
                        already been granted a license, or (ii) adds new
                        functions or features.

                (k)     "Equipment" means hardware, equipment, embedded
                        software, including firmware, and all physical
                        components, including cabling, required by this
                        Agreement to be provided by Supplier.

                (l)     "Form, Fit or Function" shall have the following
                        meaning. "Form" means shape; "Fit" means physical size
                        or mounting arrangement (e.g., electrical or mechanical
                        connections); and "Function" means features and
                        capabilities.



                                     - 2 -
<PAGE>   7

                (m)     "Hardware" means the hardware (and any associated
                        firmware) that is part of the Equipment.

                (n)     "Incremental Software Update" or "ISU" means any
                        modification or revision to the Software, other than
                        Enhancements, that (i) (***); (ii) supports new releases
                        of third party operating systems with which the Software
                        is designed to operate; (iii) supports new Equipment;,
                        (iv) improves the performance of the Software; or (v)
                        provides other updates (***). If a modification or
                        revision described in clause (ii), (iii) or (iv) above
                        adds new functions or features or substantially improves
                        the network performance, it shall be deemed to be an
                        Enhancement with respect to those new functions and
                        features.

                (o)     "Installation Site" means the building, complex of
                        buildings or remote site at which any of the Products
                        are installed.

                (p)     "Intellectual Property Rights" mean all forms of
                        intellectual property rights and protections including,
                        without limitation:

                        (i)     All right, title and interest in and to all
                                letters patent and all filed, pending or
                                potential applications for letters patent,
                                including any reissue, reexamination, division,
                                continuation or continuation-in-part
                                applications throughout the world now or
                                hereafter filed;

                        (ii)    All right, title and interest in and to all
                                trade secrets, and all trade secret rights and
                                equivalent rights arising under the common law,
                                state law, federal law and laws of foreign
                                countries;

                        (iii)   All right, title and interest in and to all mask
                                works, copyrights, other literary property or
                                author's rights, whether or not protected by
                                copyright or as a mask work, arising under
                                common law, state law, federal law and laws of
                                foreign countries; and

                        (iv)    All right, title and interest in and to all
                                proprietary indicia, trademarks, trade names,
                                service marks, symbols, trade dress, logos
                                and/or brand names protected under common law,
                                state law, federal law and laws of foreign
                                countries.



                                     - 3 -
<PAGE>   8

                        (m)     "Media" means the media on which the Software
                                and the Documentation for the Software are
                                recorded or printed as provided to Qwest by
                                Supplier.

                        (n)     "Network Compatible" or "Network Compatibility"
                                with respect to a Product means that (i) the
                                Product will comply with the applicable (***)
                                and (***) standards in effect on the date that
                                Qwest issues the Purchase Order, and any other
                                standards agreed by the Parties in writing; (ii)
                                the Product can be operationally deployed in
                                Qwest's network (***); and (iii) the Product
                                will (***). Qwest in its sole discretion may
                                waive the foregoing compatibility requirements
                                for the purpose of deploying new technology
                                offered by Supplier during the Term.

                        (o)     "Nonconformity" means an instance of failure of
                                a Product to be Operative.

                        (p)     "Object Code" means machine-readable computer
                                instructions that can be executed by a computer.

                        (q)     "Operating Platform" means the computer
                                equipment, hardware and operating system, which
                                execute the Object Code and on which the
                                Software runs.

                        (r)     "Operative" means (i) conforming in all respects
                                to the Specifications, the requirements of this
                                Agreement and the applicable Purchase Orders in
                                effect at the time Supplier accepts the Purchase
                                Order, and (ii) Network Compatible.

                        (s)     "Prior Agreement" means the agreement between
                                Supplier and Qwest dated June 30, 2000.

                        (t)     "Products" mean the Equipment, Software, and
                                Documentation, including any part thereof,
                                described in the Schedules, which this Agreement
                                requires Supplier to furnish or that Supplier
                                furnishes hereunder. Qwest and Supplier may
                                amend the Schedules by written agreement to
                                include other products offered for sale by
                                Supplier.

                        (u)     "Program Manager" means the senior manager of a
                                Party who shall have overall responsibility for
                                the day-to-day management and administration of
                                this Agreement and who shall work together with
                                the other Party's Program Manager to facilitate
                                an efficient delivery of Products and Services.



                                     - 4 -
<PAGE>   9

                        (v)     "Purchase Order" means the written instrument
                                described in Section 7, a form of which is
                                attached hereto as Schedule B, under which Qwest
                                orders and Supplier delivers Products or
                                Services under this Agreement.

                        (w)     "Release" means any revision, modification,
                                replacement, or correction to the Software,
                                including an Enhancement or ISU, that Supplier
                                makes available to any of its customers for use.

                        (x)     "Segment" means a continuous route within the
                                Qwest network.

                        (y)     "Services" mean work performed and labor
                                provided by Supplier, including, but not limited
                                to, design, engineering, installation and
                                implementation of Products, Software testing,
                                warranty, technical support, training and
                                similar activities.

                        (z)     "Software" means any software, including Object
                                Code, Source Code and firmware that is delivered
                                to Qwest under this Agreement, inclusive of the
                                Supplier intellectual property therein, whether
                                or not the subject of any patent or copyright,
                                issued or pending. Software may include programs
                                used to create, enhance, test or maintain any
                                Product delivered under this Agreement. Software
                                includes all Releases and Versions.

                        (aa)    "Source Code" means the human-readable code from
                                which a computer can compile or assemble the
                                Object Code of the Software, together with a
                                description of the procedure for generating the
                                Object Code.

                        (bb)    "Specifications" mean the functional,
                                performance, design, operational, and physical
                                characteristics of a Product or System, as
                                described in the applicable ANSI and ISO
                                standards and Supplier proposal. If an ANSI or
                                ISO standard is not available for a new Product,
                                the formal specification developed by Supplier
                                and provided to Qwest shall be used.

                        (cc)    "Supplier Personnel" mean any employees,
                                trainers, or other support personnel provided by
                                Supplier under this Agreement whether or not
                                employed by Supplier (to the extent that such
                                are permitted elsewhere under this Agreement).
                                Supplier shall be performing under this
                                Agreement at all times as an independent
                                contractor to Qwest, and the Supplier Personnel
                                shall not be considered as employees or agents
                                of Qwest.



                                     - 5 -
<PAGE>   10

                (dd)    "System" means an Operative combination of Products
                        designed, engineered, furnished, installed or
                        implemented by Supplier under this Agreement.

                (ee)    "Version" means a Release of Software intended for use
                        with a particular make and model of computer or a
                        particular operating system.

                (ff)    "Warranty Period" means the time period specified in
                        Section 17.

        1.2     Additional definitions appear elsewhere in the recitals and
                subsequent Sections of this Agreement.


2.      SCOPE

        2.1     The initial term of this Agreement ("Initial Term") commences on
                the Effective Date and continues until December 31, 2002, unless
                earlier terminated in accordance with other provisions of this
                Agreement or unless extended in writing by the Parties . At its
                option, Qwest may extend the Initial Term for a period of up to
                six (6) months (the "Extended Term") by written notice to
                Supplier prior to the expiration date of this Agreement (the
                Extended Term, if any, together with the Initial Term, are
                hereinafter the "Term").

        2.2     (a) Subject to the terms and conditions of this Agreement,
                including its Schedules, during the Initial Term, Qwest will
                make purchases of Products under this Agreement as follows:
                (***). The above amounts are net of any discounts Qwest receives
                on the price of the Products.

                (b) Supplier will complete development and deployment of the
                products and deliverables as set forth in the attached (***). If
                Supplier (a) fails to meet any purchase order delivery date due
                to a delay or failure to have the products described in (***)
                available for successful general availability as of their
                corresponding delivery dates, (b) otherwise fails to have the
                products described in (***) available for successful general
                availability as



                                     - 6 -
<PAGE>   11

                of their corresponding delivery dates, or (c) with regards to
                (***), another Supplier offers Qwest better pricing, density
                models and functionality due to technology changes, Qwest, at
                its sole option, may terminate this Agreement for Cause and
                have no further commitment obligation, provided that ASC has
                the opportunity to match any bonafide offers within (***) from
                date of notification from Qwest.

                (c) Subject to Section 21.3, all purchases of Products from
                Supplier and its Affiliates by Qwest and Qwest Affiliates will
                be credited toward the (***). Any purchases made in excess
                of (***).

        2.3     This Agreement shall apply to the transactions in which Supplier
                furnishes the Products described in the Schedules to Qwest
                during the Term.

        2.4     Approved Affiliates may issue a Purchase Order under this
                Agreement. Affiliates who are not Approved Affiliates may become
                Approved Affiliates if they (i) (***) which fulfillment of (***)
                Supplier will determine within (***) after notice from (***) and
                (ii) (***) of this Agreement. If Supplier has not provided
                written acknowledgement of an Affiliate's failure to meet such
                credit standards within (***), the Affiliate shall be deemed to
                have been authorized to purchase under this Agreement and shall
                be deemed an Approved Affiliate. If there has been a transfer of
                (***) or more of the assets of any Approved Affiliate who (i) is
                seeking to place an new Purchase Order under this Agreement or
                (ii) has an outstanding Purchase Order of (***) or more,
                Supplier shall have the right to (***) Purchase Order and the
                right to review such Approved Affiliate's qualification as such.
                If, upon review, the Approved Affiliate no longer qualifies for
                approval pursuant to this Section, Supplier shall have the right
                to (***), and it shall (***) to place Purchase Orders under this
                Agreement without the satisfaction of another (***).

        2.5     The following Schedules attached hereto are an integral part of
                this Agreement and are incorporated herein by reference.

                A.      Approved Affiliates

                B.      Form Purchase Order [Qwest]

                C.      (***)

                D.      (***)

                                     - 7 -
<PAGE>   12

                E.      (***)

                F.      (***)

                G.      (***)

                H.      Third Party Items

                I.      (***)

                J.      (***)

                K.      Pending Infringement Claims

                L.      Confidentiality Agreement

                M.      Product Specification


3.              SUPPLIER OBLIGATIONS

        3.1     Supplier shall perform all Services and deliver all Products
                necessary to fulfill the requirements of this Agreement and
                shall perform all work in a professional and workmanlike manner,
                in accordance with all requirements, acceptance criteria and
                Specifications of this Agreement and the warranties provided
                hereunder. Among its obligations, Supplier shall:

                (a)     complete all tasks required by a an accepted Purchase
                        Order by providing all necessary resources, personnel,
                        materials and equipment;

                (b)     adhere to agreed delivery dates;

                (c)     supervise and manage the overall Supplier's effort under
                        each Purchase Order and this Agreement and coordinate
                        its efforts with the Qwest Program Manager; and

                (d)     provide competent personnel of sufficient experience and
                        expertise to fulfill the goals of this Agreement.

        3.2     In addition to other requirements contained in this Agreement,
                Supplier will consider the following Qwest objectives in its
                delivery of Products and Services under this Agreement:

                (a)     ensuring a smooth transition from the existing products
                        to new Products provided hereunder as possible;



                                     - 8 -
<PAGE>   13

                (b)     training; and

                (c)     using an orderly approach for any significant
                        implementation of new Products.

        3.3     Supplier is responsible for providing qualified personnel in the
                quantities and of the experience necessary to fulfill the
                requirements of this Agreement. When requested by Qwest,
                Supplier shall provide the names of Supplier Personnel providing
                Services at Qwest sites.


4.      QWEST OBLIGATIONS

        4.1     By the end of the third quarter of each calendar year, Qwest
                will provide Supplier with a forecast of Qwest's estimated
                Product requirements for the next calendar year (each a
                "Forecast"). Qwest will update this Forecast each quarter and
                when significant changes occur. The Forecast shall be for
                planning purposes only and shall not represent Qwest's
                commitment to purchase any or all such Products or create any
                other obligation whatsoever by Qwest.

        4.2     Qwest agrees that all Supplier Personnel who are approved in
                writing by Qwest to be involved in any effort under this
                Agreement will be provided reasonable access to Qwest's premises
                during mutually agreed times as necessary. Supplier Personnel
                shall comply with site and security regulations specified by
                Qwest.

        4.3     For all Products not on Supplier's price list ("Non-Price List
                Products"), Qwest shall issue (***) to Supplier no later than
                (***) prior to the required equipment ship date for Non-Price
                List Products included in the Forecast. Non-forecasted Non-Price
                List Products equipment will require (***) advance notice to
                Supplier. Supplier's sales engineering shall issue a written
                proposal to Qwest for Product purchases within two weeks of
                receipt (***), or a reasonable time thereafter as necessary to
                complete the proposal.

5.      GOVERNANCE

        5.1     Key Personnel.

                Supplier agrees that each of the following Supplier Personnel
                ("Key Personnel") who are currently in the following positions
                will devote substantially her or his full time and effort to the
                Qwest account.

                                     - 9 -
<PAGE>   14

<TABLE>
<CAPTION>
               NAME                         POSITION
               ----                         --------
<S>                          <C>
               (***)         Director
               (***)         Engineer
</TABLE>

                Before assigning an individual as a replacement for any of the
                Key Personnel, Supplier will notify Qwest of the proposed
                assignment, will provide Qwest with a description of the
                education and experience and any other job-related information
                about the individual reasonably requested by Qwest and will
                introduce (either by telephone or, if requested by Qwest in
                person) the individual to appropriate Qwest representatives.
                Thereafter, if Qwest consents, in writing, to the proposed
                assignment within (***) such consent not to be unreasonably
                withheld, Supplier will assign the individual as a Key Personnel
                replacement.

        5.2     Meetings.

                By (***), the Parties will mutually determine appropriate
                intervals for periodic meetings to be held between
                representatives of Qwest and Supplier. At a minimum, these
                meetings will include the following:

                (a)     (***) meeting between the respective project management
                        teams;

                (b)     (***) management meeting to review Supplier's progress
                          under (***) and such other matters as appropriate; and

                (c)     (***) executive review meeting to review relevant
                          contract and (***) issues.

                Each Party's Program Manager or individual designated by the
                Program Manager will attend each meeting.

        5.3     Personnel.

                Qwest reserves the right to require replacement of any Supplier
                employee or contractor performing work for Supplier under this
                Agreement if Qwest is reasonably dissatisfied with the
                performance of that individual and reasonably determines that
                the continued assignment of such individual is not in the best
                interest of Qwest. Qwest shall give Supplier written notice
                requesting that the individual be replaced and stating the
                reasons for the request. Supplier shall replace such individual
                with a person of suitable ability and qualifications within
                (***) from the request or such additional time period as may be
                reasonably required under the circumstances.



                                     - 10 -
<PAGE>   15

        5.4     Reports.

                Supplier shall provide to Qwest written progress reports as
                agreed by the Parties, on at least a weekly basis, delivered by
                electronic mail followed by a paper copy to Qwest's designated
                representative. Progress reports shall include: (i) the status
                of delivery under all open Purchase Orders for Products; (ii)
                items completed during the reporting period; (iii) items to be
                completed within the next reporting period; (iv) open action
                items; and (v) any other action items required by Qwest, listing
                the party responsible for such actions.


6.      PRICING

        Qwest shall receive a (***) the prices set forth on (***).


7.      ORDERING

        7.1     (a) Qwest (or an Approved Affiliate) shall issue Purchase
                Orders, a form of which is attached hereto as Schedule B, to
                acquire all Products under this Agreement. All Purchase Orders
                must be submitted (***) prior to the delivery date designated in
                the Purchase Order (with respect to (i), below) or as agreed
                upon by the Parties (with respect to (ii), below) (the "Order By
                Date"). Upon request by Qwest, the Parties will in good faith
                discuss a shorter period for Purchase Order submission. (i) For
                all Purchase Orders less than or equal to (***) of the Forecast
                amount which are submitted prior to the Order Date, Supplier
                agrees to be bound by the designated delivery date.

                (ii) For all Purchase Orders that are in excess of (***) of the
                Forecast or are submitted after the Order Date, (***).

        7.2     Supplier shall confirm and accept the Purchase Order in writing
                in accordance with (***) at which point the Purchase Order shall
                become a binding commitment. Subject to Section 7.1, Supplier
                agrees to accept all Purchase Orders issued by Qwest under this
                Agreement provided that such Purchase Orders conform with the
                requirements of this Agreement.

        7.3     Any changes to a Purchase Order shall be made in writing.

        7.4     All Purchase Orders issued hereunder by Qwest or the Approved
                Affiliates shall reference this Agreement and shall be deemed to
                incorporate and be governed solely by the terms and conditions
                set forth herein. Any changes to the terms and conditions of the
                Agreement contained in any Purchase



                                     - 11 -
<PAGE>   16

                Order or Supplier's written acknowledgement thereof shall have
                no force or effect.


8.      DELIVERY AND SHIPMENT

        8.1     Supplier shall deliver Products as required under this Agreement
                to Qwest or Approved Affiliates (as applicable) at the locations
                and at the times specified by Qwest or Approved Affiliates (as
                applicable), and agreed to by Supplier in an accepted Purchase
                Order, this Agreement or as otherwise agreed in writing by the
                Parties. For purposes of this Section 8, "Buyer" shall mean
                Qwest or its Approved Affiliate, as applicable. Supplier shall
                deliver all Products and Services at the designated location in
                a timely manner.

        8.2     Supplier shall ship all Products purchased pursuant to this
                Contract, freight prepaid, (***) designated in the Purchase
                Order or to such other location as the Parties may agree
                ("Destination"). The method of shipment shall be consistent with
                the nature of the Products and hazards of transportation. Risk
                of loss for all Products ordered in accordance with this
                Agreement shall pass to Qwest (***) except loss or damage
                attributable to the Supplier's fault or gross negligence. Such
                loss, damage, or destruction shall not release Supplier from any
                obligations hereunder. Upon delivery the risk of loss or damage
                shall be borne by the Qwest. Title to Products (excluding
                Software) shall pass to Qwest upon delivery to the Destination.
                Supplier shall convey good title, free from any claim or
                encumbrance, for all Products (excluding Software) delivered to
                Qwest under this Agreement. Supplier will pack the Products
                purchased hereunder for transport in accordance with its
                commercial standards and will deliver the Products to a carrier
                of the mode of transportation selected by Supplier unless
                otherwise agreed upon in writing by the Parties.

        8.3     If Supplier fails to meet any agreed schedule, Qwest, without
                limiting its other rights or remedies as specified herein, may
                direct expedited routing of Products (***). Qwest shall not be
                liable for Supplier's commitments or production arrangements in
                excess of the amount, or in advance of the time, necessary to
                meet Qwest's delivery schedule. Delivery shall not occur (***)
                in advance of the delivery date. If delivery occurs prior to the
                period authorized above and designated storage has not already
                been established by Supplier, Qwest may (i) return delivered
                items at Supplier's expense for proper delivery, or (ii) place
                delivered items in storage at Supplier's expense until the
                scheduled date of delivery.



                                     - 12 -
<PAGE>   17

        8.4     The Parties agree that for all shipments that otherwise meet the
                designated delivery dates (a) any failure to supply all Products
                ordered in a single shipment or (b) any partial shipment or
                delivery of an Order in installments shall not constitute a
                breach of this Agreement provided that Supplier has received
                Buyer's prior written approval of the same, such approval not to
                be unreasonably withheld.

        8.5     Performance Incentives

                (a)     Subject to Section 21, for accepted Purchase Orders of
                        Products with an aggregate value of (***)or more,
                        Supplier and Qwest agree that it may be difficult, if
                        not impossible, to accurately determine the amount of
                        damages that Qwest may incur, if Supplier fails to
                        deliver the Products as scheduled. Accordingly, if
                        delivery has not occurred with respect to any Product,
                        Segment or System within (***) after the scheduled
                        delivery date, Buyer shall be entitled to daily
                        performance incentives in a specified and predetermined
                        amount of (***) of the total price of the affected
                        Product, Segment or System, per day late, up to a
                        maximum of (***) of total price of the Product, Segment
                        or System ("Performance Incentive").

                (b)     Buyer shall not assess Performance Incentives to the
                        extent that Supplier has been delayed by Buyer not
                        fulfilling its obligations under this Agreement.

        8.6     Equipment Tracking Data. Supplier shall provide Qwest with
                quarterly reports containing the following information in a
                jointly developed format. The reports shall contain Equipment
                information, including: (1) a description of the Equipment; (2)
                Supplier part number; (3) Equipment destination by building
                (final); (4) shipping date; and (5) Supplier serial number.

        8.7     In the event that Qwest installs a bar coding system for its
                fixed assets, Supplier shall apply a Qwest asset tag (to be
                supplied by Qwest) at either the manufacturing site or at the
                point of shipment for the Equipment in a manner that allows
                Qwest to easily read the asset tag. Supplier may charge an
                agreed fee to cover any reasonable Supplier's costs associated
                with such bar coding system. A joint meeting will be held
                between Supplier and Qwest within (***) of contract execution to
                further define these requirements and fees (if any).




                                     - 13 -
<PAGE>   18

9.      PAYMENT TERMS

        9.1     Subject to Section 12, Supplier shall invoice Qwest for Products
                upon shipment (and shall invoice Approved Affiliates for
                shipment to Approved Affiliates) and Qwest (or the Approved
                Affiliates) shall pay to Supplier the price of each shipment
                (including any prepaid transportation and/or insurance) within
                (***) from the date of (***). For all other Services (including
                Services provided to any Approved Affiliate), Supplier shall
                invoice Qwest (or the Approved Affiliate, as applicable) upon
                (***). Charges for any other amounts payable pursuant to this
                Agreement shall be paid by Qwest within (***). All payments
                shall be made in U.S. Dollars. The date of the payment shall
                be deemed to be the date (***).

        9.2     Qwest is not required to pay invoiced amounts disputed in good
                faith until such dispute is resolved; provided, however, Qwest
                shall pay that (***) unless it (***). Once the dispute is
                resolved, the invoice shall be paid within (***) following such
                resolution, or in the time frame set out in Section 9.1,
                whichever is greater.

        9.3     Credits owed to Qwest under this Agreement, may be applied
                against amounts owed to Supplier under this Agreement, or at
                Qwest's request, for amounts other than Management Discounts,
                retroactive discounts may be paid to Qwest within (***)
                following a request by Qwest.

        9.4     Payment shall not be considered Acceptance of any Products or
                Services (which Acceptance shall be as set forth in Section 12).
                Subject to Section 21, Supplier shall provide Products without
                interruption in the event of disputes concerning an invoice
                amount provided that the Parties are working together in good
                faith to resolve the dispute.


10.     PRODUCT REQUIREMENTS

        The following provision shall apply to all Products provided under this
        Agreement.

        10.1    Documentation.

                (a)     Supplier shall furnish to Qwest (***) in both (***)for
                        Qwest (***) for use in the operation and ongoing
                        maintenance of the Products. Supplier shall deliver
                        reasonable Documentation to allow Qwest to install and
                        use each ISU and Enhancement.

                                     - 14 -
<PAGE>   19

                (b)     Qwest may copy the Documentation subject to the rights
                        and restrictions in this Agreement and for Qwest's
                        internal use only. All such Documentation is to be
                        treated in accordance with the terms of this Agreement.
                        Updates to Documentation shall be provided at no charge
                        during the Warranty Period.

                (c)     The Documentation shall describe fully the proper
                        procedure for using the Products and provide sufficient
                        information to enable Qwest to operate and maintain the
                        Products.

        10.2    Equipment.

                (a)     Supplier shall make available to Qwest sufficient repair
                        and spare parts for each Product furnished under this
                        Agreement to keep such Product Operative for a period of
                        (***) from the date of last shipment of the Product.
                        (***) shall not exceed (***)from the (***). Supplier, at
                        its option and expense, may replace Products for which
                        repair parts are no longer available with functionally
                        equivalent Products provided that such products are
                        Network Compatible.

                (b)     Supplier shall provide Qwest with written notice of the
                        manufacturing discontinuance for any particular Product,
                        and, subject to subsection (a) above, shall furnish the
                        repair parts to Qwest at the (***) unless furnished
                        during the Warranty Period in which case a supply that
                        may be reasonably needed during the Warranty Period, and
                        (***) pursuant to the Warranty provided in Section 17,
                        shall be supplied (***).

                (c)     Supplier shall neither provide nor incorporate any
                        Product which adversely affects Form, Fit or Function,
                        Network Compatibility, interface or interchangeability
                        of Qwest's existing hardware or software environment
                        without the prior express written approval of Qwest.
                        Qwest shall notify Supplier if it becomes aware that a
                        Product is not Network Compatible.

                (d)     In the event of a (***), Supplier shall provide
                        immediate written notice to Qwest and shall proceed
                        promptly to make the necessary changes at (***).

                (e)     All changes must be Network Compatible.

                                     - 15 -
<PAGE>   20

        10.3    Substitutions and Modifications.

                Supplier shall give Qwest at least (***) advance written notice
                of any modification in the design or Specifications of the
                Products supplied hereunder. If any such modification, which
                affects the Form, Fit or Function of the Products (i) adversely
                affects the expected life, operation or performance of any
                Equipment or Software; (ii) causes Qwest to incur significant
                costs; (iii) prevents proper operation of equipment in the Qwest
                network that otherwise meets Specifications; or (iv) prevents
                any Product from meeting the applicable Specifications, Qwest
                shall have the right to (***).

                Supplier with written approval from Qwest, (***)to an (***).

        10.4    Incremental Software Updates.

                During any Warranty Period thereafter, Supplier shall offer to
                Qwest any ISUs contained in a Release or Version of the Software
                at (***) when they are made available to any of Supplier's other
                customers or upon a production of new Release or Version.
                Providing such ISUs shall not relieve Qwest of its obligation to
                (***). Qwest shall be responsible for installation of such ISUs
                in the network. Supplier shall make all Releases available to
                Qwest no later than it makes the same available to Supplier's
                other customers.

        10.5    Training.

                Supplier shall provide Supplier shall provide a training credit
                of (***) towards ASC training per (***) in orders placed by
                Qwest.

                The Courses are set forth in (***). The training will take place
                at a Supplier training location agreed to by the Parties, and
                will consist of materials developed and controlled by Supplier.
                All travel and living expenses for the training sessions shall
                be borne by Qwest. Training in addition to that described in
                this Section 10.5 shall be provided at the then current Supplier
                rates. A credit of (***) per (***) will be available


11.     CHANGES IN THE WORK

        11.1    If Qwest finds there is a need to request that Supplier perform
                services or provide products beyond the scope of this Agreement,
                then (i) Qwest shall submit a proposed amendment to the
                Schedules or this Agreement in writing and (ii) Supplier shall
                evaluate the impact of the proposed change considering cost,
                schedule and performance as well as any impact on the



                                     - 16 -
<PAGE>   21

                delivery of Products and Services to be provided hereunder and
                shall respond by providing Qwest with a formal proposal. The
                Parties may then further negotiate the proposed amendment or
                incorporate Supplier's proposal by written agreement as an
                amendment to this Agreement.

        11.2    If Supplier finds that there is a need for it to perform
                services or provide products beyond the scope of this Agreement,
                then Supplier shall submit a formal proposal detailing the
                proposed amendment in writing and evaluating the impact of the
                proposed amendment on cost, schedule and performance as well as
                any on the delivery of Products and Services to be provided
                hereunder. The Parties may then further negotiate the proposed
                amendment or incorporate Supplier's proposal by written
                agreement as an amendment to this Agreement.

        11.3    Any additional charges authorized by Qwest in writing, not
                contained in any Purchase Order or Schedule, shall reflect
                Supplier time and materials (and Supplier subcontractor time and
                materials) as stated in (***) or as otherwise agreed by the
                Parties in writing.

        11.4    Claims for Delay.

                (a)     If Supplier wishes to request an extension in the
                        delivery date for Products provided in a Purchase Order,
                        written request shall be given to Qwest at the time the
                        delay begins, or within (***) thereafter if the
                        resulting delay was not reasonably foreseeable. The
                        request shall state the circumstances of the occurrence,
                        the justification for the delay and extension of time,
                        and the estimated duration of the delay and extension
                        requested. Supplier shall also be obligated to do all in
                        its power to mitigate the adverse impact of such delay
                        at no additional cost to Qwest.

                (b)     Supplier agrees that it shall not request extensions of
                        time resulting from normal inclement weather




                                     - 17 -
<PAGE>   22

               (c) (***) shall be the sole remedy of Supplier for any delay
               caused by (***). Subject to Section 8.5, Supplier acknowledges
               (***) to be its sole remedy and agrees to make no claim for (***)
               of any sort for delay in the performance of this Agreement or any
               Purchase Order for any reason. Entitlement to (***)shall be
               subject to compliance with all notice and submission requirements
               imposed by the Agreement concerning such claims.


12.     ACCEPTANCE PERIOD; ACCEPTANCE

        12.1    Field Trial Test.

                All Products shall be subject to a test procedure as set forth
                in (***) hereto. In addition, for Products not certified by
                Qwest as Field Trial Accepted, Qwest agrees to conduct (***) and
                complete a Field Trial of such Products by (***), such Field
                Trial to be generally in accordance with (***), and as (***).
                Upon successful completion of the Field Trial Qwest will (***)
                in a form determined by Qwest, such Products as certified for
                "Expedited Acceptance." Upon receipt of such certification by
                Qwest, Qwest and the Approved Affiliates shall have the right to
                inspect and reject such Products for failure to be Network
                Compatible or other errors for a period of (***) from delivery
                (the "Expedited Inspection Period"). Subject to Section 12.5,
                such Products shall be deemed to have passed inspection and
                accepted after the expiration of the Expedited Inspection
                Period, unless Qwest or the Approved Affiliate notifies
                Supplier, during the Expedited Inspection Period, of a
                reasonable cause for rejection of the Products due to a failure
                (***).

                For all Products that have not been Field Trial Accepted by
                Qwest, each Approved Affiliate may perform Field Trial Tests.
                Upon successful completion of the Field Trial Test, such
                Approved Affiliate will (***) that for such Approved Affiliate,
                such Product is certified for Expedited Acceptance. Such
                Approved Affiliate shall then have the right to inspect and
                reject such Product for failure to be Network Compatible for the
                Expedited Inspection Period.

        12.2    Acceptance.

                For Products not certified for Expedited Acceptance, Qwest shall
                have the right to inspect and reject such Products for failure
                to be (***) for a period of (***) from scheduled delivery (the
                "Inspection Period"). Subject to Section 12.5, such Products
                shall be deemed to have passed inspection and accepted after the
                expiration of the Inspection Period, unless Qwest



                                     - 18 -
<PAGE>   23

                notifies Supplier, during the Inspection Period, of a reasonable
                cause for rejection of the Products due to a failure to be
                (***). Any subsequent order of a Product that has previously
                been accepted pursuant to this Section 12.2 (***).

        12.3    Failure of Acceptance.

                Qwest's payment obligations in Section 9 are contingent upon
                (***) in accordance with (***). If a Product fails to achieve
                acceptance as provided in (***), Qwest may return the Product,
                title to which shall pass to Supplier upon delivery to Supplier,
                and apply amounts paid for such Product, if any, and related
                Services to any unpaid Supplier invoice hereunder upon written
                notice to Supplier, or upon written demand by Qwest, Supplier
                shall repay such amounts, if paid by Qwest, to Qwest.

        12.4    New Products.

                In the event Supplier develops New Products Supplier will give
                Qwest (***) notice thereof, along with the expected
                Specifications therefor and pricing (***). Qwest may request
                that this Agreement be amended in order to make the terms of
                this Agreement applicable to the purchase by Qwest of New
                Products and the Parties shall negotiate in good faith the terms
                of such amendment, including (***), and the conduct by Qwest of
                a Field Trial for the New Product. Such Field Trial shall be
                substantially similar to the Field Trial described in (***)
                hereto. If the Field Trial for the New Product is successful,
                such New Products will be certified for Expedited Acceptance and
                the terms of this Agreement, as amended with respect to the New
                Product, shall apply to the purchase and sale of such new
                Products. New Products shall mean Products with material changes
                in previously applicable Specifications, which Specifications
                have not been approved by Qwest.

        12.5.   Commercial Use.

                Notwithstanding the foregoing, Products will be deemed accepted
                upon the full commercial deployment for use with network traffic
                by Qwest, irrespective of Expedited Acceptance status or the
                expiration of the Inspection Period or Expedited Inspection
                Period.


13.     SOFTWARE

        13.1    License Grant.

                                     - 19 -
<PAGE>   24

                Upon delivery of Software hereunder, Supplier grants to Qwest
                and its Affiliates who (***), (for the purposes of this Section,
                each a "Licensee") a nonexclusive, irrevocable, perpetual,
                worldwide license and right to use and make copies of the
                Software and the Intellectual Property Rights for which (***)
                for use solely with the applicable Products so long as Licensee
                uses such Products in accordance with this Agreement.
                Enhancements may be provided at a later date as set forth in
                (***). A "right to use" license under the same terms and
                conditions as set forth in this Section 13 for such Enhancement
                will be effective upon (***).

        13.2    Releases.

                Supplier may, from time to time, issue Releases to of the
                Software. As set forth in Section 1 (Definitions), Supplier may
                classify such Release as (i) an Enhancement, (ii) an ISU or
                (iii) both. During the Warranty Period and the term of any
                maintenance or support agreement, (***) shall (***). Qwest
                acknowledges that from time to time Enhancements may be
                contained in a Release that have not been licensed to Qwest.
                Qwest and Supplier shall agree in writing on the (***), in its
                (***). Notwithstanding the foregoing, ISUs and Enhancements
                shall not include the (***). Qwest shall be responsible for the
                installation of such Releases in the Network.

        13.3    Title.

                Subject to Section 13.5, Title to the Software described herein
                shall remain with Supplier, or with the various suppliers to
                Supplier whose software or software components are contained in
                the Software and whose rights of ownership are maintained
                through restrictive agreements with Supplier.

        13.4    Limitations of License Grant.

                (a)     The Software and Documentation are to be used only by
                        the Licensee, for its own business use, and only for the
                        intended use of the Software and Documentation (***) for
                        which (***).

                (b)     Licensed use is limited to the Software as delivered by
                        Supplier to Licensee and does not permit modification or
                        use of any modified form of the Software, except for
                        minor user modifications or customizations. Licensee may
                        not duplicate the Software, except to make a reasonable
                        number of backup copies of the Software for use in the
                        event of Product failure. If duplication (***).

                                     - 20 -
<PAGE>   25

                (c)     The Software and Documentation furnished hereunder are
                        the property of Supplier and are to be considered
                        Supplier's proprietary information. Licensee shall not
                        (***), before or after termination of this Agreement,
                        except as may be permitted in writing by Supplier.
                        Licensee shall immediately notify Supplier, in writing,
                        of any knowledge that any unlicensed party possesses the
                        Software or Documentation. Licensee shall safeguard said
                        Software with the same degree of care and diligence as
                        Licensee affords to its own similar property.

                (d)     Qwest acknowledges that Software may contain programs
                        that have been supplied by, and are proprietary to,
                        third party software vendors. The terms and conditions
                        of any such third party program licenses may be
                        different than the terms herein, and in such event,
                        (***) prior to delivery for such terms to be effective.
                        Supplier will extend to Qwest (***) under any such third
                        party Licenses.

        13.5    Derived Products and Derived Dependent Products.

                (a)     Any (i) Qwest (or Qwest Affiliate) (***) by Qwest (ii)
                        Qwest (or Qwest Affiliate) (***); (iii) Qwest (or Qwest
                        Affiliate) (***); and (iv) unless otherwise set forth in
                        a signed writing by the Parties referencing this
                        Section, any portion of a (***) or arrangement of the
                        (***)by Supplier (either with or without Qwest) after a
                        (***) therefore shall not be considered a derived
                        products and shall be distinct in ownership from that of
                        the Software as received by Qwest and shall be owned by
                        Qwest (and are hereby assigned to Qwest) (collectively,
                        the "Qwest Products"). The foregoing (iv) shall (***) or
                        otherwise (***) and does not result in any assignment to
                        Qwest of the Software apart from such portions of any
                        such configurations, applications or arrangements. Any
                        other configuration, application, or arrangement of the
                        Software, shall be considered a derivative work and
                        shall be the sole and exclusive property of Supplier;
                        provided, however, that Supplier may, at its discretion,
                        assign or license (***) or license not to be
                        unreasonably withheld.

                (b)     Any (***) which are (***) and are (***), shall be
                        considered a derived products to which Supplier retains
                        title and ownership and to which Licensee is granted an
                        exclusive perpetual, irrevocable, worldwide right to use
                        solely in its dependent form, and in conjunction with
                        the Software for so long as such Licensee uses such
                        Software in accordance with this Agreement.



                                     - 21 -
<PAGE>   26

                (c)     Supplier expressly prohibits, and Licensee agrees to
                        refrain from, any attempt by Licensee, Licensee's agent
                        or to permit any third party to disassemble, reverse
                        compile, reverse engineer, or, in any similar way,
                        expose the actual instruction sequences, internal logic,
                        protocols, algorithms or other intellectual property
                        represented within the Software, which Supplier
                        considers to be its proprietary information and trade
                        secret whether or not said intellectual property is
                        included in any patent or copyright. Notwithstanding any
                        other provision of this Agreement, any (***), such
                        effort by Licensee or any other party shall not be
                        assigned and shall be deemed the property of Supplier,
                        for which no right to use is granted to Licensee herein
                        and for which Supplier shall bear no obligations for
                        support.

        13.6    Software Maintenance and Support.

                (a)     Supplier shall provide Software technical support
                        services as provided in (***).

                (b)     Notice to Qwest of corrections or additions,
                        modifications or adjustments to the Software generally
                        available to other Supplier's customers with the same
                        Release shall be sent to a designated Qwest contact.
                        Supplier will, at its own discretion, make such
                        additions, modifications or adjustments to the Release
                        of the Software commonly known as the Current Release
                        except if such (***), in which case Qwest may (***)
                        obligations hereunder.

                (c)     Supplier agrees that at any point in time it will
                        support the then Current Release of the Software plus
                        the (***) immediately preceding Releases.

        13.7    (***) Delivery.

                (a)     Supplier shall keep and maintain a copy of Software
                        (***) and other Documentation relevant to the use and
                        maintenance of the Software licensed hereunder,
                        including without limitation the Current Release of the
                        Software. Should Supplier at a future date (i) declare
                        voluntary bankruptcy or be the subject of an involuntary
                        bankruptcy (***); or (ii) cease supporting the Products
                        or any other product incorporating such Software (***)
                        pursuant to this Agreement for a non-material amount of
                        time, then Supplier agrees and commits to Qwest that it
                        will promptly and (***) to the fullest extent permitted
                        by any third party intellectual owners, (***) which
                        Supplier has a legal right to sublicense, and hereby
                        grants to



                                     - 22 -
<PAGE>   27

                        Qwest a non-exclusive perpetual, irrevocable, worldwide
                        license to use, modify, (including creating derivative
                        works), and copy such (***) solely for the purpose of
                        supporting and maintaining the Products including
                        Software and only for so long as Licensee (***) Products
                        or Software (***).

                (b)     Supplier acknowledges that if a trustee in bankruptcy or
                        Supplier as a debtor in possession rejects this
                        Agreement, Qwest may elect to retain its rights under
                        this Subsection as provided in Section 365(n) of Title
                        11, United States Code (the "Bankruptcy Code"). In that
                        event, the license for the Software (***) will include
                        the following provisions:

                        (i)     Qwest has no further recourse with respect to
                                support in the areas to which the license
                                applies;

                        (ii)    Supplier will assume no obligations or
                                liabilities with respect to infringement
                                (related to the Supplier (***)), and/or Qwest's
                                inability to successfully support the Software
                                (***); and

                        (iii)   Supplier's then standard terms applicable to
                                confidentiality obligations and Supplier's
                                disclaimer of liabilities with respect to
                                Qwest's subsequent use (of the Software (***)).

        13.8    Documentation.

                In addition to the requirements of Section 10.1, Supplier shall
                provide (***). (***). Licensee may purchase (***) at the (***).
                Planning guides are available and will be delivered (***)with
                each and every Release delivered to Licensee.

        13.9    Transfer of License.

                (a)     Qwest may transfer, assign or sublicense (such
                        sublicense only to the extent (***) those rights (***)
                        to use the Products), any license granted by Supplier
                        hereunder, to any Affiliate, holding company, subsidiary
                        of holding company, subsidiary, associated company, or
                        successor in interest of Qwest or any person controlling
                        or controlled by any of the foregoing or to any person
                        directly or indirectly under common control with Qwest
                        (collectively, "License Transferee"), provided such
                        License Transferee (***).

                                     - 23 -
<PAGE>   28

               (b)    Qwest and any successor to Qwest's title in any Products
                      shall have the right without further consent of Supplier
                      to assign or sublicense (such sublicense only to the
                      extent necessary to grant those rights necessary to use
                      the Products), the License herein granted to any other
                      party who subsequently acquires the right to use the
                      applicable Products, provided that any such other party
                      prior to the transfer of the applicable Software (***) by
                      the (***).


14.     (***)

        14.1    (***)

        14.2    (***)


15.     INFRINGEMENT WARRANTY AND INDEMNITY

        15.1    Supplier warrants that it or its Affiliates are the owner of the
                Intellectual Property Rights of the Products, or, if the
                Products or other materials contain third party products or
                software, that Supplier has the full power and authority to
                deliver, convey and grant to Qwest the related license and other
                rights granted under this Agreement. Supplier further warrants
                that Supplier's provision of Services under this Agreement,
                grant of the licenses hereunder, and Qwest's use of the Products
                will not constitute a misappropriation of any trade secrets,
                infringement or misappropriation of any copyright or trademark
                or (***) any patent.

        15.2    Supplier shall defend or settle, at its expense, any threatened
                or actual claim, suit or proceeding made against Qwest that use
                of the Products infringes any patent, trademark, copyright,
                trade secret or other intellectual property right of a third
                party ("Infringement Claim"), and (***). In order for this
                indemnification to apply to a claim, Qwest shall give Supplier
                prompt notice following Qwest's knowledge of any such
                Infringement Claim, shall allow Supplier to control the defense
                of and settlement negotiations with regard to such claim,
                provided that Qwest (***) the settlement or compromise. The
                Parties shall provide reasonable cooperation and assistance in
                the defense of the Infringement Claim.

        15.3    If any Product furnished under this Agreement becomes, or in
                Qwest or Supplier's reasonable opinion is likely to become, the
                subject of any claim, suit, injunction or proceeding arising
                from or alleging infringement of, or in the event of any
                adjudication that such Product infringes on, any Intellectual
                Property Right, Supplier, (***), shall take the following
                actions in the listed order of preference:



                                     - 24 -
<PAGE>   29

                (a)     (***) to procure in a timely manner for Qwest and its
                        Affiliates (if applicable) the right to continue using
                        the Product (***); or if those efforts are unavailing;

                (b)     (***) to replace or modify the Product to make it
                        non-infringing; provided, however, that such
                        modification or replacement shall (***); or

                (c)     if (a) and (b) are commercially impracticable or would
                        cause the Products to fail to be (***), accept return of
                        the Product and refund Qwest (***). (***).

        15.4    Supplier shall have no liability in respect of any Infringement
                Claim based on the use of a Product to the extent that such
                claim (i) is based on a use of a Product by Qwest in a manner or
                for a purpose not contemplated by this Agreement; (ii) is based
                on a use of the Product by Qwest in combination with other
                non-Supplier products where such combination is (***), provided
                the Infringement Claim arises (***); or (iii) is based on a
                modification of the Product by Qwest where such modification has
                (***).

        15.5    This Section 15 establishes the entire rights and obligations of
                the Parties for claims of infringement of Intellectual Property
                Rights.


16.     KNOW HOW (***)

        Notwithstanding anything to the contrary contained in this Agreement,
        each Party shall be entitled (***) to use, disclose and sell any
        know-how retained in the minds of employees of such Party, expertise,
        techniques, approaches or concepts (the "Know-how") developed or
        acquired in the course of performing under this Agreement. The Parties
        agree that Know-how shall not include any Qwest, Supplier or third party
        (***), or any Confidential Information of the other Party. The foregoing
        shall not be construed as granting a license (***). The Parties
        recognize that New Technology may be developed during the Term. If any
        New Technology is deemed by the Party that created it to be deserving of
        intellectual property protection, then that Party is responsible for
        taking steps to protect any interests it may have in such New Technology
        and may refuse to disclose such New Technology during its pursuit of
        (***) in the same.


17.     WARRANTY

        17.1    (a)     Supplier warrants that the Products supplied hereunder
                        will befree from (***) defects in design, workmanship
                        and material and shall (***) conform to its
                        Specifications for (***) from the date of



                                     - 25 -
<PAGE>   30

                        shipment stamped on the Product or, if the date of
                        shipment is not marked on the Product, (***) from the
                        date of manufacture ("Warranty Period"), or if the date
                        of shipment is not marked on the Product, (***) from the
                        date of manufacture.

                (b)     The foregoing warranty shall not apply to the extent
                        that (i) the (***) is caused by the Product having been
                        altered or repaired by any party other than Supplier
                        without Supplier's prior, written consent; (ii) the
                        (***) results from Qwest's (***); or (iii) the Product
                        having been damaged by (***). This foregoing Product
                        warranty does not apply to items normally consumed in
                        operation, such as, but not limited to, lamps and fuses.
                        If a (***) occurs, Qwest shall give Supplier a
                        reasonable opportunity to (***), as set forth in (***),
                        before exercising any other rights or remedies it may
                        have under this Agreement.

                (d)     Supplier shall provide technical support for a Product
                        performed by qualified and competent personnel for a
                        period of (***) after Acceptance of the Product as set
                        forth in (***).

        17.2    Supplier warrants that the (***) and any media used to
                distribute it does not contain any computer instructions,
                circuitry, routines or other technological means ("Harmful
                Code") whose purpose is to disrupt, damage or interfere with
                Qwest's use of its computer and telecommunications facilities
                for their commercial, test or research and development purposes.
                Supplier shall indemnify Qwest and hold Qwest harmless from and
                against any and all claims, losses, costs, liabilities, damages
                and/or expenses, including reasonable attorneys fees, arising
                from the presence of Harmful Code in or with the Software or
                contained on media delivered by Supplier.

        17.3    Supplier shall perform all Services required under this
                Agreement including without limitation, customization services,
                implementation, maintenance services and training services in a
                (***) of any development tools used in providing its Services.
                With Qwest's prior written consent, Supplier may perform its
                (***) hereunder through an agent.

        17.4    Supplier warrants during the Warranty Period that the Products
                provided hereunder shall be able to accurately process data
                (including without limitation, calculating, compiling and
                sequencing date data) from, into and between the twentieth and
                twenty-first centuries, including leap year calculations, and
                will create, store, process and exchange (input and output)
                information related to or including dates on or after January 1,
                2000, without error or omissions ("Year 2000 Compliant").



                                     - 26 -
<PAGE>   31

        17.5    The Warranty Period for any replacement Product provided by
                Supplier under this Agreement shall be the greater of (***); or
                (ii) an additional Warranty Period of (***) from the date of
                Acceptance of the replacement Product by Qwest.

        17.6    Upon expiration of the applicable Warranty Period for Equipment
                furnished hereunder, repair and replacement service for such
                Equipment shall be available to Qwest from Supplier in
                accordance with (***).

        17.7    During the Warranty Period for a Product, Supplier shall provide
                warranty support services performed by (***) personnel as set
                forth in ScheduleG. Supplier shall deliver to Qwest and keep
                current a list of persons and telephone numbers ("Calling List")
                for Qwest to contact in order to obtain answers to questions
                arising, or assistance in solving problems or Nonconformities
                occurring, during Qwest's use of any of the Products. The
                Calling List shall include (i) the first person to contact if a
                question arises or problem occurs, and (ii) the persons in
                successively more responsible or qualified positions to provide
                the answer or assistance desired. If Supplier does not respond
                promptly to any request by Qwest for telephone assistance, then
                Qwest may attempt to contact the next more responsible or
                qualified person on the Calling List until contact is made and a
                designated person responds to the call.

        17.8    Except for a letter received from Nortel alleging that
                Supplier's products infringe one of Nortel's patents relating to
                inverse multiplexing over ATM, which allegation Supplier
                believes to be without merit, Supplier represents and warrants
                that as of the Effective Date of this Agreement, the Supplier
                has not received written notice of any pending lawsuits, claims,
                disputes or actions that it reasonably considers significant (i)
                alleging that the Products infringe or misappropriate any
                Intellectual Property Rights, or (ii) adversely affecting the
                Products or Supplier's ability to undertake and perform its
                obligations under this Agreement. As set forth in Section 15.2,
                Supplier shall indemnify Qwest against any and all losses based
                on the Nortel claim.17.10 After Qwest reports a suspected
                Nonconformity, Supplier shall provide a correction or work
                around or repair part to restore the Product (including the
                entire System) to Operative condition as soon as reasonably
                possible, but in any case in conformance with the designated
                repair times in the Specifications in the applicable Schedules
                to this Agreement.

        17.10   Any Release made available to any of Supplier's customers within
                the Warranty Period for any Product that correct (***) shall be
                provided to Qwest at no additional charge. Such Release shall be
                in compliance with the (***) for any of the Products under this
                Agreement.



                                     - 27 -
<PAGE>   32

        17.11   Supplier warrants that the Products: (i) will meet all
                applicable standards including, but not limited to, (***); (ii)
                will provide the functionality described in the Specifications;
                (iii) will conform to the current environmental specifications
                set forth in the (***); and (iv) will be (***).

        17.12   THE EXPRESS WARRANTIES IN THIS AGREEMENT INCLUDING THE SCHEDULES
                ATTACHED HERETO ARE IN LIEU OF ANY OTHER WARRANTY, WHETHER
                EXPRESS, IMPLIED OR STATUTORY, WITH RESPECT TO THE PRODUCT TO BE
                SUPPLIED UNDER THIS AGREEMENT. EXCEPT AS EXPRESSLY SET FORTH
                HEREIN, SUPPLIER SPECIFICALLY DISCLAIMS THE IMPLIED WARRANTIES
                OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE,
                NON-INFRINGEMENT OF THIRD PARTY RIGHTS AND THOSE ARISING FROM A
                COURSE OF DEALING OR USAGE OF TRADE. SUPPLIER NEITHER ASSUMES
                NOR AUTHORIZES ANY PERSON TO ASSUME FOR IT ANY OTHER LIABILITY.
                THE WARRANTIES EXPRESSED HEREIN SHALL NOT BE (***) EXCEPT AS
                SUCH PRODUCTS OR OTHER RIGHTS ARE (***) OR (***) PURSUANT TO THE
                TERMS AND CONDITIONS OF THIS AGREEMENT.

18.     GENERAL INDEMNITY

        (***) shall indemnify and hold harmless (***) from any claim or damages
        due to the personal injury or death of any individual and against any
        reasonably foreseeable loss, damage, liability, cost or expense
        (including attorneys' fees) (a) which may be incurred on account of any
        suit, claim, judgment, demand, or threat thereof, arising out of or
        caused by a willful or grossly negligent act or omission or an
        intentional act of misconduct of the (***), its agents, employees or
        subcontractors.


19.     LIMITATION OF LIABILITY

        NEITHER PARTY SHALL BE LIABLE TO THE OTHER (OR ANYONE CLAIMING UNDER OR
        THROUGH THE OTHER) FOR ANY SPECIAL, INDIRECT, CONSEQUENTIAL, PUNITIVE OR
        EXEMPLARY DAMAGES ARISING FROM OR RELATED TO THIS AGREEMENT, INCLUDING,
        BUT NOT LIMITED TO, LOST PROFITS OR OTHER ECONOMIC ADVANTAGE, EVEN IF
        THE PARTIES HAVE KNOWLEDGE OF THE POSSIBILITY OF SUCH DAMAGES. PROVIDED,
        HOWEVER, THAT IF THE LAW OF ANY JURISDICTION APPLICABLE TO THIS
        AGREEMENT DOES NOT PERMIT SUCH DAMAGES TO BE COMPLETELY DISCLAIMED, THIS
        CLAUSE SHALL BE INTEREPRETED AS NECESSARY TO GIVE SUPPLIER THE



                                     - 28 -
<PAGE>   33

        FULL BENEFIT OF ANY DISCLAIMER OR LIMITATION OF SAID DAMAGES AS
        PERMITTED UNDER SUCH LAW. THE FOREGOING LIMITATION SHALL NOT APPLY IN
        THE EVENT OF LIABILITY ARISING FROM: (***) ARISING OUT OF OR IN
        CONNECTION WITH THIS AGREEMENT.


 20.    CONFIDENTIALITY

        20.1    This Agreement and all information marked as confidential and
                disclosed by either Party (the "Disclosing Party") to the other
                (the "Recipient"), or information of a confidential nature which
                is disclosed orally and for which a written summary is provided
                to the other Party within (***) of disclosure (provided that no
                written summary shall be required for confidential information
                of a (***) which is disclosed orally between the Parties' (***)
                which such personnel should reasonably understand to be
                confidential) shall be "Confidential Information". Confidential
                Information constitutes a valuable asset of and is proprietary
                to the Party disclosing or originally possessing it. Supplier
                acknowledges that Qwest keeps its customers' records strictly
                confidential. Supplier and its Representatives shall keep
                strictly confidential any Qwest customer records, whether or not
                they are marked as confidential. Neither Party shall willfully
                disclose Confidential Information or knowingly permit its
                Representatives to disclose Confidential Information to any
                person other than persons, including its Representatives, having
                a specific need to know in performance of the work. Each Party
                shall take reasonable care to insure fulfillment of this
                obligation, including instructing its Representatives not to
                sell, lease, assign, transfer, use outside their scope of
                employment or reveal any Confidential Information or Qwest
                customer records without prior written consent of the other
                Party. Recipient shall use the Disclosing Party's Confidential
                Information only for purposes of exercising its rights or
                fulfilling its obligations under this Agreement and shall
                disclose Confidential Information only to those (***). Recipient
                shall return or destroy the Confidential Information (including
                all copies) when no longer needed or when requested to do so by
                the Disclosing Party Each Recipient shall take (***) to insure
                fulfillment of this obligation, including instructing its
                Representatives not to sell, lease, assign, transfer, use
                outside their scope of employment or reveal any Confidential
                Information, including but not limited to customer records,
                without prior written consent of the Disclosing Party.

        20.2    If a subpoena or other legal process in any way concerning
                Confidential Information is served upon Recipient, the Recipient
                shall notify the Disclosing Party promptly, and the Recipient
                shall cooperate with the



                                     - 29 -
<PAGE>   34

                Disclosing Party, at the latter's expense, in any lawful effort
                to contest the validity of such subpoena or other legal process.

        20.3    Notwithstanding the foregoing, if either Party is required by
                law or governmental regulation by compulsory judicial or
                administrative process to make any disclosure, including but not
                limited to those made in any registration statement, report or
                other document filed with the U.S. Securities and Exchange
                Commission or any other governmental agency, such disclosure
                will not be deemed to violate the terms of this Section,
                provided the Recipient promptly notifies the Disclosing Party of
                such disclosure and (***) to protect the intent of the Parties
                to restrict disclosure of all Confidential Information and the
                terms of this Agreement, including but not limited to seeking
                confidential treatment of all such information in administrative
                filings. In addition, if the Recipient's efforts to seek
                confidential treatment or other protective measures for such
                information are not successful, such party may only make such
                disclosure after (i) providing written notice of the same to the
                disclosing party and (ii) (***) the Disclosing Party to take
                measures to secure the confidential treatment of the
                information.

        20.4    Qwest may disclose the (***) to its contractors who have a need
                to know for purposes of exercising rights related to this
                Agreement, provided that such contractors have agreed in writing
                to observe in substance the obligations of Qwest set forth in
                this Section.

        20.5    The obligations of confidentiality in this Section shall not
                apply to any information which a Party has in its possession
                when disclosed to it by the Disclosing Party, information which
                a Party independently develops, information which is or becomes
                known to the public other than by breach of this Agreement or
                information rightfully received by a Party from a third party
                without the obligation of confidentiality.

        20.6    A Party shall not (***).




                                     - 30 -
<PAGE>   35

21.     TERMINATION, SURVIVAL

        21.1    Bankruptcy. Either Party may terminate the Agreement if the
                other Party shall: (a) file a voluntary petition under any
                bankruptcy or insolvency law, or file a voluntary petition under
                the reorganization or arrangement provisions of any law of any
                jurisdiction, or have proceedings under any such laws instituted
                against it which are not terminated within (***) of such
                commencement; (b) becomes insolvent, bankrupt, or admit in
                writing of its inability to pay all debts as they mature or make
                a general assignment for the benefit of or enter into any
                composition or arrangement with creditors; or (c) authorize,
                apply for, or consent to the appointment of a receiver, trustee,
                or liquidator of all or a substantial part of its assets, or has
                proceedings seeking such appointment commenced against it which
                are not terminated within (***) of such commencement.

        21.2    Change of Control. If, during the Term of this Agreement, an
                entity, person or successor acquires (***) of Qwest's voting
                securities or all or substantially all of its assets whether by
                merger, consolidation, reorganization or sale of assets then the
                acquiring entity, person or successor shall have the right to
                terminate this Agreement or a part thereof upon (***) written
                notice, and Qwest shall have no further obligations under this
                Agreement except for (i) payment due for any Products retained
                by Qwest for which Supplier has not received payment; (ii)
                payment due for any Services completed by Supplier for which
                Supplier has not received payment and (iii) payment of (***) of
                the difference between the (***) amount (as such amount exists
                as of the date of termination) and the amount of payments
                received by Supplier.

        21.3    (***) of Acquired Entities. If, during the Term of this
                Agreement, Qwest or any of its Affiliates acquire a controlling
                interest in or substantially all the assets of an entity
                ("Acquired Entity") that has an agreement with Supplier for
                products, services and/or software with remaining purchase
                commitments, (***).

        21.4    Termination for Cause. Either party may terminate or suspend
                this Agreement upon (***) of this Agreement by the other after
                providing written notice to the other Party (***). Upon the
                breaching Party's receipt of the other Party's notice, the
                breaching Party shall have (***) to cure the breach. If the
                breaching Party is unable to cure such breach within such (***)
                period, the other Party (***).



                                     - 31 -
<PAGE>   36

        21.5    Survival. All provisions of this Agreement which by their nature
                must survive termination in order to achieve the fundamental
                purposes of this Agreement shall survive any termination of this
                Agreement, including but not limited to the following Sections:
                2 (Scope), 9 (Payment Terms), 13 (Software), 15 (Infringement
                Warranty and Indemnity), 16 (Warranty), 17 (General Indemnity),
                18 (Limitation of Liability), 19 (Confidentiality), 20
                (Termination, Survival), 30 (Severability) and 32 (Choice of
                Law).


 22.    FORCE MAJEURE

        22.1    Except to the extent of normal inclement weather, which shall be
                built into any schedule, neither Party will be liable for any
                delay or failure to perform - hereunder due to acts of God, acts
                of any government, war, riot, fire, flood, accident, or embargo,
                typhoon, earthquake, natural disasters, industry-wide labor
                disputes, industry-wide materials shortage, or any other event
                beyond the reasonable control of the party that is unable to
                perform (each an event of "Force Majeure"). In the event of such
                delay or failure to perform, the Party prevented from performing
                its obligations under this Agreement shall inform the other
                Party as soon as possible and the schedules shall be extended
                for such additional period of time as is determined to be
                equitable by the Parties. With respect to labor difficulties, a
                Party shall not be obligated to accede to any demands being made
                by employees or other personnel.

        22.2    The Party prevented from performing its obligation shall inform
                the other Party as soon as possible after the Force Majeure
                event ends. If an event of Force Majeure last for longer than
                (***) the Parties shall attempt in good faith to determine a
                time frame for further performance of this Agreement through
                consultation. If the Parties cannot solve the problem of further
                performance within an additional (***), either Party may
                terminate this Agreement without penalty.


23.     ASSIGNMENT

        23.1    Subject to Section 13.9, except as provided below, neither Party
                shall assign any of its rights nor delegate any of its
                obligations under this Agreement (***). Any prohibited
                assignment or delegation shall be null and void.

        23.2    Qwest may assign this Agreement without prior approval to any
                company or Entity controlling, controlled by or under common
                Control of Qwest or



                                     - 32 -
<PAGE>   37

                its Affiliates which assignee is (***) hereunder. In addition
                and notwithstanding the foregoing, Qwest may assign this
                Agreement without the approval of Supplier to any successor in
                interest resulting from a merger, acquisition, reorganization or
                transfer of all or substantially all of Qwest's business with or
                to a successor.


24.     JOINT WORK PRODUCT

         The Parties, who have both been represented by legal counsel, have
        jointly participated in negotiating and drafting this Agreement,
        including its Schedules and any attachments. In the event an ambiguity
        or question of intent or interpretation arises, this Agreement shall be
        construed as if jointly drafted by the Parties and no presumption,
        inference or burden of proof shall arise favoring or disfavoring a Party
        by virtue of authorship of any or all of the Agreement provisions.


25.     DISPUTES

        25.1    The Parties shall work together and attempt to resolve by good
                faith and diligent negotiation any dispute, controversy or claim
                between them arising out of or relating to any contract
                document, or the breach, termination or invalidity thereof (a
                "Dispute"). The Parties shall work together in good faith to
                informally resolve the dispute internally by escalating it as
                necessary to progressively higher levels of management.
                Following such internal process, if the dispute has not been
                resolved within (***) after formal initiation of the dispute
                process, either Party may initiate arbitration as provided for
                below.

        25.2    Following the procedure discussed in Section 25.1 above, binding
                arbitration shall be used to resolve any Dispute. Such
                arbitration shall be conducted in accordance with the then
                current Commercial Arbitration Rules of the American Arbitration
                Association ("AAA Rules") by (***). Within (***) of a notice of
                arbitration, each Party shall appoint one arbitrator and the
                arbitrators appointed shall together appoint a third. Once the
                third arbitrator has officially accepted such appointment, the
                arbitrators shall be deemed a panel (hereinafter, the
                "Impanelment").

        25.3    The Federal Arbitration Act, 9 U.S.C. Secs. 1-16 shall govern
                the arbitrability of all Disputes. The arbitration proceedings
                shall be English and the place of arbitration shall be (***).
                The construction and interpretation of this Agreement shall be
                governed by the laws of the (***) without reference to its
                conflicts of law rules, or rules of statutory



                                     - 33 -
<PAGE>   38

                arbitration. Arbitral awards under this Section 25 shall be
                final and binding, and shall be enforceable in any court having
                jurisdiction.

        25.4    (a) Nothing in this Section will prevent any Party from applying
                to any court of competent jurisdiction for preliminary or
                interim relief in a judicial proceeding if such relief from a
                court is necessary to preserve the status quo pending resolution
                or to prevent serious and irreparable injury to that Party
                pending resolution of the Dispute through arbitration, or to
                compel arbitration in accordance with this Section.

                (b) For purposes of this Section each Party consents to the
                exclusive jurisdiction and venue of the courts of the state and
                federal courts of (***).

                (c) Each party shall bear its own costs and legal fees
                associated with such arbitration. (***).


26.     RELATIONSHIP OF THE PARTIES

        26.1    The Parties are independent contractors. Nothing in this
                Agreement or in the activities contemplated by the Parties
                pursuant to this Agreement shall be deemed to create an agency,
                partnership, employment or joint venture relationship between
                the Parties. Each Party shall be deemed to be acting solely on
                its own behalf and, except as expressly stated, has no authority
                to pledge the credit of, or incur obligations or perform any
                acts or make any statements on behalf of, the other Party.
                Neither Party shall represent to any person or permit any person
                to act upon the belief that it has any such authority from the
                other Party. Neither Party's officers or employees, agents or
                contractors shall be deemed officers, employees, agents or
                contractors of the other Party for any purpose.

        26.2    Supplier represents and warrants that Supplier qualifies as an
                independent contractor under the provisions of the Internal
                Revenue Code's common law rules enacted as part of Section 1706
                of the 1986 Tax Reform Act, and as such Supplier is filing all
                required forms and necessary payments appropriate to Supplier's
                tax status. In the event Supplier's independent status is denied
                or changed and Supplier is declared to have "common law" status
                with respect to work performed for Qwest, Supplier agrees to
                indemnify, defend and hold Qwest and its Affiliates harmless
                from all costs, including legal fees, which Qwest may incur as a
                result of such change in status.




                                     - 34 -
<PAGE>   39

27.     AMENDMENT

        No changes, amendments or modifications of any of the terms or
        conditions of this Agreement shall be valid unless made by an instrument
        in writing signed by both Parties. None of the terms or conditions of
        this Agreement shall be modified, amended or altered by or through a
        Purchase Order. Each Party shall designate by written notice to the
        other Party the individual who has the authority to amend this
        Agreement. Each Qwest Affiliate that becomes a party to this Agreement
        agrees that any changes, amendments or modifications of any of the terms
        or conditions of this Agreement approved by Qwest is binding upon such
        Affiliate.


28.     COMPLIANCE WITH LAWS

        The Parties shall comply with all applicable federal, state and local
        laws, regulations and ordinances as they relate to this Agreement and
        the Software, including, but not limited to, the regulations of the
        United States Government, the provisions of Executive Order 11246 (as
        amended) of the President of the United States on Equal Employment
        Opportunity and the rules and regulations issued pursuant thereto, which
        are incorporated in this Agreement by this reference as if set forth in
        full. Supplier and the Products shall comply with (***) under the terms
        and conditions set forth in this Agreement.


29.     CONSTRUCTION/HEADINGS

        All Schedules and attachments, as supplemented and amended, to this
        Agreement or to be attached to this Agreement are made a part of it as
        if fully included in the text of this Agreement. References to any law,
        legislative act, rule or regulation shall mean references to such law,
        legislative act, rule or regulation in changed or supplemented form or
        to a newly adopted law, legislative act, rule or regulation replacing a
        previous law, legislative act, rule or regulation. All defined terms
        used in the Agreement shall have the same meanings ascribed to them when
        used in the Schedules, attachments and Purchase Orders, unless otherwise
        specified therein. The terms "including" or "includes" shall always be
        construed as meaning respectively "including without limitation" or
        "includes without limitation". The title, captions and headings used in
        this Agreement are strictly for convenience of reference only and shall
        not be used in the interpretation, construction, amplification or
        limitation of any of the content of this Agreement. Whenever the
        singular is used herein, the same shall include the plural where
        appropriate, and when the plural is used herein, the same shall include
        the singular where appropriate.




                                     - 35 -
<PAGE>   40

30.     NO WAIVER

        No delay, failure or waiver of either Party's exercise or partial
        exercise of any right or remedy under this Agreement shall operate to
        limit, impair, preclude, cancel, waive or otherwise affect such right or
        remedy.

31.     SEVERABILITY

        If any provision of this Agreement is held invalid, illegal or
        unenforceable, the validity, legality or enforceability of the remaining
        provisions shall in no way be affected or impaired thereby.

32.     COUNTERPARTS

        This Agreement may be executed by the Parties in one or more
        counterparts, and each of which when so executed shall be an original,
        but all such counterparts shall constitute one and the same instrument.

33.     CHOICE OF LAW

        This Agreement is entered into in and shall be governed by the internal
        laws and not the laws regarding conflicts of laws of the (***). The
        (***) shall be (***). Each Party agrees to waive its right to a jury
        trial in any action commenced hereunder.

34.     REMEDIES

        The remedies under this Agreement shall be cumulative and not exclusive,
        and the election of one remedy shall not preclude pursuit of other
        remedies generally available under the governing law.

35.     IMMIGRATION REFORM AND CONTROL ACT

        Supplier warrants, represents, covenants and agrees that it will not
        assign to perform any efforts under this Agreement any individual who is
        an unauthorized alien under the Immigration Reform and Control Act of
        1986 or its implementing regulations. Supplier shall indemnify and hold
        harmless Qwest, its parent, subsidiaries and affiliated companies from
        and against (***). In the event any Supplier Personnel or contractor
        working under this Agreement, or other individuals providing work to
        Qwest on behalf of Supplier under this Agreement, are discovered to be
        unauthorized aliens, Supplier will (***) remove such individuals from
        performing Work and replace such individuals with individuals



                                     - 36 -
<PAGE>   41

        who are not unauthorized aliens. Supplier shall indemnify and hold
        harmless Qwest, its parent, subsidiaries and affiliated companies from
        and against any and all liabilities, damages, losses, claims or expenses
        (including attorneys' fees) (***).


36.     IMPORT/EXPORT

        Qwest hereby covenants that no commodities or technical data, including
        computer software, or other technology agreed to be sold or otherwise
        transferred under this Agreement will be sold, leased, delivered,
        transferred or conveyed to any person in any country except in strict
        compliance with all export and import laws, regulations, executive
        orders or decrees of the United States Government or any agencies
        thereof and the government of any other country, or any agencies
        thereof, with jurisdiction over such transaction. Qwest shall, solely at
        its own expense, obtain all required export and import licenses,
        permits, approval, certificates and verifications before shipment of any
        Products.


37.     PUBLICITY

        Neither Party shall, without the prior written approval of the other
        Party, publicly disclose in any press release, filing, brochure or
        document any information pertaining to this Agreement.


38.     NOTICES

        38.1    In addition to those instances identified throughout this
                Agreement that require notices to particular individuals via
                particular means for particular purposes, all notices, requests,
                demands, or consents required or permitted hereunder, other than
                routine operational communication, shall be in writing and shall
                be delivered, sent by facsimile transmission or overnight
                courier, or sent by certified or registered mail to the
                respective Party at the addresses set forth below or at such
                other address as shall have been given to the other Party in
                writing for the purposes of this Section and Agreement. Such
                notices and other communications shall be deemed effective upon
                the earliest to occur of (i) actual delivery of confirmed
                facsimile or electronic transmission; (ii) three (3) postal
                delivery days after the date of mailing by certified or
                registered mail, return receipt requested, postage prepaid;
                (iii) one (1) business day after dispatch via an express courier
                with a reliable system for tracking delivery; (iv) actual
                delivery by hand.

                (a)     If to Supplier :

                                     - 37 -
<PAGE>   42

                Advanced Switching Communications, Inc.
                8330 Boone Boulevard
                Fifth Floor
                Vienna, Virginia 22182

                        If to Qwest:

                Qwest Communications Corporation
                555 17th Street
                Denver, Colorado 80202
                Attention: (***)


                38.2 A Party may from time to time change its address for
                notification purposes by giving the other Party prior written
                notice of the new address and the date upon which it will
                become effective, in accordance with the manner set forth in
                this Section.

39.     INSURANCE REQUIREMENTS

        39.1    During the Term, Supplier and any of its subcontractors shall
                maintain insurance of the kinds and in the amounts specified
                below with insurers of recognized responsibility, whose policies
                are valid in the states where the work is being performed.

        39.2    In accordance with the above, Supplier and any subcontractors
                shall maintain the following insurance coverage:

                (a)     Comprehensive general liability insurance.

                (b)     Commercial general liability insurance with a combined
                        single limit for bodily injury and property damage of
                        (***) each occurrence and General and Products Liability
                        aggregates of (***) each, covering all operations and/or
                        work performed under this Agreement.

                (c)     Business automobile liability insurance.

                (d)     Business automobile liability with a combined single
                        limit for bodily injury and property damage of (***)
                        each occurrence to include coverage for all owned,
                        non-owned, and hired vehicles.

                (e)     Worker's compensation and employers' liability
                        insurance.

                                     - 38 -
<PAGE>   43

                (f)     Worker's compensation insurance complying with the law
                        of the State or States of operation, whether or not such
                        coverage is required by law, and employer's liability
                        insurance with limits of (***) each employee and (***)
                        disease policy limit.

        39.3    Certificates of such insurance shall be submitted to Qwest
                naming Qwest as an additional insured with respect to Sections
                39.2(a) and 39.2(b) prior to the start of any Work associated
                with this Agreement. These certificates shall provide that there
                will be no termination or non-renewal of such coverage without
                thirty (30) days prior written notice to Qwest, in which case
                Supplier shall still maintain insurance and which may require
                certificate, and in no case where this Agreement is still in
                effect.

        39.4    Supplier shall require each subcontractor to provide and
                maintain at all times during the term of this Agreement
                insurance equivalent to that which is required of Supplier. Any
                subcontractor and any subcontractors' carriers shall waive all
                right to recovery against Qwest for any injuries to persons or
                damage to property in the execution of Work performed under this
                Agreement, exclusive of such liability resulting from Qwest's
                negligence or intentional misconduct and within the limits of
                any applicable laws.

        39.5    Should Supplier at any time neglect or refuse to provide the
                insurance required, or should such insurance be canceled or
                non-renewed, Qwest shall have the right to purchase such
                insurance, and the cost shall be billed to Supplier. In
                addition, should Supplier at any time neglect or refuse to pay
                the necessary premium, Qwest shall have the right to deduct this
                amount from monies due Supplier.


40.     ORDER OF PRECEDENCE

        In the event of an inconsistency between the terms and conditions of the
        Agreement and the Schedules attached hereto, the Agreement shall
        control.


41.     ENTIRE AGREEMENT

        41.1    This Agreement, together with any other instrument, agreement or
                document attached or referred to, which are incorporated by this
                reference as though set forth in full, embodies the final, full
                and exclusive statement of the agreement between Qwest and
                Supplier, as it relates to the subject matter hereof. Neither
                Party shall be bound by or liable to the other Party for any
                representation, promise or inducement made by any agent or
                person in their employ relating to subject matter which is not
                embodied in this Agreement.



                                     - 39 -
<PAGE>   44

        41.2    The terms of this Agreement shall prevail over all preprinted
                forms, including Purchase Orders, software shrink wrap licenses
                and invoices, as any terms and conditions on such preprinted
                forms shall be null and void unless otherwise agreed to in
                writing by both Parties.

                                      * * *

IN WITNESS WHEREOF, the Parties hereto have caused this Agreement to be duly
executed as of the Effective Date, such Parties acting by their officers, being
thereunto duly authorized.

Advanced Switching Communications, Inc.    Qwest Communications Corporation

<TABLE>
<S>                                     <C>
By: /s/ HARRY J. D'ANDREA               By: /s/ RICHARD SHAWL
   -----------------------------           -----------------------------

Title: Chief Financial Officer          Title: Vice President Central Office Engineering
     ---------------------------             ---------------------------------------------

Date: October 3, 2000                   Date: October 3, 2000
     ---------------------------             ---------------------------
</TABLE>





                                     - 40 -

<PAGE>   45
NOTE: REDACTED PORTIONS HAVE BEEN MARKED WITH (***). THE REDACTED PORTIONS ARE
SUBJECT TO A REQUEST FOR CONFIDENTIAL TREATMENT THAT HAS BEEN FILED WITH THE
SECURITIES AND EXCHANGE COMMISSION.

                                   SCHEDULE A


                                QWEST AFFILIATES

(***)








<PAGE>   46

NOTE: REDACTED PORTIONS HAVE BEEN MARKED WITH (***). THE REDACTED PORTIONS ARE
SUBJECT TO A REQUEST FOR CONFIDENTIAL TREATMENT THAT HAS BEEN FILED WITH THE
SECURITIES AND EXCHANGE COMMISSION.

                                   SCHEDULE B



                                     (***)

<PAGE>   47

NOTE: REDACTED PORTIONS HAVE BEEN MARKED WITH (***). THE REDACTED PORTIONS ARE
SUBJECT TO A REQUEST FOR CONFIDENTIAL TREATMENT THAT HAS BEEN FILED WITH THE
SECURITIES AND EXCHANGE COMMISSION.

<PAGE>   48


NOTE: REDACTED PORTIONS HAVE BEEN MARKED WITH (***). THE REDACTED PORTIONS ARE
SUBJECT TO A REQUEST FOR CONFIDENTIAL TREATMENT THAT HAS BEEN FILED WITH THE
SECURITIES AND EXCHANGE COMMISSION.

                                   SCHEDULE C

(***)



<PAGE>   49


NOTE: REDACTED PORTIONS HAVE BEEN MARKED WITH (***). THE REDACTED PORTIONS ARE
SUBJECT TO A REQUEST FOR CONFIDENTIAL TREATMENT THAT HAS BEEN FILED WITH THE
SECURITIES AND EXCHANGE COMMISSION.

                                   SCHEDULE D

(***)



<PAGE>   50
NOTE: REDACTED PORTIONS HAVE BEEN MARKED WITH (***). THE REDACTED PORTIONS ARE
SUBJECT TO A REQUEST FOR CONFIDENTIAL TREATMENT THAT HAS BEEN FILED WITH THE
SECURITIES AND EXCHANGE COMMISSION.

                                   SCHEDULE E

(***)



<PAGE>   51

NOTE: REDACTED PORTIONS HAVE BEEN MARKED WITH (***). THE REDACTED PORTIONS ARE
SUBJECT TO A REQUEST FOR CONFIDENTIAL TREATMENT THAT HAS BEEN FILED WITH THE
SECURITIES AND EXCHANGE COMMISSION.

                                   SCHEDULE F

(***)



<PAGE>   52
NOTE: REDACTED PORTIONS HAVE BEEN MARKED WITH (***). THE REDACTED PORTIONS ARE
SUBJECT TO A REQUEST FOR CONFIDENTIAL TREATMENT THAT HAS BEEN FILED WITH THE
SECURITIES AND EXCHANGE COMMISSION.

                                   SCHEDULE G

(***)



<PAGE>   53
NOTE: REDACTED PORTIONS HAVE BEEN MARKED WITH (***). THE REDACTED PORTIONS ARE
SUBJECT TO A REQUEST FOR CONFIDENTIAL TREATMENT THAT HAS BEEN FILED WITH THE
SECURITIES AND EXCHANGE COMMISSION.

                                   SCHEDULE H


                               THIRD PARTY ITEMS

ASC warrants and represents to Qwest Communications Corporation that Third Party
Items and Third Party Warranties do not exist under the terms of this Agreement.


<PAGE>   54

NOTE: REDACTED PORTIONS HAVE BEEN MARKED WITH (***). THE REDACTED PORTIONS ARE
SUBJECT TO A REQUEST FOR CONFIDENTIAL TREATMENT THAT HAS BEEN FILED WITH THE
SECURITIES AND EXCHANGE COMMISSION.

                                   SCHEDULE I

(***)



<PAGE>   55

NOTE: REDACTED PORTIONS HAVE BEEN MARKED WITH (***). THE REDACTED PORTIONS ARE
SUBJECT TO A REQUEST FOR CONFIDENTIAL TREATMENT THAT HAS BEEN FILED WITH THE
SECURITIES AND EXCHANGE COMMISSION.

                                   SCHEDULE J

                    [ADVANCED SWITCHING COMMUNICATIONS LOGO]

(***)



<PAGE>   56
NOTE: REDACTED PORTIONS HAVE BEEN MARKED WITH (***). THE REDACTED PORTIONS ARE
SUBJECT TO A REQUEST FOR CONFIDENTIAL TREATMENT THAT HAS BEEN FILED WITH THE
SECURITIES AND EXCHANGE COMMISSION.

                                   SCHEDULE K

                           PENDING INFRINGMENT CLAIMS


1. Nortel - Supplier received a letter from Nortel alleging that Supplier's
products infringe one of Nortel's patents relating to inverse multiplexing over
ATM. Supplier believes such allegation is without merit. Per Article 17.8 of the
Agreement, Supplier fully indemnifies Qwest of against any losses related to
such claim.

<PAGE>   57

NOTE: REDACTED PORTIONS HAVE BEEN MARKED WITH (***). THE REDACTED PORTIONS ARE
SUBJECT TO A REQUEST FOR CONFIDENTIAL TREATMENT THAT HAS BEEN FILED WITH THE
SECURITIES AND EXCHANGE COMMISSION.

                                   SCHEDULE L


                         MUTUAL NONDISCLOSURE AGREEMENT


        This Mutual Nondisclosure Agreement ("Agreement"), is made and entered
into as of the date signed by the last person to sign, by and between ADVANCED
SWITCHING COMMUNICATIONS, INC., a corporation organized and existing under the
laws of the State of Delaware with a principal place of business at 8330 Boone
Boulevard, 5th Floor, Vienna, Virginia 22182 ("ASC") and
______________________________ corporation organized and existing under the laws
of the State of ______________________ and having a principal place of business
at ___________________________________________________________________________
and all subsidiary, affiliated and associated companies ("____________"). ASC
and ____________________ are sometimes referred to hereinafter singly as "party"
and collectively as "parties".


                               W I T N E S S E T H

        WHEREAS, the parties desire to communicate certain information which is
proprietary and/or confidential to the disclosing party; and

        WHEREAS, the parties each agree to treat such proprietary information of
the other party under the terms and conditions of this Agreement.

        NOW, THEREFORE, in consideration of the mutual covenants and Promises
herein set forth, the parties hereto agree as follows:

1.      DISCLOSURE OF INFORMATION: The parties hereto agree to disclose and
        provide to each other certain information. The parties hereto recognize
        and agree that the information disclosed by either of the parties hereto
        may be proprietary and/or confidential information. In the event
        proprietary and/or confidential information is disclosed, it shall be
        conspicuously identified as such. To the extent that oral information is
        disclosed by either party, such oral information shall be deemed to be
        proprietary and/or confidential if it is reduced to written or other
        tangible form within fourteen (14) days of the oral disclosure and the
        written or other tangible form is conspicuously identified as
        proprietary and/or confidential. The parties acknowledge that such
        proprietary and/or confidential information is a valuable, special, and
        unique asset belonging to the party that discloses such information. The
        parties agree that they shall not, during or after the term of this
        Agreement, disclose any proprietary and/or confidential information of
        the other party to any person, firm, corporation, association, or any
        other entity for any reason or purpose whatsoever. The parties further
        agree that they shall not utilize, employ, exploit or in any other
        manner whatsoever use the proprietary and/or confidential information
        disclosed by the other party for any purpose without the express written
        consent of the disclosing party.

2.      EMPLOYEES AND AGENTS: The parties agree to limit dissemination of the
        other party's proprietary and/or confidential information to only those
        of the receiving party's officers, directors, agents and employees who
        have a bona fide need for access to said information, to maintain a list
        or log of the names of their employees or agents given access to said
        information, and to disclose said list or log to the other party upon
        request. All persons who receive or have access to proprietary and/or
        confidential information disclosed under this agreement shall have
        previously executed a written agreement which, either directly or
        indirectly, obligates such person to comply with the obligations and
        restrictions contained in this Agreement.

3.      STANDARD OF CARE: The parties agree that they shall protect the
        proprietary and/or confidential information of the other party using not
        less than the same standard of care that each party applies to its own
        proprietary and/or confidential information.



<PAGE>   58

NOTE: REDACTED PORTIONS HAVE BEEN MARKED WITH (***). THE REDACTED PORTIONS ARE
SUBJECT TO A REQUEST FOR CONFIDENTIAL TREATMENT THAT HAS BEEN FILED WITH THE
SECURITIES AND EXCHANGE COMMISSION.

4.      RECORDS AND DOCUMENTS: The parties agree that all records and documents
        containing proprietary and/or confidential information shall be stored
        and handled in such a way as to prevent unauthorized disclosure. The
        parties further agree that, upon the conclusion of the transaction
        between the parties, or upon demand by either party, all documents,
        records, or exhibits labeled as proprietary and/or confidential
        information shall be returned to the party that disclosed such
        information, without retaining any copies thereof, said documents to be
        returned as soon as reasonably practicable.

5.      EFFECT OF RESTRICTIVE LEGENDS: In the event any information,
        documentation or devices disclosed or made available by one party to the
        other contain one or more of the disclosing party's restrictive or
        proprietary legends, such legends shall not impose any obligations or
        restrictions upon the receiving party other than those specifically set
        forth in this Agreement.

6.      PATENTS, COPYRIGHTS, AND TRADEMARKS: Nothing contained in this Agreement
        shall be construed as granting or conferring, by implication, estoppel
        or otherwise, any license or rights under any patent, trademark,
        copyright, trade secret or other proprietary right (whether present or
        future), and no such license or other rights shall arise from this
        Agreement or from any acts, statements or dealings resulting from or
        related to the execution of this Agreement or the performance of the
        obligations of the parties hereunder.

7.      EXCLUSIONS: The provision of this Agreement shall not apply to data or
        information in the public domain at the time it was disclosed, or that
        can be demonstrated to have been known to the party receiving it at the
        time of disclosure, or that becomes known to the receiving party
        independently of the disclosing party without breach of this Agreement.
        If, at the time of the disclosure of confidential and/or proprietary
        information hereunder, the party receiving the information has
        previously known the information, or if, thereafter, the information
        disclosed becomes known to the receiving party independently of the
        disclosing party, then the receiving party shall promptly notify the
        disclosing party that the information has previously been known or has
        become known to the receiving party. If any proprietary and/or
        confidential information is ordered produced or disclosed pursuant to
        subpoena or court order, the receiving party shall first give the
        disclosing party prompt notice of such request so that the disclosing
        party has an opportunity to defend, limit or protect against such
        production or disclosure.

8.      PREVENTION OF DISCLOSURE: Upon discovery that proprietary information
        has been or may be disclosed, the parties agree to take such action as
        may be necessary and proper to prevent the threatened or continued
        disclosure of proprietary information and to pursue such other and
        further legal and/or equitable remedies as may be available.

9.      REPRESENTATIONS: Each party represents and warrants to the other that it
        is a corporation duly organized and validly existing in the state
        indicated in this Agreement and is or will become duly qualified and in
        good standing as a foreign corporation under the laws of all states in
        which it is required to be qualified. Further, each party represents
        that it has full corporate power and authority to enter into this
        Agreement and to do all things necessary for the performance of this
        Agreement.

10.     WAIVER OF BREACH: Any waiver by either party hereto of a breach of any
        of the provisions of this Agreement by the other party shall not operate
        or be construed as a waiver by either party of any rights or privileges
        of either party hereunder or of any subsequent breach.

11.     CONTROLLING LAW: This Agreement shall be construed, interpreted, and
        administered in accordance with the laws of the Commonwealth of
        Virginia.

12.     SEVERABILITY: If for any reason any provision of this Agreement shall be
        declared void or invalid, such declaration shall not affect the validity
        of the remainder of this Agreement which shall remain in full force and
        effect as if executed with the void or invalid provision eliminated.

                                 Page 2 of 3
<PAGE>   59

NOTE: REDACTED PORTIONS HAVE BEEN MARKED WITH (***). THE REDACTED PORTIONS ARE
SUBJECT TO A REQUEST FOR CONFIDENTIAL TREATMENT THAT HAS BEEN FILED WITH THE
SECURITIES AND EXCHANGE COMMISSION.

13.     COUNTERPARTS: This Agreement may be executed and/or conformed in any
        number of counterparts, each of which shall be deemed an original.

14.     BINDING EFFECT: This Agreement shall be binding upon, and shall inure to
        the benefit of each of the parties hereto and their successors in
        interest.

15.     ASSIGNMENT: This Agreement, and the rights and obligations hereby
        created, may not be assigned by either of the parties hereto without the
        express written consent of the other party hereto, said consent not to
        be unreasonably withheld.

16.     ATTORNEY'S FEES: In the event that either party hereto breaches any of
        the terms and conditions of this Agreement then, in addition to such
        remedies or damages as may be recoverable, whether at law or in equity,
        the non-breaching party shall be entitled to recover all costs, expenses
        and attorney's fees actually incurred in enforcing the terms and
        conditions of this Agreement.

17.     MERGER: This Agreement contains the sole, complete and entire agreement
        and understanding of the parties concerning the matters contained
        herein. No statements, promises or representations have been made by any
        party to the other, or are relied upon, and no consideration has been or
        is offered, promised, expected or held out, other than as stated in this
        Agreement. The parties hereto represent that, in entering into this
        Agreement, they have not relied upon any representations other than
        those expressly set forth herein. No conditions precedent to the
        effectiveness of this Agreement exist, other than as may be expressly
        provided herein. There are no oral or written collateral agreements. All
        prior discussion and negotiations have been, and are, merged and
        integrated into, and superseded by, this Agreement.

        IN WITNESS WHEREOF, the duly authorized representatives of the parties
        have caused this Agreement to be executed and effective as of the dates
        indicated below.


ADVANCED SWITCHING COMMUNICATIONS, INC.,
<TABLE>
<S>                                                                     <C>
                                                                           --------------------------------------------

a                      Delaware                        corporation.       a                         corporation.
 -----------------------------------------------------                     ------------------------

BY:                                                                       BY:
   ---------------------------------------------------                        -----------------------------------------
                      (Signature)                                                            (Signature)

Name                                                                      Name
(Printed):                                                                (Printed):
         ---------------------------------------------                               ----------------------------------
Title:                                                                    Title:
         ---------------------------------------------                          ---------------------------------------
Date:                                                                     Date:
         ---------------------------------------------                          ----------------------------------------
</TABLE>

                                  Page 3 of 3
<PAGE>   60




NOTE: REDACTED PORTIONS HAVE BEEN MARKED WITH (***). THE REDACTED PORTIONS ARE
SUBJECT TO A REQUEST FOR CONFIDENTIAL TREATMENT THAT HAS BEEN FILED WITH THE
SECURITIES AND EXCHANGE COMMISSION.

                                   SCHEDULE M

                           ASC PRODUCT SPECIFICATIONS


A-1240 SPECIFICATIONS



A-1240 NETWORK INTERFACES
24 DSX-1 Ports
-  Connector: 100-pin female SCSI, rear panel
-  Pigtail cable included: SCSI to dual 50 pin Amphenol female
-  ATM speed: clear channel at full T1
-     FR speed:  full/fractional (Nx64) T1
-     Frame formats: SF (D4) or ESF
-  Line code: B8ZS or AMI

1 DS-3 Port option for single-slot chassis
-  Connector: dual BNC, 75(OMEGA), rear panel
-  Frame formats: C-bit or M23
-  Line code: B3ZS

A-1240E NETWORK INTERFACES
24 E1 Ports
-  Connector: 100-pin female SCSI, rear panel
-  Pigtail cable (SCSI to dual 50 pin telco female) included
-  ATM speed: clear channel at full E1
-  FR speed:  full/fractional (Nx64) E1
-  Frame formats per ITU-T G.704:
       E1-CRC CAS enabled
       E1-CRC CAS disabled
       E1-CAS disabled
       E1-CAS enabled
-  Line code: HDB3 or AMI

1 E3 Port option for single-slot chassis
-  Connector: dual BNC 75(OMEGA) rear panel
-  Speed: clear channel at full E3
-  Frame formats:
      ITU-T G.832 ADM mapping
      ITU-T G.751 ADM mapping
      ITU-T G.751 PLCP mapping
-  Line code: HDB3

ETHERNET/VLAN INTERFACE (ORDERABLE OPTION - BOTH MODELS)
-  IEEE 802.1Q virtual bridged local area network
-  VLAN-to-PVC mapping
-  Access via 10/100BaseT Ethernet

PROTOCOL SUPPORT
ATM
-  ATM UNI 3.0, 3.1, 4.0
-  Virtual UNI on network-side port
-  ILMI
-  Connections: VPCC, PVCC, PVPC
-  Class of service categories:
       CBR, nrtVBR, rtVBR, and UBR
       Per VC Queuing
       14 assignable priorities plus two default priorities
-  Informational CAC
-      Traffic policing: single and dual leaky bucket
-      Congestion control: AAL5 autodetect with EPD and PPD procedures
-      Cell payload scrambling options
-      F4 and F5 OAM Support

IMA(Orderable Option)
-      ATM Forum inverse multiplexing over ATM (IMA) 1.0, 1.1
-      Up to 12 groups, up to eight circuits per group
Frame Relay (Orderable Option)
-  UNI (FRF.1.1 and FRF.4)
-  NNI (FRF.2.1 and FRF 10)
-  LMI/Annex A, Annex D, gang of four
-  CIR policing, FECN/BECN
-  Per VC queuing
-  14 assignable priorities plus one default

Multilink Frame Relay (MFR)
-      Frame Relay Forum multilink frame relay (MFR) FRF.16
-      MFR available for access or network connections

ATM-to-Frame Relay Interworking
-      Network interworking FRF.5
-      Service interworking FRF.8 -- transparent mode & translation mode
-      ILMI/LMI interworking
-      EFCI-to-FECN/BECN mapping
-      CLP-to-DE mapping

TDM (circuit emulation) (Orderable Option)
-   Non-structured CES for clear channel T1/E1
-   Structured CES for Nx64 fractional T1/E1
-   Channel associated signaling (CAS)
-   Point to multi-point support
-   AF-vtoa-0078.000
-   AF-vtoa-0085.000
-   ITU-T Rec I.363 B-ISDN ADM adaptation layer (AAL) specification

MANAGEMENT & USER INTERFACE
-  HTTP manager for standard Web-browser access
-  Full SNMP v1 agent includes traps for dynamic alarming
-  ASCII configuration file upload/download via FTP over 10BaseT
     Ethernet port or in-band
-  CLI manager via Telnet over 10/100BaseT Ethernet or craft port (front panel
     DB-9 female connector) or in-band
-  Extensive physical layer and network protocol statistics
-  Detailed status per port and per connection
-  Field upgradeable FLASH file system holds dual code loads and configurations;
upload and download by FTP

TIMING SOURCES
-  Internal timing: free-running stratum level 3
-  External timing: BITS A and B primary reference source via wire wrap pins
-  Line timing: from any T1/E1 or T3/E3 interface
-  User-definable timing hierarchy

ALARMS, VISUAL DIAGNOSTICS
-  Event and alarm log with timestamps in NVRAM
-  Physical port and VC statistics collection in NVRAM
-  Critical, major and minor alarm contact closures with front panel LEDs and
alarm cut off
-  Front panel LEDs for power, timing, fan fail, each T1/E1 and T3/E3 port.
-  Line status LED for each T1/E1
-  Alarms: RDI, LOS, LOF, OOF, AIS
-  BERT line testing on any access or network port

CERTIFICATIONS
-  Safety: UL 1950, EN 60950/IEC950, CSA 22.2 950
-  Emissions: EN 55022/CISPR 22, FCC Part 15 Class A
-  Immunity: EN 61000
-  NEBS Level 3: GR-1089, GR-63
-  CE approved

ENVIRONMENTAL
-  Size: 1.75" (1U) H x 19"W x 18"D
-  Rackmountable, center or flush mount.
-  Operating temp: 0(degrees) to 40(degrees) C, short term
      -5(degrees) to 50(degrees) C
-  Temperature storage: -40(degrees) to 70(degrees)C
-  Humidity: 5% to 80% (relative, non condensing)
-  Weight: 9 lbs.
-  Dual voltage input feeds:  -48 VDC @ 1.7A
-  Optional external AC power supply
-  Typical DC power: under 50 Watts, 168 BTU
-  Max DC power: 85 Watts, 286 BTU
-  Cooling: field serviceable air filter and fan tray with redundant fans

ORDERING INFORMATION
Base System:
   Available in T1 and E1 versions
   24 T1 or E1 ports, ATM support
   Pigtail cable, SCSI to dual 50 pin telco female
   Rackmountable chassis
Orderable options:
   T3 or E3 port
   Frame relay support
   MFR software
   IMA software
   ATM-to-frame relay interworking
   Ethernet VLAN support
   CES support
   External AC power supply

CONTACT INFO
Advanced Switching Communications
8330 Boone Blvd., 5th Floor
Vienna VA 22182
Tel (703) 448-5540   Fax (703) 448-5590
www.asc.com

All contents (C) ASC, Inc. and subject to change.1/00


<PAGE>   61
NOTE: REDACTED PORTIONS HAVE BEEN MARKED WITH (***). THE REDACTED PORTIONS ARE
SUBJECT TO A REQUEST FOR CONFIDENTIAL TREATMENT THAT HAS BEEN FILED WITH THE
SECURITIES AND EXCHANGE COMMISSION.

A-2000 SPECIFICATIONS A-2000 NETWORK INTERFACES
4 DSX-3 Ports
-  Connector: dual BNC 75(OMEGA) rear panel
-  Speed: clear channel at full DS-3
-  Frame formats: C-bit parity or M23
-  Line code: B3ZS

1 OC-3c Port Option for single-slot chassis
-  Connector: dual SC duplex female, front panel
-  Single-mode or multi-mode order option
-  Frame format:  I.432/G.709 SONET

A-2000E NETWORK INTERFACES
4 E3 Ports
-  Connector: dual BNC 75(OMEGA) rear panel
-  Speed: clear channel at full DS-3
-  Frame formats:
       ITU-T G.832 ADM mapping
       ITU-T G.751 ADM mapping
       ITU-T G.751 PLCP mapping
-  Line Code: HDB3

1 OC-3c port option for single-slot chassis
-  Connector: dual SC duplex female, front panel
-  Single-mode or multi-mode order option
-  Frame format:  I.432/G.709 SDH STM-1

PROTOCOL SUPPORT
ATM
-  ATM UNI 3.0, 3.1, 4.0
-  Virtual UNI on network-side port
-  ILMI
-  Connections: VPCC, PVCC, PVPC
-  Class of service categories:
        CBR, nrtVBR, rtVBR, and UBR
        Per VC queuing
        14 assignable priorities plus one default priority
-  Informational CAC
-  Traffic policing: single and dual leaky bucket options
-  Congestion control: AAL5 autodetect with EPD and PPD procedures

Frame Relay DS-3/E3 Ports Only
-  2 Byte DLCI
-  UNI (FRF.1& FRF.4)
-  NNI (FRF.2 & FRF.10)
-      FR/ATM service interworking - FRF.8
-      FR/ATM network interworking - FRF.5
-      LMI/annex A, annex D
-      CIR policing, FECN/BECN
-      Per VC queuing
-      15 assignable priorities including one default

       DS-3 RFC 2496
-      Extensive physical layer and network protocol statistics
-      Per-port and per-connections detailed status with user-configurable
       polling



ALARMS & VISUAL DIAGNOSTICS
-  Event and alarm log in NVRAM
-  Physical port and VC statistics collection in NVRAM


<PAGE>   62

NOTE: REDACTED PORTIONS HAVE BEEN MARKED WITH (***). THE REDACTED PORTIONS ARE
SUBJECT TO A REQUEST FOR CONFIDENTIAL TREATMENT THAT HAS BEEN FILED WITH THE
SECURITIES AND EXCHANGE COMMISSION.


-  Critical, major and minor alarms contact closures with front panel LEDs and
alarm cut off
-  Front panel LEDs for power, timing, fan fail and OC-3c mux port.
-  Line status LED for each DS-3
-  Loopbacks: local and remote
-  Alarms: RDI, AIS, LOS, LOF, OOF
CERTIFICATIONS
-  Safety: UL 1950, EN 60950/IEC950, CSA 950
-  Emissions: EN 55022/CISPR 22
-  Immunity: EN 61000
-  NEBS level 3: GR-1089, GR-63
-  CE approved

ENVIRONMENTAL
-  Size: 1.75"(1U) H x 19" W x 18"D
-  Rackmountable center or flush mount
-  Operating temp: 0(degrees) to 40(degrees) C, short
        term -5(degrees) to 50(degrees) C
-  Temperature storage: -40(degrees) to 70(degrees)C
-    Humidity: 5% to 80% (relative, non condensing)
-  Weight: 9 lbs.
-    Dual voltage input feeds:  -48 VDC @ 1.7A, via 2 euro block connectors
-    Typical DC power: under 50 watts, 168 BTU
-  Max DC power: 85 watts, 286 BTU
-  Cooling: field serviceable air filter and fan tray with redundant fans













A-2000 NETWORK INTERFACES
4 DSX-3 Ports
-  Connector: dual BNC 75(OMEGA) rear panel
-  Speed: clear channel at full DS-3
-  Frame formats: C-bit parity or M23
-  Line code: B3ZS

1  OC-3c Port Option for single-slot chassis
-    Connector: dual SC duplex female, front panel
-    Single-mode or multi-mode order option
-    Frame format:  I.432/G.709 SONET

A-2000E NETWORK INTERFACES
4 E3 Ports
-  Connector: dual BNC 75(OMEGA) rear panel
-  Speed: clear channel at full DS-3
-  Frame formats:
     ITU-T G.832 ADM mapping
     ITU-T G.751 ADM mapping
     ITU-T G.751 PLCP mapping
-  Line Code: HDB3

1 OC-3c port option for single-slot chassis
-    Connector: dual SC duplex female, front panel
-    Single-mode or multi-mode order option
-    Frame format:  I.432/G.709 SDH STM-1

PROTOCOL SUPPORT
ATM
- ATM UNI 3.0, 3.1, 4.0

<PAGE>   63
[ASC LOGO]                                                               A-4000



                                  SCHEDULE M

-  Virtual UNI on network-side port
-  ILMI
-  Connections: VPCC, PVCC, PVPC
-  Class of service categories:
        CBR, nrtVBR, rtVBR, and UBR
        Per VC queuing
        14 assignable priorities plus one default priority
-  Informational CAC
-  Traffic policing: single and dual leaky bucket options
-  Congestion control: AAL5 autodetect with EPD and PPD procedures

Frame Relay DS-3/E3 Ports Only
-  2 Byte DLCI
-  UNI (FRF.1& FRF.4)
-  NNI (FRF.2 & FRF.10)
-    FR/ATM service interworking - FRF.8
-    FR/ATM network interworking - FRF.5
-    LMI/annex A, annex D
-    CIR policing, FECN/BECN
-    Per VC queuing
-    15 assignable priorities including one default

MANAGEMENT & USER INTERFACE
-  HTTP manager for standard Web-browser access
-  Full SNMP v1 agent includes traps for dynamic alarming
-    FLASH memory-based file system holds dual code loads and configurations
-  ASCII configuration file upload/download via FTP over 10BaseT or in-band
-  Command line interface via telnet over 10BaseT or via front-panel craft
       port (DB-9 female connector) or via in-band
-  MIB support includes:
     MIB II support with extensions
     Enterprise MIB
     MIB II RFC 2233
     ATM MIB RFC 2515
     OC-3c SONET RFC 2558
     DS-3 RFC 2496
-    Extensive physical layer and network protocol statistics
-    Per-port and per-connections detailed status with user-configurable polling

TIMING SOURCES
-  Internal: stratum level 3
-     External: BITS A and B primary Reference source via wire wrap pins
-  Line: DSX-3 or OC-3c interface
-  User-definable timing hierarchy

ALARMS & VISUAL DIAGNOSTICS
-  Event and alarm log in NVRAM
-  Physical port and VC statistics collection in NVRAM
-     Critical, major and minor alarms contact closures with front panel LEDs
        and alarm cut off
-     Front panel LEDs for power, timing, fan fail and OC-3c mux port.
-     Line status LED for each DS-3
-     Loopbacks: local and remote
-     Alarms: RDI, AIS, LOS, LOF, OOF
CERTIFICATIONS
-  Safety: UL 1950, EN 60950/IEC950, CSA 950
-  Emissions: EN 55022/CISPR 22
-  Immunity: EN 61000
-  NEBS level 3: GR-1089, GR-63
-  CE approved

ENVIRONMENTAL
-  Size: 1.75"(1U) H x 19" W x 18"D
-  Rackmountable center or flush mount



<PAGE>   64
[ASC LOGO]                                                               A-4000

                                   SCHEDULE M


-  Operating temp: 0(degrees) to 40(degrees) C, short
     term -5(degrees) to 50(degrees) C
-  Temperature storage: -40(degrees) to 70(degrees)C
-  Humidity: 5% to 80% (relative, non condensing)
-  Weight: 9 lbs.

































A-4000 CONNECTIONS CAPABILITY SUMMARY
<TABLE>
<CAPTION>
                                     ------------------------------------------------------------------------------------
                                          AVAILABLE CARD               PORTS                       PROTOCOLS
<S>                                     <C>                      <C>                    <C>
=========================================================================================================================

             14 ACCESS SLOTS              A-1000                     12 T1/E1                  ATM, IMA, FR, MFR
                               ------------------------------------------------------------------------------------------
                                          A-1240                     24 T1/E1                ATM, IMA, FR, MFR, TDM
                               ------------------------------------------------------------------------------------------
                                          A-2000                      4 T3/E3                       ATM, FR
=========================================================================================================================
             4 NETWORK SLOTS              A-2000                      4 T3/E3                         ATM
                               ------------------------------------------------------------------------------------------

                                                                     1 OC-3c*

                                          A-5010                      1 STM-1                         ATM
-------------------------------------------------------------------------------------------------------------------------
                                                                                  *Multi mode/short haul or single
                                                                                    mode/Intermediate reach options
</TABLE>







SPECIFICATIONS


<PAGE>   65


                                   SCHEDULE M



ACCESS-PORTS MODULES

A-1000 AND A-1000E
-  12 DSX-1/E1 ports individually configurable for ATM, inverse multiplexing
     over ATM (IMA), frame relay, multilink frame relay (MFR)
-  50-pin female telco connector
-  Speed: clear channel at full T1 rates or Nx64 fractional rates
-   Frame formats     T1 model:  SF (D4) or ESF
                      E1 model:  ITU-T G.704
-  Line codes         T1 model:  B8ZS, AMI
                      E1 model:  HDB3, AMI

A-1240 AND A-1240E
-  24 DSX-1/E1 ports individually configurable for ATM, IMA, frame relay, MFR
     or TDM (CES)
-  100 Pin SCSI, pigtail to two 50-pin female Telco connectors.
-  Speed: clear channel at full T1 rates or Nx64 fractional rates
-    Frame formats   T1 model:  SF (D4) or ESF
                     E1 model:  CCITT, G.704
-  Line codes        T1 model:  B8ZS, AMI
                     E1 model:  HDB3, AMI

A-2000 AND A-2000E
-  4 T3/E3 ATM, frame relay

-  Dual BNC, 75(OMEGA) connector
-  Speed: clear channel
-  Frame formats
       T3 model:    C-bit parity, M23
       E3 model:    ITU-T G.832 ADM mapping
                    ITU-T G.751 ADM mapping
                    ITU-T G.751 PLCP mapping
-  Line code        T3 model:          B3ZS
                    E3 model:          HDB3

NETWORK-PORTS MODULE

A-2000 AND A-2000E (SEE ABOVE)

A-5010 MODULE
-      One ATM OC-3c/STM-1 port
-      Multi mode/short haul or single mode/intermediate reach options
-  Connector: DIN 47256 on front panel
-      Frame format:  I.432/G.709 SONET or STM-1, software configurable

Refer to data sheets for these ASC products for more information


<PAGE>   66

                                   SCHEDULE M

HIGH AVAILABILITY
        -   All cards are hot swappable
        -   Fault resilient backplane
        -   Redundant timing
        -   Redundant network management
        -   Redundant BITS interfaces
        -   Redundant CO alarm contact closures
        -   Redundant, hot swappable fan trays
        -   Dual DC feeds
        -   AC version with load sharing/redundant AD/DC rectifiers

MANAGEMENT & USER INTERFACE
-  Ethernet management interface
-  Embedded HTTP server supports management from standard Web browser
-  Full-featured command line interface via front panel DB-9 female connector
      craft port or inband RFC 1483 connection
-     Upload/download ASCII configuration files via FTP over Ethernet or inband
-     SNMP agent includes traps defined for dynamic alarming

TIMING
-  Internal stratum level 3
-  Timing modes: free run, external BITS, line (access or mux), or loop

CERTIFICATIONS
-  Safety: UL 1950, EN 60950/IEC950, CSA 22.2 950, CE
-  Emissions: EN 55022/CISPR 22, FCC Part 15 class A, CE
-  Immunity: EN 61000, CE
-  NEBS level 3: GR-1089, GR-63

ENVIRONMENTAL
-  Size: 24.5"(14U) H  x  17.5" W  x  20"D
-  Rackmountable center or flush mount
-  Operating temperature: 5(degree) to 40(degree) C
-  Temperature short term: -5(degree) to 50(degree) C
-  Temperature storage: -40(degree) to 70(degree)C



                                                                    [ASC LOGO]
<PAGE>   67

                                   SCHEDULE M

-  Humidity: 5% to 80% (relative, non condensing)
-  Altitude: -197 to 10,000 ft
-  Weight: 103 lbs. fully loaded
-  Dual voltage input feeds:  -48 VDC @ 20 amps fully loaded
-  Optional AC power converter
-  Max. power consumption: DC dissipation 1000 watts
-  Cooling: field-serviceable air filter and dual fan trays

CONTACT
Advanced Switching Communications
8330 Boone Blvd.
5th Floor, Vienna VA 22182
Tel (703) 448-5540   Fax (703) 448-5590
www.asc.com

All contents (C) ASC, Inc. and subject to change. 1/00






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