Document:

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                                                                   EXHIBIT 10.22

CONFIDENTIAL TREATMENT HAS BEEN REQUESTED FOR CERTAIN REDACTED PROVISIONS OF
THIS AGREEMENT. THE REDACTED PROVISIONS ARE IDENTIFIED BY THREE ASTERISKS
ENCLOSED BY BRACKETS AND UNDERLINED. THE CONFIDENTIAL PORTION HAS BEEN FILED
SEPARATELY WITH THE SECURITIES AND EXCHANGE COMMISSION.

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                               LICENSING AGREEMENT

                                 BY AND BETWEEN

                        DITECH COMMUNICATIONS CORPORATION
                                 (TELINNOVATION)

                                       AND

                           ACCELERATED NETWORKS, INC.

                                      DATED

                                  JULY 15, 1999
                                  (AS AMENDED)

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                               LICENSING AGREEMENT

               THIS agreement ("Agreement") is entered into as of the _____ day
of December, 1998 ("Effective Date),

BETWEEN:       ACCELERATED NETWORKS CORPORATION, a corporation
               existing under the
               laws of California, and having a
               place of business at 301 Science
               Drive, Moorpark, California, U.S.A.
               93021

               (hereinafter called "Accelerated Networks")

AND:           TELINNOVATION SERVICE CORPORATION,
               a corporation existing under the
               laws of California, and having a
               place of business at 415 Clyde
               Avenue #105, Mountain View, California,
               U.S.A. 94043.

               hereinafter called "Telinnovation")

               WHEREAS Telinnovation has certain echo cancellation digital
signal processing technology;

               AND WHEREAS Accelerated Networks is a manufacturer of
telecommunications equipment;

               AND WHEREAS Accelerated Networks desires to be able to
incorporate Telinnovation's echo cancellation digital signal processing
technology in certain of its products and to obtain certain rights with respect
thereto, and Telinnovation is prepared to grant such rights.

               THEREFORE the parties agree as follows:

ARTICLE 1 - DEFINITIONS

1.1     As used in this Agreement and schedules hereto:

        (a)    "Affiliate" means Accelerated Networks, its parent corporation
               and any corporation or company which Accelerated Networks or its
               parent company effectively controls, directly or indirectly
               through the ownership or control of shares in such corporation
               the right to sell to End Users products containing the Product.

        (b)    "Distributor" means any third party to whom Accelerated Networks
               or any Affiliate grants.

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        (c)    "Documentation" means the documentation regarding the Technology
               set forth on Exhibit C hereto, together with all documentation to
               be developed for the Developed Technology.

        (d)    "End User" means any person, firm or corporation which acquires
               any products referred to in subsection (b) above.

        (e)    "Technology" means the fundamental digital signal processing
               algorithm owned by Telinnovation prior to the execution of this
               Agreement which are intended to perform an echo canceling
               function and/or other signal enhancement or modification.

        (f)    "Developed Technology" means that technology provided by
               Telinnovation conforming to the Developed Technology
               Specification set forth in Schedule A, all enhancements thereto,
               and all applicable documentation.

        (g)    "Products" shall mean the Accelerated Networks' products listed
               in Schedule A.

        (h)    "Manufacturing Licensee" shall mean any third party who acquires
               or has acquired from Accelerated Networks or an Affiliate the
               right to manufacture a product or products into which Accelerated
               Networks or an Affiliate incorporates the Product.

        (i)    "Developed Technology Specification" means the specification set
               forth in Schedule A.

ARTICLE 2 - LICENSING

2.1     Telinnovation grants to Accelerated Networks and Affiliates a
        non-exclusive, worldwide license to (a) incorporate the Technology and
        the Developed Technology and any derivative works thereof into the
        Products and into Products manufactured by third parties for Accelerated
        Networks and Affiliates and by Manufacturing Licensees, and (ii) to
        license the Technology and the Developed Technology incorporated into or
        bundled with the Products, to End Users. The parties agree that
        Accelerated Networks may use Distributors to distribute products
        incorporating and/or bundled with the Products.

ARTICLE 3 - TITLE

3.1     Telinnovation represents and warrants that Telinnovation owns all right,
        title, and interest in and to the Technology, the Developed Technology,
        and the Products and that it has full power and authority to perform all
        of its obligations hereunder and that Accelerated Networks shall obtain
        all rights, title and interest stated in this Agreement free and clear
        of any encumbrances and restrictions; without requiring the consent of
        any other person, firm or corporation.

3.2     Subject to 3.6, Telinnovation hereby indemnifies and saves harmless
        Accelerated Networks, Affiliates, Distributors, and End Users from and
        against any and all losses,

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        costs, liabilities and expenses (including - reasonable counsel fees)
        arising out of any breach or claimed breach of such representation and
        warranty.

3.3     Subject to paragraph 3.6, Telinnovation shall defend at its own expense,
        and, shall have control of the defense of, any and all suits, actions or
        claims against Accelerated Networks, Affiliates, Distributors, and End
        Users charging that any component of the Technology or the Developed
        Technology infringes any patent, trademark, industrial design, trade
        secret, or copyright of any third party, whether the alleged
        infringement pertains to the production, Licensing or use of any part of
        the Developed Technology.

3.4     In the event of any such suit, action or claim the following procedures
        shall apply:

        (a)    the parties shall meet promptly to discuss such claim, suit or
               action and, provided that the parties mutually that Telinnovation
               shall do so, Telinnovation shall, settle such claim, suit or
               action provided that Telinnovation can do so for an amount not
               exceeding, in the aggregate, two point five percent (2.5%) of its
               then total revenues from licensing the Technology or the
               Developed Technology;

        (b)    if the parties are unable to agree on a course of action in
               accordance with subparagraph (a) all fees and royalties
               thereafter payable to Telinnovation by Accelerated Networks,
               shall instead be paid into an escrow fund in an interest bearing
               account in a United States bank until the aggregate amount paid
               into such escrow fund equals two point five percent (2.5%) of
               Accelerated Networks then total revenues from licensing Developed
               Technology. Upon a final judicial decision awarding damages in
               such claim, suit or action, or settlement thereof by
               Telinnovation, Accelerated Networks shall pay the amount of such
               award or settlement up to but not exceeding the amount in the
               escrow fund, using all amounts contained in the escrow fund- Any
               balance in the escrow fund shall be paid to Telinnovation;

        (c)    Accelerated Networks may set off and claim against all fees and
               royalties paid or payable to Telinnovation, any and all amounts
               paid by it under subparagraphs (a) and (b) hereof; and

3.5     Telinnovation will also pay the actual costs including reasonable legal
        fees, and all damages finally awarded in any such suit, and will
        indemnify and save harmless Accelerated Networks, Affiliates,
        Distributors, and End Users from all other expenses thereby incurred,
        provided Telinnovation is notified promptly in writing of the suit,
        action or claim and, at Telinnovation's request and expense, is given
        all assistance and authority, at Telinnovation's expense, reasonably
        required for defense and settlement of same.

3.6     If the use or licensing of any portion of the Technology and/or the
        Developed Technology is permanently enjoined by final judicial decision,
        or subject to any other continuing liability, Telinnovation shall, at no
        expense to Accelerated Networks, as soon as reasonably possible:

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        (a)    obtain for Accelerated Networks and its Affiliates, Distributors,
               and End Users from all persons in the suit who claim an interest
               in the Technology and/or Developed Technology, the right to use
               the Technology and/or Developed Technology; or

        (b)    substitute for the Technology and/or Developed Technology a
               non-infringing equivalent to the Technology and/or Developed
               Technology and extend the indemnity set forth in this Article 3
               thereto; or

        (c)    modify the Technology and/or Developed Technology to make it
               non-infringing but equivalent in function and performance to the
               infringing Technology and/or Developed Technology and provide
               such modified Technology and/or Developed Technology to
               Accelerated Networks and extend the indemnity set forth in this
               Article 3 thereto.

3.7     Telinnovation shall not be responsible for any expense, cost, loss or
        liability of any kind arising out of any suit, action or claim against
        Accelerated Networks, Affiliates, Distributors, or End Users charging
        that any component of the Technology or the Developed Technology
        infringes or misappropriates any Intellectual Property Rights of any
        third party if any such suit, action or claim is based upon part or
        parts of any of the Technology and/or Developed Technology, if, pursuant
        to paragraph 3.4 herein, Telinnovation has substituted or modified the
        Technology and/or Developed Technology, but Accelerated Networks
        nevertheless elects to continue to use the non-modified version of the
        Technology and/or Developed Technology that has been enjoined or
        otherwise burdened with a liability.

3.8     Telinnovation shall not be responsible for any expense, cost, loss or
        liability of any kind arising out of any suit, action or claim against
        Accelerated Networks, Affiliates, Distributors, or End Users charging
        that any component of the Technology and/or Developed Technology
        infringes or misappropriates the intellectual property rights of any
        thud party to the extent that any such suit, action or claim is based
        upon part or parts of any of the Technology and/or Developed Technology
        that have been materially altered or modified by Accelerated Technology
        or its Affiliates without the express written consent of Telinnovation.

ARTICLE 4 - ROYALTIES

4.1     Accelerated Networks shall pay to Telinnovation fees and royalties in
        accordance with Schedule B. Such fees and royalties are exclusive of all
        excise, sales, use or other taxes, fees, duties or levies charged by any
        governmental authority, all of which shall be paid by Accelerated
        Networks; provided, however, that none of Accelerated Networks, its
        Affiliates, Distributors, or End Users shall have any obligation to pay
        any income taxes of Telinnovation.

4.2     Accelerated Networks' all royalties will be paid at the end of
        Accelerated Networks' fiscal quarters.

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4.3     Accelerated Networks agrees to keep and maintain, for a period of two
        (2) years after the end of the year to which they pertain, complete and
        accurate records of the products manufactured and distributed by
        Accelerated Networks which contain the Developed Technology, in order to
        calculate and confirm Accelerated Networks' royalty obligations. Upon
        reasonable prior notice, Licensor will have the right, exercisable not
        more than once every twelve (12) months, to appoint an independent
        accounting firm or other agent reasonably acceptable to Accelerated
        Networks, at Licensor's expense, to examine such financial books,
        records and accounts during Accelerated Networks' normal business hours
        to verify the royalties due by Accelerated Networks, subject to such
        independent accounting firm's or agent's execution of Accelerated
        Networks' standard confidentiality agreement; provided that execution of
        such agreement will not preclude such firm from reporting its results to
        Licensor. In the event such audit discloses an underpayment or
        overpayment of royalties due hereunder, the appropriate party will
        promptly remit the amounts due to the other party shall pay to
        Telinnovation fees and royalties in accordance with Schedule B. Such
        fees and royalties are exclusive of all excise, sales, use or other
        taxes, fees, dudes or levies charged by any governmental authority, all
        of which shall be paid by Accelerated Networks

ARTICLE 5 - REPRESENTATIONS, WARRANTIES, AND COVENANTS

5.1     Telinnovation represents, warrants, and covenants to Accelerated
        Networks that the Technology shall conform to the specifications
        therefor, the Developed Technology shall conform to the Developed
        Technology Specifications set forth on Exhibit A to this Agreement, and
        that each copy of the Developed Technology shall be free from any design
        defects in workmanship and material.

5.2     Telinnovation represents, warrants, and covenants that, at the time of
        delivery thereof to Accelerated Networks, any Technology and the
        Developed Technology shall not contain any virus, "Trojan horse," timer,
        clock counter, or other limiting design, instruction, or routine that
        would erase data or programming or cause any Product to become
        inoperable or otherwise incapable of being used in the full manner for
        which it was designed and created.

5.3     Telinnovation represents, warrants, and covenants that all Technology
        and the Developed Technology shall be Year 2000 Compliant. For purposes
        of this Agreement, "Year 2000 Complaint" means all Technology and the
        Developed Technology shall (a) not be materially affected by any
        inability to completely and accurately address, present, produce, story,
        and calculate data involving dates beginning with April 9, 1999,
        September 9, 1999, and January 1, 2000, and will not produce abnormally
        ending or incorrect results involving such dates as used in any forward
        or regression date-based function; or (b) function in such away that all
        "date' related functionalities and data fields include the indication of
        century and millennium and will perform calculations that involve a
        four-digit year field.

5.4     Telinnovation represents, warrants, and covenants that any services that
        Telinnovation performs for Accelerated Networks, or any Affiliate,
        Distributor, or End User hereunder

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<PAGE>   7

        shall be performed in a timely, competent, professional, and workmanlike
        manned, using qualified employees.

5.5     Telinnovation represents, warrants, and covenants that at all times
        during which this Agreement remains in effect, Telinnovation shall
        comply, and shall insure that the Technology and the Developed
        Technology comply, with all applicable federal, state, and local laws,
        rules, and regulations.

5.6     Telinnovation represents, warrants, and covenants that all Documentation
        delivered to Accelerated Networks under this Agreement shall be complete
        and describe the Technology and the Developed Technology accurately, in
        accordance with industry standards, and with sufficient clarity and
        detail to enable an End User to operate the Technology and Developed
        Technology successfully.

5.7     Telinnovation represents, warrants, and covenants that (a) within thirty
        (30) days of the execution of this Agreement, Telinnovation shall enter
        into with Accelerated Networks an escrow agreement substantially in form
        set forth in Exhibit D hereto pursuant to which Telinnovation shall
        place in escrow all source code for the Developed Technology, together
        with source code documentation, (b) all source code documentation placed
        in escrow in accordance with this Section 5.5 shall be complete and
        describe the source code and all components thereof accurately so as to
        enable reasonably skilled computer programmers who are knowledgeable of
        the subject matter to fully utilize the source code to understand,
        support, and modify the source code to which it relates.

5.8     If the Technology fails to conform to the specifications therefor, the
        Developed Technology or any component thereof fails to conform to the
        Developed Technology Specifications, of the Technology or the Developed
        Technology is defective in material or workmanship, Accelerated Networks
        shall notify Telinnovation of the evidence thereof, and Telinnovation
        shall correct any such non-conformance or defect and deliver the
        Developed Technology to Accelerated Networks for all affected End User
        sites in accordance with the procedures set forth in Exhibit C without
        charge.

ARTICLE 6 - TECHNICAL SUPPORT

6.1     Telinnovation shall develop and provide upgrades, maintenance, training
        and technical advice to Accelerated Networks, its distributors and End
        Users when reasonably requested by Accelerated Networks. Such support
        shall be provided at Telinnovation's current market rates; provided that
        Telinnovation shall not raise its rates for the technical support
        described in this Section 6.1 more than once during each twelve (12)
        month period during which this Agreement remains in effect and shall not
        charge Accelerated Networks more for such technical support than it
        charges to any other licensee of the Technology or the Developed
        Technology.

ARTICLE 7 - CONFIDENTIALITY

7.1     All technical and commercial information, documentation and know-how of
        every kind and description which is market as being confidential
        ("Confidential Information") supplied by one party (the "Supplier") to
        the other (the "Recipient") whether before

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        and/or after execution of this Agreement, as well as other information
        related thereto acquired or developed by Telinnovation in connection
        with this Agreement, shall be (except as otherwise stated herein) the
        exclusive property of the Supplier, and the Recipient shall, for a
        period of five (5) years from termination of this Agreement, treat and
        protect such Confidential Information as the Suppliers proprietary and
        confidential information, and shall not reproduce or divulge said
        Information in whole or in part to third parties except as may be
        required for the performance of its obligations under this Agreement,
        provided such third parties agree in writing prior to such disclosure to
        keep such Confidential Information confidential upon the same terms as
        herein contained. This confidentiality obligation shall survive
        termination or expiry of this Agreement. Notwithstanding the foregoing,
        the Developed Technology and Developed Technology Documentation, with
        the exception of the Technology, shall be owned by Accelerated Networks
        and shall be considered as Confidential information of Accelerated
        Networks. Also notwithstanding the foregoing, the Recipient shall not be
        liable for disclosure of the Information if

        (a)    The Confidential Information enters the public domain other than
               through a breach of this Agreement;

        (b)    the Confidential information is lawfully obtained by the
               Recipient from a third party without breach of this Agreement by
               the Recipient;

        (c)    the Supplier has provided its prior express written approval for
               such disclosure;

        (d)    the Confidential Information was known to the Recipient prior to
               commencement of the Development Project or developed
               independently by Recipient, without use of Supplier's
               Confidential Information, and Recipient can document the same; or

        (e)    disclosure of the Confidential Information is incidental to the
               exercise of rights under other provisions of this Agreement

ARTICLE 8 - TERMINATION

8.1     This Agreement shall remain in full force and effect for a period of one
        (1) year from the Effective Date. Thereafter, this Agreement
        automatically shall renew for successive terms on one (1) year each,
        unless, at least thirty (30) days prior to the end of the then-current
        term, one party provides the other party with written notice of such
        party's intention to terminate this Agreement. Either party may
        terminate this Agreement upon thirty (30) days prior written notice to
        the other party if such other party fails to comply with any of its
        fundamental obligations under this Agreement unless corrective action
        reasonably acceptable to the first mentioned party is commenced within
        such thirty (30) day period and completed within an agreed period, if
        any; provided, however, that if Accelerated Networks in good faith
        disputes whether any payment is due hereunder, Telinnovation may bring
        an action against Accelerated Networks with respect to whether such
        payment is due, but may not terminate this Agreement

8.2     Termination of this Agreement shall, be effective upon completion of the
        applicable notice period in accordance with the foregoing.

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ARTICLE 9 - SCHEDULES

9.1     The following schedules shall constitute an integral part of this
        Agreement:

               Schedule A - Products
               Schedule B - Royalty Payments
               Schedule C - Documentation
               Schedule D - Escrow Agreement
               Schedule E - Service Standards

ARTICLE 10 - SEVERABILITY

10.1    In the event of au enforceable derision or directive declaring invalid
        an essential part of this Agreement, without which this Agreement would
        not have been entered into, this Agreement may, at the option of either
        party, be terminated upon the giving of written notice to the other
        party. Except as aforesaid, if any term, clause, provision or condition
        of this Agreement is similarly adjudged invalid for any reason
        whatsoever, such invalidity shall not affect the validity or operation
        of any other term, clause, provision or condition and such invalid term,
        clause, provision or condition shall be deemed to have been deleted from
        this agreement.

ARTICLE 11 - SURVIVAL

11.1    Notwithstanding any termination or expiry of this Agreement, the
        provisions of Articles 1, 3, 5, 5, 6, 7 and 8 and all consequent rights,
        obligations and liabilities shall survive the termination or expiry of
        this Agreement.

ARTICLE 12 - ASSIGNMENT

12.1    Accelerated Networks shall have the right to assign all or any part of
        its rights or interests under this Agreement to any Affiliate upon
        notice.

12.2    Telinnovation shall not assign all or any part of its rights or
        interests under this Agreement without the prior written consent of
        Accelerated Networks.

ARTICLE 13 - WAIVER

13.1    The failure of either party to enforce at any time or for any period of
        time any of the provisions of this Agreement shall not constitute a
        waiver of such provisions or the right of either party to enforce each
        and every provision.

ARTICLE 14 - GOVERNING LAW

14.1    The rights and obligations -arising under the Agreement shall be
        governed by and construed in accordance with the laws of the State of
        California and the United States of America, excluding, without regard
        to conflicts of laws provisions thereof and without regard to the United
        Nations Convention on Contracts for the International Sale of Goods. The
        sole jurisdiction and venue for actions related to the subject matter
        hereof

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        shall be the state and federal courts having within their jurisdiction
        the location of Accelerated Networks' principal place of business. Both
        parties hereby consent and waive any venue objections to the
        jurisdiction of such courts. The parties agree that process may be
        served in the manner provided herein for giving of notices or otherwise
        as allowed by California or federal law.

ARTICLE 15 - NOTICES

15.1    Any and all notices or other information required to be given by one of
        the parties to the other shall be deemed sufficiently given when
        received following forwarding by prepaid registered mail, or by cable,
        telegram, telex or hand-delivery to the other party at the following
        address:

        If to Accelerated Networks:

                                    Accelerated Networks
                                    301 Science Drive
                                    Moorpark, California 93021
                                    U.S.A.
                                    Attention: President

        If to Telinnovation:

                                    Telinnovation Service Corporation
                                    415 Clyde Avenue #105
                                    Mountain View, CA 94043
                                    U.S.A.
                                    Attention: President

        and such notices shall be deemed to have been received five (5) business
        days after mailing if forwarded by mail, and the following business day
        if forwarded by e-mail, cable, telegram, telex or hand-delivery.

15.2    The aforementioned address of either Party may be changed at any time by
        giving fifteen (15) business days prior notice to the other Party in
        accordance with the foregoing.

15.3    In the event of a generally prevailing labor dispute or other situation
        which will delay or impede the giving of notice by any such means, the
        notice shall be given by such specified mode as will be most reliable
        and expeditious and least affected by such dispute or situation.

ARTICLE 16 - CURRENCY

16.1    All dollar amounts expressed in this Agreement are in U.S. dollars. All
        remittances shall be in U.S. dollars.

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ARTICLE 17 - ENTIRE AGREEMENT

17.1    This Agreement and schedules hereto set forth the entire agreement and
        understanding between the parties and supersede and cancel all previous
        negotiations, agreements, commitments and writings in respect of the
        subject matter hereof and there are no -understandings, representations,
        conditions, warranties, express or implied, statutory or otherwise made
        or assumed by the parties, other than those expressly contained in this
        Agreement Neither party shall be bound by any term, clause, provision or
        conditions save as expressly provided herein or as duly set forth on or
        subsequent to the date of this Agreement in writing signed by duly
        authorized officers of the parties.

               IN WITNESS WHEREOF, the parties have signed this Agreement on the
day, mouth and year first above mentioned.

TELINNOVATION                               ACCELERATED NETWORKS

By:     /s/ Charles S. Davis                By:   /s/ Suresh Nihalani
        -------------------------------           -----------------------------
Name:      Charles S. Davis                 Name:    Suresh Nihalani
           ----------------------------              --------------------------
Title:     President                        Title:   President
           ---------------------------               --------------------------
Date:      12-24-98                         Date:    12-30-98
           ---------------------------               --------------------------

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SCHEDULE A - LICENSED TECHNOLOGY AND DEVELOPED TECHNOLOGY

Developed Technology Specification: echo cancellation software intended to run
on the Texas instruments C54X family of Digital Signal Processors and available
in:

        a.     Stand alone 16-channel canceller (current product)
        b.     C' callable multi channel functions (current product)
        c.     CPE short tail canceller (future product)

               Since the CPE short tail canceller (item c) is unavailable at the
time of this contract, and until the time that this product is available and
offered to Accelerated Networks, Telinnovation agrees to offer the `C' callable
multi channel canceller function (item b) for all Accelerated Networks' CPE
applications.

               Minimum performance of the echo cancellation object code when
running on 80Mhz TMS320C548 DSP must be compliant with the ITU G.165 and G.168
Recommendations and consistent with the performance as described in the
Telinnovation document titled "ECHO CANCELLATION "C"-CALLABLE FUNCTION USER'S
GUIDE FOR THE TMS320C54x FAMILY" REVISION B, dated May 13, 1998.

               When the short tail canceller is available and it meets the CPE
product requirement of Accelerated Networks, it will henceforth be used instead
of the "C' callable multi channel canceller for short tail applications.

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SCHEDULE B - ROYALTY PAYMENTS

               Accelerated Networks shall pay Telinnovation royalties with
respect to sales by Accelerated Networks during the life of the Product.

               The price for the short tail canceller, or for the `C' callable
multi channel canceller when used in a CPE application, shall be [***] of the
regular rate. Volumes will be combined for quantity pricing, but the short tail
canceller volume will be counted at [***].

               The royalty payable by Accelerated Networks shall be on a per
channel end basis. Telinnovation shall submit to Accelerated Networks an invoice
in the amount of [***], covering the first [***] channels. Payment of this
invoice to be paid to Telinnovation immediately after the delivery of the first,
generally available (non-demo, non-beta) product containing Telinnovation code
to an Accelerated Networks customer.

               After the first [***] echo cancellers, additional payments are
specified as per the schedule below:

         Quantity           [***]               [***]                  [***]

         Price ea.          [***]               [***]                  [***]

               Beta tests, field trials and evaluation units are not counted as
shipments and no royalties are due.

---------------
        *** Confidential Treatment has been requested for certain redacted
provisions of this agreement. The redacted provisions are identified by three
asterisks, enclosed by brackets and underlined. The confidential portion has
been filed separately with the Securities and Exchange Commission.

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SCHEDULE C - DOCUMENTATION

11 U G. 168 "Digital Network Echo Canceller" March 1999

ITU G. 165 "Digital Network Echo Cancellers" 19913

Telinnovation "Tms320c54x Echo Canceller DSP Module User's Guide" (Rev F)

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SCHEDULE D - ESCROW AGREEMENT

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                            SOFTWARE ESCROW AGREEMENT

                  This Software Escrow Agreement is entered into as of the 24
day of December 1998, by and among Accelerated Networks Corporation, a
California corporation ("Accelerated Networks"), Telinnovation Service
Corporation, a California corporation ("Telinnovation"), and
_______________________ as Escrow Agent ("Escrow Agent").

                                    RECITALS

                  A. Telinnovation is the owner of certain software set forth on
Exhibit A to this Agreement (including all modifications, changes, enhancements,
conversions, upgrades and/or additions, collectively, the "Telinnovation
Software") which Telinnovation has licensed to Accelerated Networks under the
terms of a technology licensing agreement dated as of Dec 24, 1998 (the
"Licensing Agreement").

                  B. Under the terms of the License Agreement, Telinnovation has
agreed to deposit and maintain a copy of the underlying source code of the most
current released version of the Telinnovation Software with the Escrow Agent for
the benefit of Accelerated Networks, and Escrow Agent agrees to accept such
source code under the terms of this Agreement.

                                   AGREEMENTS

                  In consideration of the recitals and the mutual agreements set
forth herein, the parties agree as follows:

                  1. Escrow of Source Code.

                           (a) Initial Deposit. Telinnovation shall deliver
electronic and paper copies of all high order language and/or assembly language,
as applicable, source code and any link files, compiler and linker instructions,
make files, job control language, library routines and any other similar source
material, as well as complete written instructions for compiling, linking,
loading and executing the software or performing any similar functions and a
complete list, including version number, of all compilers, linkers or other
software development tools (collectively, "Source Code") necessary to generate,
using a standard set of software development tools, a fully executable version
of the Telinnovation Software to the Escrow Agent within fifteen (15) days of
the date of this Agreement.

                           (b) Subsequent Deposits. Within fifteen (15) days of
the delivery to Accelerated Networks of any modifications, changes,
enhancements, conversions, upgrades and/or additions to the Telinnovation
Software, Telinnovation shall deposit the most current version of the Source
Code necessary to generate, using a standard set of software development tools,
a fully executable version of such modified, changed, enhanced, converted,
upgraded, and/or supplemented Telinnovation Software with the Escrow Agent. Upon
deposit of such Source Code, Exhibit A to this Agreement shall be updated to
include such to reflect the applicable modifications, changes, enhancements,
conversions, upgrades, and/or additions. Within fifteen (15) days of the
delivery of any new release of Telinnovation Software, Telinnovation shall
deposit the Source Code for such new release with the Escrow Agent.

                                       15
<PAGE>   17
                           (c) Mechanics of Deposit. Telinnovation shall deliver
any Source Code deposited under this section 1 to Escrow Agent via national
courier service or registered U.S. mail to the address set forth in section 11
of this Agreement. Any such deposit shall include a written description of the
Source Code identifying the software, version number, modifications from the
previous version and any other information required to uniquely identify the
Source Code (the "Deposit Description"). The Deposit Description shall contain a
representation and warranty by Telinnovation that the Source Code is an accurate
and complete representation of the version of the Telinnovation Software,
Telinnovation Application or Other Software described in the Deposit
Description. In the event the Source Code is damaged or destroyed in transit,
Escrow Agent shall notify Telinnovation within three days of the receipt of such
Source Code, and Telinnovation shall deliver a duplicate copy of the Source Code
to the Escrow Agent within seven days of the receipt of such notice.

                           (d) Duties of Escrow Agent. Escrow Agent shall hold
the deposited Source Code, in accordance with the terms and conditions of this
Agreement, in a secure media vault which provides appropriate fire protection
systems and a storage environment which minimizes degradation of the physical
media containing the Source Code. Escrow Agent shall have no obligation to
verify the completeness or accuracy of the Source Code. Escrow Agent shall have
the right to duplicate the Source Code solely as required to comply with the
terms of this Agreement.

                           (e) Notice of Deposit. Upon deposit of the Source
Code into the secure media vault, the Escrow Agent shall notify Telinnovation
and Accelerated Networks via certified mail or national courier service (the
"Deposit Notification"). The Deposit Notification shall include the date the
Source Code was received by the Escrow Agent, the date of its deposit into the
media vault and a copy of the Deposit Description.

                  2. Verification Rights. Accelerated Networks shall have the
right upon ten (10) days' written notice to Telinnovation and Escrow Agent, to
review or to have any or all of the Source Code deposited with Escrow Agent
reviewed to verify that such Source Code conforms to the Telinnovation Software
identified in the appropriate Deposit Description. Such verification shall be
performed by representatives of Accelerated Networks and the Escrow Agent.
Telinnovation may designate a representative to be present at any verification
activities. The Accelerated Networks and/or the Escrow Agent shall issue a
report of its findings (the "Verification Report") within 30 days of the
completion of such activities.

                  3. Release of Source Code to Accelerated Networks. Escrow
Agent is hereby authorized and directed to release the Source Code to
Accelerated Networks under the conditions set forth in this section 3.

                           (a) Notification of Release Condition. Accelerated
Networks may provide written notice to Escrow Agent and Telinnovation of the
occurrence of any of the following conditions ("Release Notification"):

                                    (i) Telinnovation is adjudicated insolvent,
or consents to or acquiesces to the appointment of a receiver or liquidator,
Telinnovation's board of directors or a majority of its shareholders take any
action towards the dissolution or liquidation of

                                       16
<PAGE>   18
Telinnovation, Telinnovation voluntarily or involuntarily becomes a debtor
subject to proceedings under the United States Bankruptcy Code, or makes an
assignment for the benefit of creditors, or a receiver is appointed for
Telinnovation;

                                    (ii) Telinnovation has discontinued
maintenance and support of the Telinnovation Software; or

                                    (iii) for a period of forty-five (45) days
or more from the date on which Telinnovation first received from Accelerated
Networks notice thereof, Telinnovation has been unable to rectify (y) a material
failure of the Telinnovation Software to function in accordance with the
specifications therefor, applicable user documentation, or both; or (z) a
material breach of Telinnovation's warranties set forth in Article 5 of the
Licensing Agreement.

                           (b) Dispute Provisions. Telinnovation shall have
seven days from the receipt of the Release Notification to provide written
notice if it disputes the condition or conditions specified in the Release
Notification (the "Telinnovation Dispute"). Accelerated Networks, upon receipt
of the Telinnovation Dispute, shall contact Telinnovation and the parties shall
make a good faith attempt to resolve the dispute. If the matter is not resolved
by the parties within seven days of Accelerated Networks' receipt of the
Telinnovation Dispute, the matter shall be referred to binding arbitration in
accordance with section 10 of this Agreement, subject to the limitations set
forth in section 3(c) below.

                           (c) Limitations on Arbitration. In the event of
arbitration of a dispute under section 3(b), the entire arbitration process
shall be limited to five (5) working days. The sole issue for arbitration shall
be whether Accelerated Networks is entitled to release of the requested Source
Code for the Telinnovation Software. If the arbitrator determines that
Accelerated Networks is entitled to release of any Source Code, the arbitrator
shall further determine whether Accelerated Networks is entitled to the release
of all, or a portion of, the escrowed Source Code and shall order the release of
such Source Code. The prevailing party in the arbitration proceedings may, in
the arbitrator's discretion, be awarded reasonable costs, expenses, and
attorney's fees.

                           (d) Release of Source Code. If Escrow Agent does not
receive notification of any Telinnovation Dispute within seven days of receipt
of the Release Notification, Escrow Agent shall release the Source Code
specified in the Release Notification to Accelerated Networks. If Escrow Agent
does receive timely notification of a Telinnovation Dispute, Escrow Agent shall
release Source Code at such time as it receives (i) joint written direction from
Accelerated Networks and Telinnovation or (ii) an arbitration decision rendered
pursuant to section 3(c) and 10 of this Agreement and which directs the Escrow
Agent as to the disposition of the Source Code.

                           (e) Accelerated Networks Source Code License. In the
event that any Source Code is released to Accelerated Networks under the terms
of this section 3, Telinnovation shall retain all right title and interest to
such Source Code, and Accelerated Networks shall receive a nonexclusive,
perpetual and irrevocable, royalty-free, right and license (the "Source Code
License") to modify the Source Code for purposes of error correction,
maintenance,

                                       17
<PAGE>   19
support of and compatibility with updated operating systems, network protocols,
security procedures and the like.

                  4. Release of Source Code to Telinnovation. Upon termination
of this Agreement with respect to any Source Code in the Escrow Agent's
possession, the Escrow Agent is hereby directed to release such Source Code to
Telinnovation. Escrow Agent shall also release any Source Code to Telinnovation
upon (i) receipt of joint written direction from Telinnovation and Accelerated
Networks with respect to such Source Code or (ii) receipt of an arbitration
decision rendered pursuant to section 10 of this Agreement and which directs the
Escrow Agent as to the disposition of such Source Code.

                  5. Liability. The Escrow Agent shall be obligated to perform
only such duties as are expressly set forth in this Agreement. No implied
covenants or obligations shall be inferred from this Agreement against the
Escrow Agent. Escrow Agent does not have any interest in the Source Code
deposited hereunder but is serving as escrow holder only and has only possession
thereof.

                  The Escrow Agent shall not be liable hereunder except for its
own gross negligence or willful misconduct and Accelerated Networks and
Telinnovation agree to indemnify, hold harmless and defend Escrow Agent against
any claim or liability as to any loss, liability or expense, including attorney
fees, incurred without gross negligence or willful misconduct on the part of the
Escrow Agent and arising out of or in connection with this Agreement or Escrow
Agent's duties under this Agreement.

                  The Escrow agent shall be entitled to rely upon any order,
judgment, certification, instruction, notice or other writing delivered to it in
compliance with the provisions of this Agreement without being required to
determine the authenticity or the correctness of any fact stated therein or the
propriety or validity or service thereof. Escrow Agent may act in reliance upon
any instrument comporting with the provisions of this Agreement or signature
believed by it to be genuine and may assume that any person purporting to give
notice or receipt or advice or make any statement or execute any document in
connection with the provisions hereof has been duly authorized to do so.

                  The Escrow Agent may act pursuant to the advice of counsel
chosen by it with respect to any matter relating to this Agreement and shall not
be liable for any action taken or omitted in accordance with such advice.

                  6. Discharge of Escrow Agent. Escrow Agent agrees that
Accelerated Networks and Telinnovation may, by mutual agreement at any time,
remove Escrow Agent hereunder, and substitute another escrow agent therefore, in
which event, upon receipt of written notice thereof, Escrow Agent shall account
for and deliver to such substituted escrow agent the Source Code held by it, and
Escrow Agent shall thereafter be discharged from all liability under this
Agreement.

                  7. Term and Termination. Upon payment of the fees initially
due hereunder, this Agreement shall be in full force and shall have an initial
term of [one (1) year] unless earlier terminated (i) upon Escrow Agent's receipt
of written notice from Accelerated Networks and

                                       18
<PAGE>   20
Telinnovation or an arbitration decision stating that the Licensing Agreement
has been terminated; or (ii) on the date Escrow Agent receives written notice
from Accelerated Networks and Telinnovation terminating this Agreement. This
Agreement may be renewed for additional periods of [one (1) year] upon receipt
by Escrow Agent of the specified renewal fees prior to the last day of the term
(the "Expiration Date"). If Escrow Agent has not received the renewal fees
within thirty (30) days prior to the Expiration Date, Escrow Agent shall so
notify Accelerated Networks of the thirty (30) day expiration period. If the
renewal fees are not received within thirty (30) days after Accelerated
Networks' receipt of such written notice from Escrow Agent, Escrow Agent may
terminate this Agreement without further notice. Accelerated Networks shall have
the right to pay renewal fees and other related fees. Accelerated Networks may
extend the period of this Agreement to cover the processing of an outstanding
release instruction made during any period of this Agreement.

                  8. Escrow Fees. Telinnovation shall pay Escrow Agent all
applicable escrow fees as set forth in Exhibit B to this Agreement. Payment is
due upon receipt of invoice from Escrow Agent. All fees and charges are
exclusive of, and Telinnovation is responsible for the payment of, all sales,
use and like taxes. Escrow Agent shall have no obligations under this Agreement
until the initial invoice is paid in full by Telinnovation.

                  9. Proprietary Information; Nondisclosure. Escrow Agent
acknowledges and agrees that the Source Code contains information and data
proprietary to Telinnovation. Escrow Agent agrees to maintain all information
and data contained in the Source Code in strictest confidence for the benefit of
Telinnovation and Accelerated Networks. Escrow Agent agrees that it shall not
disclose, proliferate or duplicate any Source Code except as expressly allowed
in this Agreement. Escrow Agent shall ensure that any employee or agent
receiving a copy of the Source Code is fully apprised of the terms under which
Escrow Agent, its employees and agents may use the Source Code under this
Agreement.

                  10. Arbitration of Disputes. All disputes, or claims arising
out of, resulting from or related to this Agreement shall be finally settled
under the Rules of the American Arbitration Association (the "Rules") by an
arbitrator appointed in accordance with the Rules. If the parties fail to so
nominate a sole arbitrator within 30 days from the date when the claimant's
request for arbitration has been communicated to the other party, the sole
arbitrator shall be appointed in accordance with the Rules. Any decision made by
such an arbitrator within the scope of his or her authority shall be binding
upon the parties. The cost for such arbitrator shall be borne equally between
the parties, but all other costs involved in the arbitration shall be borne
separately by the parties. Each party shall enter into an arbitration agreement
providing reasonable protection to the arbitrator. The place of arbitration
shall be in Moorpark, California. Judgment on any award rendered by the
arbitrator may be entered by any court of competent jurisdiction.
Notwithstanding the forgoing, in the event of arbitration resulting from a
dispute concerning the release of Source Code, the provisions of this section 10
shall be modified by the terms of section 3(c) above.

                  11. Miscellaneous.

                           (a) Notices. All notices required or permitted to be
given hereunder shall be in writing and shall be deemed given when delivered in
person, by reputable overnight

                                       19
<PAGE>   21
courier service with tracking capabilities, or on the fifth business day after
being deposited in the mail, postage prepaid, registered or certified mail,
addressed as follows:

<TABLE>
<CAPTION>
         Telinnovation:                                        Accelerated Networks:
         -------------                                         --------------------
<S>                                                            <C>
         Telinnovation Service Corporation                     Accelerated Networks Corporation
         415 Clyde Avenue                                      301 Science Drive
         Suite 105                                             Moorpark, California  93021
         Mountain View, California  94035
         Escrow Agent:
</TABLE>

                  (b) Bankruptcy. Telinnovation and Accelerated Networks
acknowledge that this Agreement is an "agreement supplementary to" the License
Agreement and Development Agreement as provided in Section 365(n) of Title 11,
United States Code (the "Bankruptcy Code"). Telinnovation acknowledges that if
Telinnovation as a debtor in possession or a trustee in Bankruptcy in a case
under the Bankruptcy Code rejects the Licensing Agreement, Accelerated Networks
may elect to retain its rights under the Licensing Agreement and this Agreement
as provided in Section 365(n) of the Bankruptcy Code. Upon written request of
Accelerated Networks to Telinnovation or the Bankruptcy Trustee, Telinnovation
or such Bankruptcy Trustee shall not interfere with the rights of Accelerated
Networks as provided in the Licensing Agreement and this Agreement, including
the right to obtain the Source Code from the Escrow Agent.

                  (c) Expenses. Except as otherwise provided herein, Accelerated
Networks and Telinnovation shall be responsible for their own costs and expenses
with respect to matters involving this Agreement.

                  (d) Severability. If any provision of this Agreement is
determined by a court to be invalid or unenforceable, such determination shall
not affect any other provision, covenant, obligation or agreement, each of which
shall be construed and enforced as if such invalid or unenforceable portion were
not contained herein. Such invalidity or unenforceability shall not affect any
valid and enforceable application thereof, and each such provision, covenant,
obligation or agreement shall be deemed to be effective, to the full extent
permitted by law.

                  (e) Entire Agreement. This Agreement, including all exhibits
hereto, supersedes all prior discussions, understandings and agreements between
the parties with respect to the matters contained herein, and constitutes the
entire agreement between the parties with respect to the matters contemplated
herein.

                  (f) Multiple Counterparts. This Agreement may be executed in
two or more counterparts, each of which shall be deemed an original but all of
which together shall constitute one and the same instrument. This Agreement may
be signed and shall be deemed

                                       20
<PAGE>   22
delivered upon facsimile transmission of a signature in the space marked below,
but the parties shall endeavor to provide each other with originally signed
copies as soon as possible thereafter.

                  (g) Amendments and Waivers. This Agreement shall be binding
upon and inure to the benefit of the parties hereto and their respective
successors and assigns. No amendment or modification of this Agreement shall be
binding unless executed in writing by all parties hereto. No waiver of any of
the provisions of this Agreement shall be deemed to waive any other provision or
constitute a continuing waiver.

                  (h) Governing Law. This Agreement shall be governed by and
construed and enforced in accordance with the internal laws of the state of
California without giving effect to California's conflict of law rules.

                  (i) Independent Contractor. The parties acknowledge and agree
that the Escrow Agent is performing its functions under this Agreement as an
independent contractor and is not an employee or agent of Accelerated Networks
or Telinnovation.

                  (j) Survival. Sections 3(e), 5, 8, 9 and 11(b), and such
additional provisions of Section 11 as are necessary to give meaning and effect
to the foregoing shall survive any termination of this Agreement.

                                       21
<PAGE>   23
                  IN WITNESS WHEREOF, the parties hereto have signed this
Agreement as of the date first above-written.

                                        Telinnovation Service Corporation

                                        By     /s/
                                               ---------------------------------
                                               Its  Pres.
                                                    ----------------------------
                                        Accelerated Networks Corporation

                                        By     /s/
                                               ---------------------------------
                                               Its  President
                                                    ----------------------------

                                        ESCROW AGENT:

                                        By
                                               ---------------------------------
                                               Its
                                                    ----------------------------

                                       22
<PAGE>   24
                                    EXHIBIT A

                             TELINNOVATION SOFTWARE

                                       23
<PAGE>   25
                                    EXHIBIT B

                                   ESCROW FEES

                                       24
<PAGE>   26
                                    ADDENDUM

                      Account Number 2005139-00002-0103062

This is an Addendum to the attached Escrow Agreement dated December 24, 1998,
and among Accelerated Networks Corporation ("Accelerated Networks"),
Telinnovation Service Corporation ("Telinnovation"), and DSI Technology Escrow
Services ("Escrow Agent").

The parties acknowledge and agree to all the modifications set forth in the
following sections of this Addendum to the Escrow Agreement.

Section 1c., sentence 2 is hereby amended and restated to read as follows:

Any such deposit shall include Exhibit B a written description of the Source
Code identifying the software, version number, modifications from the previous
version and any other information required to uniquely identify the Source Code
(the "Deposit Description").

Section 1c., sentence 4 is hereby amended and restated to read as follows:

In the event the Source Code is damaged or destroyed in transit, Escrow Agent
shall notify Telinnovation within ten days of the receipt of such Source Code,
and Telinnovation shall deliver a duplicate copy of the Source Code to the
Escrow Agent within seven days of the receipt of such notice.

Section 1e., sentence 1 is hereby amended and restated to read as follows:

Upon deposit of the Source Code into the secure media vault, the Escrow Agent
shall notify Telinnovation and Accelerated Networks via First Class mail (the
"Deposit Notification").

Section 1e., sentence 2 is hereby amended and restated to read as follows:

The Deposit Notification shall include the date the Source Code was processed by
the Escrow Agent, and a copy of the Deposit Description.

Section 3a. is hereby amended and restated to read as follows:

(a)      Notification of Release Condition. Accelerated Networks will provide
         written notice to Escrow Agent and Telinnovation of the occurrence of
         any of the following conditions ("Release Notification");

Section 3d. is hereby amended and restated to read as follows

(d)      If Escrow Agent does not receive notification of any Telinnovation
         Dispute within seven days of Escrow Agent's receipt of the Release
         Notification, Escrow Agent shall release the Source Code specified in
         the Release Notification to Accelerated Networks. If Escrow Agent does
         receive notification of a Telinnovation Dispute within seven days of
         Escrow Agent's receipt of the Release Notification, Escrow Agent shall
         release Source Code at such time at it receives (i) joint written
         direction from Accelerated Networks and

                                       25
<PAGE>   27
Addendum
Accelerated Networks/Telinnovation
Page 2

         Telinnovation or (ii) an arbitration decision rendered pursuant to
         section 3(c) and 10 of this Agreement and which directs the Escrow
         Agent as to the disposition of the Source Code.

Section 11a.  is hereby amended and restated to read as follows:

Notices. All notices regarding the "Release of Deposit" will be sent out
certified mail, return receipt requested, or by commercial express mail. All
other notices, invoices, payments, deposits and other documents and
communications shall be given to the parties at the addresses specified in the
attached Exhibit C. It shall be the responsibility of the parties to notify each
other as provided in this Section in the event of a change of address. The
parties shall have the right to rely on the last known address of the other
parties. Unless otherwise provided in this Agreement, all documents and
communications may be delivered by First Class mail.

Agreed:
Accelerated Networks                             Telinnovation

By:    /s/Suresh Nihalani                        By:    /s/Charles R. Davis
       ---------------------------------                ------------------------
Name:  Suresh Nihalani                           Name:  Charles R. Davis
       ---------------------------------                ------------------------
Title:   President & CEO                         Title:  Pres
       ---------------------------------                ------------------------
Date:    1-29-99                                 Date:  2-11-99
       ---------------------------------                ------------------------

DSI Technology Escrow Services

By:    /s/[illegible]
       ---------------------------------
Name:
       ---------------------------------
Title:   Sr. Contract Administrator
       ---------------------------------
Date:    2-3-99
       ---------------------------------

                                       26
<PAGE>   28

SCHEDULE E - SERVICE STANDARDS

If the Technology fails to conform to the specifications therefor, the Developed
Technology or any component thereof fails to conform to the Developed Technology
Specifications, of the Technology or the Developed Technology is defective in
material or workmanship, Telinnovation shall correct any such non-conformance or
defect and deliver the Developed Technology to Accelerated Networks for all
affected End User sites. The initial determination of priority, as described
below, shall be made solely by Accelerated Networks, in its reasonable
discretion. Telinnovation shall respond to failures of Technology or Developed
Technology to operate as warranted as follows:

PRIORITY 1. A "Priority 1" failure of the Technology or Developed Technology to
operate as warranted is any condition that precludes operation of the Technology
or Developed Technology as bundled with or incorporated into a Product, or that
materially impairs such operation. Priority 1 conditions are the highest in
severity, for which Accelerated Networks shall receive a response within one (1)
business day from the time (the "Notification Time") Telinnovation's service
representative ("SR") or other person receives the call from Accelerated
Networks notifying the SR of the Priority 1 failure. Telinnovation shall use its
best efforts to resolve and correct a Priority 1 failure in a manner reasonably
acceptable to Telinnovation within two (2) business days from the Notification
Time.

PRIORITY 2. Any condition that impairs one or more functions of the Technology
or Developed Technology is warranted to perform, but that does not involve a
Priority 1 condition and is not a Priority 3 condition, is a "Priority 2"
condition. Priority 2 conditions are less severe than Priority 1 conditions. For
Priority 2 conditions, Accelerated Networks shall receive a response within one
(1) business day from the Notification Tune. Telinnovation shall use its best
efforts to resolve and correct a Priority 2 failure in a manner reasonably
acceptable to Accelerated Networks within three (3) business days from the
Notification Time.

PRIORITY 3. Any condition that constitutes an immaterial, defect or error in one
or more functions that the Technology or Developed Technology is warranted to
perform is a "Priority 3" condition. Priority 3 conditions are the least severe.
For Priority 3 conditions, the Accelerated Networks shall receive a response
within two (2) business days from the Notification Time. Telinnovation shall use
reasonable efforts to resolve and correct a Priority 3 failure in a manner
reasonably acceptable to Accelerated Networks within three (3) weeks from the
Notification Time.

If Telinnovation is unable to correct a Priority 1 or Priority 2 condition
within ten (10) business days, or a Priority 3 condition within one (1) month,
of the date on which the SR or other person receives the call informing
Telinnovation of the Priority 1, Priority 2, or Priority 3 condition, as the
case may be, Accelerated Networks may, in its sole discretion, withhold payment
of any amount due under Agreement until the condition is corrected. If
Telinnovation is unable to correct a Priority 1 or Priority 2 condition within
such ten (10) business-day period, or in the event of a Priority 3 condition
such one (1) month period, despite Telinnovation's diligent efforts to do so,
then Telinnovation shall continue to use its diligent efforts to correct the
condition as soon as practicable. In the event Telinnovation fails to exercise
such diligent efforts as reasonably determined by Accelerated Networks,
Accelerated Networks shall be entitled to (a)

                                       27
<PAGE>   29

immediately terminate the Agreement without any further obligation to
Telinnovation, (b) exercise Accelerated Networks' right to obtain source code
under Section and/or (iii) exercise any other remedy available at law, in
equity, by statute, or otherwise.

                                       28
<PAGE>   30

             Amendment I to License Agreement dated December 1998.

The first two sentences of ARTICLE 8.1 of The License Agreement between
Accelerated Networks Corporation and Telinnovation Service Corporation dated
December 1998 are as follows:

8.1  This Agreement shall remain in full force and effect for a period of one
     (1) year from the Effective Date. Thereafter, this Agreement shall
     automatically renew for successive terms of one (1) year each, unless, at
     least (30) days prior to the end of the then-current term, one party
     provides the other party with written notice of such party's intention to
     terminate this Agreement.

These sentences are amended as follows

8.1  This Agreement shall remain in full force and effect for a period of three
     (3) years from the Effective Date. Thereafter, this Agreement shall
     automatically renew for successive terms of three (3) years each, unless,
     at least (90) days prior to the end of the then-current term, one party
     provides the other party with written notice of such party's intention to
     terminate this Agreement.

In witness whereof, the parties have signed this Amendment on the dates given:

TELINNOVATION SERVICE CORP.                ACCELERATED NETWORKS CORP.

By:     /s/ Charles R. Davis               By:   /s/ Frederic T. Boyer
        ------------------------------           -------------------------------

Name:       Charles R. Davis               Name:    Frederic T. Boyer
            --------------------------              ----------------------------

Title:      President                      Title:   Chief Financial Officer
            --------------------------              ----------------------------

Date:       1/29/00                        Date:    1/29/00
            --------------------------              ----------------------------

                                                                              29<PAGE>   1
                                                                Exhibit 10.28

                       PRODUCT PURCHASE AND SALE AGREEMENT

        This Product Purchase and Sale Agreement ("Agreement"), effective as of
        February 23, 2000 (the "Effective Date"), is made by and between
        Accelerated Networks, Inc., a California corporation with its principal
        place of business at 301 Science Drive, Moorpark CA, 93021 ("SELLER")
        and UniDial Communications, Inc. with its principal place of business
        1901 East Point Parkway, Louisville, KY 40223 ("CUSTOMER"). CUSTOMER AND
        SELLER are also referred to collectively as the "Parties." The Parties
        agree as follows:

1.      PRODUCT ORDERS

1.1     Purchase Order. On the effective date of this agreement, CUSTOMER will
        submit a purchase order for SELLER's products described in Attachment A
        ("Products") having an aggregate purchase price of at least $10,000,000
        (the "Purchase Order"). Delivery dates will be [***] in calendar ---
        Quarter One of 2000 and [***] in Quarters Two, Three and Four ---
        respectively. CUSTOMER may apply overage purchases to the following
        Quarter's commitment level. CUSTOMER may specify the carrier and mode of
        transportation for shipment of Product. Terms and conditions contained
        in any purchase order, confirmation, invoice, acknowledgment, release,
        acceptance or other written correspondence will not only modify any of
        the terms of this Agreement and the terms of this shall be controlling
        over any inconsistent or conflicting terms.

1.2     Subsequent Purchase Orders. During the term of this Agreement, CUSTOMER
        may submit purchase orders in addition to the Purchase Order described
        in Section 1.1. The terms of this Agreement shall apply to all such
        additional purchase orders.

1.3     Submission of Orders. All purchase orders shall be sent by fax to the
        following address:

        Accelerated Networks
        301 Science Drive
        Moorpark, CA 93021
        Attn: Sales Administration
        Fax (805) 553-9696

1.4     Purchase Order Cancellation, Rescheduling and Alterations. CUSTOMER may
        cancel delivery of Products pursuant to a purchase order without charge
        upon written notice to SELLER not less than [***] prior to the scheduled
        delivery date. CUSTOMER will be responsible for payment of one hundred
        percent (100%) of the amount of any portion of a purchase order that is
        canceled less than [***] prior to the scheduled delivery date. CUSTOMER
        may reschedule delivery date of Products pursuant to a purchase order
        without charge upon written notice to SELLER not less than [***] prior
        to the scheduled delivery date. This reschedule of delivery of Products
        by SELLER can only be done two (2) times per purchase order and the
        revised delivery date cannot be greater than [***] from the originally
        scheduled delivery date. CUSTOMER may alter a purchase order with a
        written purchase order change notice to SELLER not less than [***] prior
        to the scheduled delivery date. Alterations would include (i) change a
        location for delivery, (ii) modify the quantity or type of Products to
        be delivered or (iii) correct typographical or clerical errors.

*** Confidential treatment has been requested for certain redacted provisions of
this agreement. The redacted provisions are identified by three asterisks
enclosed by brackets and underlined. The confidential portion has been filed
separately with the Securities and Exchange Commission.

                                       1
<PAGE>   2

1.5     Pricing. Product prices payable by the CUSTOMER and applicable discounts
        are set forth in Attachment B. Prices are exclusive of all taxes,
        customs duties or similar tariffs and fees, shipping and insurance
        charges which SELLER may be required to pay or collect upon the sale or
        delivery of the Products or upon collection of the sales price, all of
        which shall be CUSTOMER's responsibility.

1.6     Payment. Terms of payment are net thirty (30) days of SELLER's invoice
        date, unless SELLER at any time determines that CUSTOMER's credit is not
        satisfactory, in which case payment terms shall be, at SELLER's
        election, C.O.D., in advance of delivery or by irrevocable letter of
        credit in favor of SELLER. All payments shall be made in U.S. dollars in
        the United States.

2.      DELIVERY AND ACCEPTANCE

2.1     Delivery. Products are delivered FOB SELLER's plant or other place of
        shipment. Shipments will be made to the delivery address specified on
        CUSTOMER's purchase order. In the absence of a specified delivery
        address, delivery will be made to CUSTOMER's Louisville facility.
        Shipping arrangements will be mutually agreed upon by the Parties prior
        to delivery. SELLER shall use its commercially reasonable efforts to
        fill (by full or partial shipment) CUSTOMER's purchase orders for
        Products within [***] of receiving purchase order.

2.2     Inspection and Acceptance of Deliveries. CUSTOMER shall have the right
        to visually inspect all Products ordered pursuant to this Agreement for
        a period of [***] following delivery. If the delivered Product(s) fails
        to conform to the applicable purchase order or release, in whole or in
        part, CUSTOMER may reject the delivery and CUSTOMER shall promptly
        return the rejected Product(s) to SELLER at SELLER's risk and expense.
        Upon receipt of the rejected Product(s), SELLER will promptly ship
        replacement Product(s) to CUSTOMER.

2.3     Pre-shipment Review. If reasonably requested by CUSTOMER, a
        representative of CUSTOMER may participate, to the extent applicable, in
        SELLER's preshipment configuration, prestaging and inspection of Product
        at SELLER's facility.

3.      SOFTWARE LICENSE

3.1     License Grant. SELLER grants CUSTOMER, subject to the terms and
        conditions set forth in this Agreement, a non-exclusive,
        non-transferable, non-sublicenseable license to (i) use the software
        comprising any Product (including software contained in firmware
        embedded in a Product) ("Software") and (ii) distribute the Software to
        CUSTOMER's end-user customers together with SELLER's standard End User
        Software License Agreement in conjunction with CUSTOMER's product and
        service offerings. All copies of the Software are licensed and not sold.
        As between the Parties, SELLER retains all title to (except as expressly
        licensed by SELLER)s, and rights (including all intellectual property
        and proprietary rights anywhere in the world) and interest in the
        Software.

3.2     License Regulations. CUSTOMER shall not, nor permit others to (i) copy,
        modify or create any derivative work of the Software or include the
        Software in any other software (ii) delete, alter or obscure any
        copyright or other notice or proprietary legend appearing in the
        Software or on any documentation, media, master or package materials for
        the Software provided by SELLER or (iii) reverse assemble, decompile,
        reverse engineer or otherwise attempt to derive the source code (or the
        underlying ideas, structure, sequence, organization or algorithms) from
        the Software.

4.      MONTHLY MEETINGS. SELLER and CUSTOMER shall each designate at least one
        representative to serve as a liaison with the other party (each a
        "Representative"). The Representatives shall meet, either in person or
        by telephone, to discuss in good faith matters relating to this
        Agreement including Product delivery schedules, joint marketing
        activities, sales training needs, price changes and new Product features
        and

*** Confidential treatment has been requested for certain redacted provisions of
this agreement. The redacted provisions are identified by three asterisks
enclosed by brackets and underlined. The confidential portion has been filed
separately with the Securities and Exchange Commission.

                                       2
<PAGE>   3

        enhancements. Such meetings shall take place on a monthly basis at a
        mutually agreed upon location. Each party shall bear its own costs
        incurred in attending or participating in such meetings.

5.      SELLER'S WARRANTY

5.1     Product Warranty. SELLER warrants to CUSTOMER (i) for a period of one
        (1) year from the date of shipment, that the hardware Products will be
        free from material defects in materials and workmanship, (ii) for a
        period of ninety (90) days from the date of shipment, the Software will
        perform substantial in accordance with applicable specifications
        identified in the user manual of the then current release and (iii)
        services performed by SELLER hereunder will be performed in a
        professional and workmanlike manner and in accordance with current
        industry standards. SELLER's warranty does not extend to any Product
        that (a) is modified or altered, (b) is not maintained to SELLER's
        maintenance recommendations (c) is operated in a manner other than that
        specified by SELLER, (d) has its serial number removed or altered or (e)
        is treated with abuse, negligence or other improper treatment
        (including, without limitation, use outside the recommended
        environment).

5.2     Remedies. Products delivered to CUSTOMER by SELLER hereunder which do
        not comply with the warranty in Section 5.1 above and are returned to
        SELLER during the applicable warranty period will be repaired or
        replaced at SELLER's option at no cost to CUSTOMER. If SELLER cannot, or
        determines that it is not practical to, repair or replace a returned
        Product, the price paid by CUSTOMER for such Product will be credited
        and applied to future orders.

5.3     Disclaimer. SELLER MAKES NO WARRANTIES (OTHER THAN AS EXPRESSLY PROVIDED
        IN SECTION 5.1 ABOVE) WITH RESPECT TO THE PRODUCTS, OR ANY SERVICES AND
        DISCLAIMS ALL OTHER WARRANTIES, EXPRESS OR IMPLIED, INCLUDING WARRANTIES
        OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
        NON-INFRINGEMENT. FURTHER, SELLER DOES NOT WARRANT THE USE, OR THE
        RESULTS OF THE USE, OF THE PRODUCTS OR THAT ANY SOFTWARE WILL BE
        ERROR-FREE.

5.4     Year 2000 Compliance Warranty. Seller represents and warrants the ("Year
        2000 Warranty') that (a) all Calendar-Related processing by the Products
        and Special Products of Date Data or of any System Date will not cause
        the Products to cease to operate substantially in accordance with the
        Specifications, (b) all data fields for the Date Data contained in the
        Products are four-digit fields capable of indicating century and
        millennium, and (c) that Seller has verified through its testing
        procedures that no change in the System Date (including the changes from
        the year 1999 to the year 2000) will cause the Products or the Special
        Products to cease to operate substantially in accordance with their
        Specifications. Notwithstanding any provision to the contrary set forth
        in this Agreement, Seller makes no representation or warranty with
        respect to the Products or Special Products operating in conjunction
        with any computer software, computer firmware, computer hardware, or any
        combination of the foregoing supplied by third parties.

6.      CUSTOMER'S REPRESENTATIONS AND WARRANTIES. CUSTOMER represents, warrants
        and covenants that (i) it shall comply with good business practices and
        all laws and regulations relevant to this Agreement or the subject
        matter hereof, (ii) it shall use the then current names used by SELLER
        for the Products provided that all advertisements, promotional
        materials, packaging and anything else bearing any trademark of SELLER's
        shall identify SELLER as the trademark owner and shall be subject to
        SELLER's prior written approval and (iii) shall comply with all export
        laws, restrictions, national security controls and regulations of the
        United States or other applicable foreign agency or authority, and not
        to export or re-export, or allow the export or re-export of any Product
        or Proprietary Information of SELLER or any direct product thereof in
        violation of any such restrictions, laws or regulations, or without all
        required licenses and proper authorizations, any Group D-I or E-2
        country (or national of such country) specified in the then current U.S.
        Export Administration Regulations (or any successor supplement or
        regulations).

7.      LIMITATION OF LIABILITY.  NEITHER PARTY WILL BE LIABLE WITH RESPECT TO
        ANY SUBJECT MATTER OF THIS AGREEMENT UNDER ANY CONTRACT, NEGLIGENCE,
        STRICT LIABILITY OR OTHER LEGAL OR EQUITABLE THEORY FOR (I) ANY AMOUNTS
        IN EXCESS IN THE AGGREGATE OF THE AMOUNTS PAID TO IT (IN THE CASE OF
        SELLER) OR (IN THE CASE OF

                                       3
<PAGE>   4

        CUSTOMER) PAID OR OWED BY IT HEREUNDER DURING THE TWELVE (12)-MONTH
        PERIOD PRIOR TO DATE THE CAUSE OF ACTION AROSE OR (II) ANY INCIDENTAL OR
        CONSEQUENTIAL DAMAGES, LOST PROFITS OR LOST DATA OR (III) COST OF
        PROCUREMENT OF SUBSTITUTE GOODS, TECHNOLOGY OR SERVICES. THE LIMITATIONS
        OF THIS SECTION 7 SHALL NOT APPLY TO ANY BREACH OF SECTION 3.2 OR 9.

8.      RELATIONSHIP OF THE PARTIES. CUSTOMER expressly acknowledges that it is
        an independent contractor in the performance of this Agreement, and is
        solely liable for all labor and related expenses in connection with this
        Agreement. CUSTOMER will not have, and will not represent that it has,
        any power, right or authority to bind SELLER, or to assume or create any
        obligation or responsibility, express or implied, on behalf of SELLER.

9.      PROPRIETARY INFORMATION. The Parties acknowledge that in the course of
        performing their duties under this Agreement, each may obtain
        confidential and proprietary information of the other ("Proprietary
        Information"). Such Proprietary Information may include, but is not
        limited to, trade secrets, know-how, inventions, techniques, processes,
        programs, schematics, software source code, data, customer lists,
        financial information, and sales and marketing plans. Each party shall
        at all times keep in trust and confidence all Proprietary Information of
        the other party and, during the term of this Agreement and for five (5)
        years after its termination, shall not use such Proprietary Information
        other than in the course of performing its duties under this Agreement
        nor shall it disclose any such Proprietary Information to any third
        party without the written consent of the other. Upon termination or
        expiration of this Agreement or upon the request of the disclosing
        party, each party shall promptly return all manifestations of the
        other's Proprietary Information in its possession.

10.     TERM AND TERMINATION.

10.1    Term. This Agreement shall commence on the Effective Date and shall
        remain in force for a period of One (1) year unless earlier terminated
        as provided in this Section 10. Thereafter, this Agreement shall
        automatically renew for successive one (1)-year terms unless a party
        provide written notice to the other party no later than sixty (60) days
        prior to the expiration of the then current terms of such party's intent
        not to renew.

10.2    Termination for Convenience. This Agreement may be terminated at any
        time, with or without cause, by either party upon ninety (90) days prior
        written notice to the other party.

10.3    Termination for Cause. This Agreement may be terminated by either party
        for cause immediately by written notice upon the occurrence of any of
        the following events: (i) if the other ceases to do business, or
        otherwise terminates its business operations, provided, however, that
        the acquisition of all or substantially all of a party's stock, assets
        or business shall not be grounds for termination of this Agreement; or
        (ii) if the other breaches any material provision of this Agreement and
        fails to cure such breach within thirty (30) days of written notice
        describing the breach; provided, however, that a breach of the
        obligations set forth in Section 3.2 or 9 and shall be grounds for
        immediate termination of this Agreement by the non-breaching party, or
        (iii) if the other becomes insolvent or seeks protection under any
        bankruptcy, receivership, trust deed, creditors arrangement, composition
        or comparable proceeding, or if such proceeding is instituted against
        the other (and not dismissed within ninety (90) days).

10.4    Effect of Termination. Upon any termination or expiration of this
        Agreement, all pending purchase orders for release of Products shall be
        canceled as of the effective date of termination or expiration, all sums
        payable to SELLER shall be due and payable on the effective date of
        termination of expiration and all licenses granted to CUSTOMER under
        this Agreement shall immediately terminate, and CUSTOMER shall
        discontinue all use and distribution of the Products. Upon an end-user
        acquiring a copy of the Software pursuant to an End-User License
        Agreement, the end-user shall be entitled to use that copy of the
        Software, subject to the terms and conditions of the End-User License
        Agreement.

11.     PUBLICITY. The Parties shall announce this Agreement and the
        establishment of the relationship between CUSTOMER and SELLER under this
        Agreement pursuant to a joint press release to be mutually agreed

                                       4
<PAGE>   5

        upon. The Parties agree to submit to each other for approval all other
        press releases relating to this Agreement and to not publish any press
        release without prior approval of the other party, which approval shall
        not be unreasonably withheld.

12.     ASSIGNMENT. This Agreement shall be binding on successors and assigns
        provided, however, this Agreement may not be assigned or transferred by
        CUSTOMER without the prior written consent of the SELLER, which consent
        shall not be unreasonably withheld. Any purported assignment in
        violation of this Section 12 shall be null and void.

13.     MISCELLANEOUS

13.1    No Waiver. A waiver by either party of any provision of this Agreement
        or breach, in any one instance, shall not be construed as a waiver of
        any other provision or subsequent breach thereof.

13.2    Notices. All notices or communications of any kind made or required to
        be given pursuant to this Agreement shall be in writing and delivered by
        personal service to the other party or sent by first class mail, postage
        prepaid to the address for such party specified in this first paragraph
        of this Agreement or such other address as such party shall provide
        notice of in accordance with this Section 13.2.

13.3    Governing Law Legal Actions. This Agreement shall be governed and
        construed under California law, without regard to conflicts of laws
        provisions thereof. Any controversy, claim or dispute between the
        parties to this Agreement arising out of, in connection with, or in
        relation to the interpretation, validity, performance or breach of this
        Agreement shall, at the request of either party, be resolved to the
        exclusion of a court of law by binding arbitration in Ventura County,
        California, in accordance with the Commercial Arbitration Rules of the
        American Arbitration Association then in effect (but. nonetheless the
        arbitration itself shall not be conducted under the auspices of such
        Association unless the parties shall expressly so agree). The
        arbitrator(s) shall be empowered to award relief which is legal and/or
        equitable in nature, as appropriate. Except to the extent expressly
        contradicted by the Commercial Arbitration Rules of the American
        Arbitration Association and/or this Agreement, the arbitration
        provisions of Section 1280 et seq. (Part 3, Title 9) (with the exception
        of Section 1283.05) of the California Code of Civil Procedure shall be
        fully applicable to this Agreement. For purposes of California Code of
        Civil Procedure Section 1281.8 (relating to court issuance of
        provisional remedies), the parties agree that in any controversy, claim
        or dispute involving the Proprietary Information section of this
        Agreement and/or the protection of any intellectual property, it shall
        be conclusively presumed, if a party is otherwise entitled to have a
        court issue a provisional remedy, that the arbitration award to which
        the party may be entitled may be rendered ineffectual without
        provisional remedy.

13.4    Severability. If any provisions of this Agreement is held by a court of
        competent jurisdiction to be illegal, invalid or unenforceable, that
        provision shall be limited or eliminated to the minimum extent necessary
        so that this Agreement shall otherwise remain in full force and effect
        and enforceable.

13.5    Force Majeure. A party shall not be liable for non-performance or delay
        in performance (other than of payment or confidentiality obligations)
        caused by any event reasonably beyond the control of such party
        including, but not limited to wars, hostilities, revolutions, riots,
        civil commotion, national emergency, strikes, lockouts or other labor
        disputes or shortages or inability to obtain material or equipment,
        unavailability of supplies, compliance with laws or regulation
        (including, without limitation, those related to infringement),
        epidemics, fire, flood, earthquake, force of nature, explosion, embargo,
        or any Act of God, or any law, proclamation, regulation, ordinance or
        other act or order of any court, government or governmental agency.

13.6    Entire Agreement Amendment. This Agreement, including all Attachments to
        this Agreement, constitutes the entire agreement between the parties
        relating to the subject matter hereof and all prior or simultaneous
        proposals, negotiations, representations, conversations, discussions and
        agreements, whether written or oral, among the parties and all past
        dealing or industry custom. This Agreement may not be amended except by
        a writing signed by the Parties.

                                       5
<PAGE>   6

13.7    This Agreement may be executed in two or more counterparts, each of
        which shall be deemed an original, but all of which together shall
        constitute one and the same instrument.

IN WITNESS WHEREOF, the Parties hereto have executed this Agreement effective as
the Effective Date.

By:  /s/ Suresh Nihalani                   By:  /s/ Michael Johnson
     --------------------------------           --------------------------------
Name:  Suresh Nihalani                     Name:  Michael Johnson
       ------------------------------             ------------------------------
Title:    President and CEO                Title:    CTO
       ------------------------------             ------------------------------
Date:    March 17, 2000                    Date:    February 23, 2000
       ------------------------------             ------------------------------

                                       6
<PAGE>   7

                                   ATTACHMENT A
<TABLE>
<CAPTION>
--------------------------------------------------------------------------------
Products                         Description
--------------------------------------------------------------------------------
<S>                      <C>
AN-3220                  AN-3200 20-slot 23" Chassis. - 48 VDC power
--------------------------------------------------------------------------------
SYSMOD1-DS3-2            System Combo Card includes system processor, 1-port
                         Ethernet 10/100TX, 1 console port. 2 PREINSTALLED DS-3
                         (45MBPS) ATM WAN UPLINK DAUGHTERCARDS.
--------------------------------------------------------------------------------
LC12-T1                  12-channel line card supports ATM over unchannelized
                         T1.12 integral T1 modems with CSU/DSU on daughtercards.
--------------------------------------------------------------------------------
VSIC-8TC                 8-channel T1 and Voice Server Card with hardware
                         support for voice compression. 8DS-1 channelized T1
                         digital voice interfaces for connection to PBX or Class
                         5 switches. Supports 192 channels of G.711 PCM or 96
                         voice channels of voice compression. Supports G.168
                         echo cancellation and structured CES service via CBR
                         voice over AAL1 and rtVBR voice over AAL2. Hardware
                         ready for G.726. Software for compression is sold
                         separately. REQUIRES MULTI-SERVICE GATEWAY SYSTEM
                         SOFTWARE.
--------------------------------------------------------------------------------
MSAP-SW-GW2.2            Multi-Service Gateway System software version 2.2.
                         Required with any purchase of voice module with MSAP
                         unit.
--------------------------------------------------------------------------------
MSAP-SW-VCMP3.0          G.726 Voice compression software for 96 voice channels
                         Voice Server Card. THIS OPTION MUST BE PURCHASED FOR
                         EACH VOICE SERVER CARD THAT NEEDS VOICE COMPRESSION.
--------------------------------------------------------------------------------
AP v2.4                  Access Pilot EMS S/W support 50 fully loaded MSAPs.
--------------------------------------------------------------------------------
AN-30T                   Integrated Access Device Base Unit. 1-port Ethernet
                         10/100TX, 2-ports Serial V.35/V.11(Slimline 26
                         connectors), 1-port ATM WAN over unchannelized T1 up to
                         1.544Mbps with built-in CSU/DSU, and 1-slot for factory
                         installed Voice Interface Module. Includes manual,
                         Ethernet cable, and SDSL cable. REQUIRES SLIMLINE 26
                         CONNECTOR TO V.35 SERIAL CABLE (CDXEXXX-XX), PLEASE
                         REFER TO THE CABLING SECTION OF THE PRICE LIST FOR
                         ORDERING OPTIONS. REQUIRES A CONFIGURATION WORKSHEET
                         WITH EVERY ORDER.
--------------------------------------------------------------------------------
AN-30VM-D24C             Digital Voice Module for AN-30. 24-DS0 digital voice
                         channels with 2-ports T1 for drop & insert
                         functionality. Hardware supports G.711 PCM and G.168
                         echo cancellation. Hardware ready for voice compression
                         requirements. Software for compression is sold
                         separately.
--------------------------------------------------------------------------------
AN-30-SW-DCMP3.0         G.726 ADPCM voice compression software for 24-ports
                         digital voice module.
--------------------------------------------------------------------------------
AN-30-SW-DSS2.2          Dynamic Service Selection Software for the AN-30 IAD.
--------------------------------------------------------------------------------
AN-30-SW-B2.2            Basic System Software version 2.2 for the AN-30 IAD.
                         W/routing.
--------------------------------------------------------------------------------
AN-20T                   Integrated Access Device Base Unit. Includes 1-port
                         Ethernet 10BT and 1-port ATM WAN over unchannelized T1
                         (integral CSU/DSU).
--------------------------------------------------------------------------------
AN-20-SW-B2.2            Basic System Software version 2.2 for the AN-20 IAD.
                         W/routing.
--------------------------------------------------------------------------------
AN-20-SW-DSS2.2          Dynamic Service Selection Software version 2.2 for the
                         AN-20 IAD.
--------------------------------------------------------------------------------
</TABLE>

                                      A-1
<PAGE>   8

                                  ATTACHMENT B
                       PRODUCT PRICES AND DISCOUNT LEVELS

SHIPMENT SCHEDULE FOR Q1/2000:
<TABLE>
<CAPTION>
------------------------------------------------------------------------------------------------------------------------------------
<S>        <C>     <C>                  <C>                                                   <C>        <C>          <C>
LINE        QTY         MODEL NO.                          DESCRIPTION                         LIST      DISCOUNT      DISCOUNT
ITEM                                                                                          PRICE        RATE          PRICE
------------------------------------------------------------------------------------------------------------------------------------
    1      [***]   AN-3220              AN-3200 20-slot 23" Chassis. - 48 VDC power.         $ 7,995        [***]        [***]
            ---                                                                                  ---         ---          ---
------------------------------------------------------------------------------------------------------------------------------------
    2      [***]   SYSMOD1-DS3-2        System Combo Card includes system processor,         $ 7,085        [***]        [***]
            ---                         1-port Ethernet 10/100TX, 1 console port.  2             ---         ---          ---
                                        PREINSTALLED DS-3 (45MBPS) ATM WAN UPLINK
                                        DAUGHTERCARDS.
------------------------------------------------------------------------------------------------------------------------------------
    3      [***]   LC12-T1              12-channel line card supports ATM over               $ 8,995        [***]        [***]
            ---                         unchannelized T1.12 integral T1 modems with              ---         ---          ---
                                        CSU/DSU on daughtercards.
------------------------------------------------------------------------------------------------------------------------------------
    4      [***]   VSIC-8TC             8-channel T1 and Voice Server Card with hardware     $18,995        [***]        [***]
            ---                         support for voice compression. 8 DS-1                    ---         ---          ---
                                        channelized T1 digital voice interfaces
                                        for connection to PBX or Class 5
                                        switches. Supports 192 channels of G.711
                                        PCM or 96 voice channels of voice
                                        compression. Supports G.168 echo
                                        cancellation and structured CES service
                                        via CBR voice over AAL1 and rtVBR voice
                                        over AAL2. Hardware ready for G.726.
                                        Software for compression is sold
                                        separately. REQUIRED MULTI-SERVICE
                                        GATEWAY SYSTEM SOFTWARE.
------------------------------------------------------------------------------------------------------------------------------------
    5      [***]   MSAP-SW-GW3.0        Multi-Service Gateway System software version 3.0    $ 4,995        [***]        [***]
            ---                         Required with any purchase of voice                      ---         ---          ---
                                        module with MSAP unit.
------------------------------------------------------------------------------------------------------------------------------------
    6      [***]   MSAP-SW-VCMP3.0      G.726 Voice compression software for 96 voice        $ 2,995        [***]        [***]
            ---                         channels Voice Server Card.                              ---         ---          ---
                                        THIS OPTION MUST BE PURCHASED FOR EACH
                                        VOICE SERVER CARD THAT NEEDS VOICE
                                        COMPRESSION.
------------------------------------------------------------------------------------------------------------------------------------
    7      [***]   AP v2.4              Access Pilot EMS S/W support 50 fully loaded MSAPs   $ 9,995        [***]        [***]
            ---                                                                                  ---         ---          ---
------------------------------------------------------------------------------------------------------------------------------------
</TABLE>

<TABLE>
<CAPTION>
---------------
<S>             <C>
EXTENDED PRICE

---------------
    [***]
     ---
---------------
    [***]
     ---

---------------
    [***]
     ---

---------------
    [***]
     ---

---------------
    [***]
     ---

---------------
    [***]
     ---

---------------
    [***]
     ---
---------------
</TABLE>

*** Confidential treatment has been requested for certain redacted provisions of
this agreement. The redacted provisions are identified by three asterisks
enclosed by brackets and underlined. The confidential portion has been filed
separately with the Securities and Exchange Commission.

                                      B-1
<PAGE>   9
<TABLE>
<CAPTION>
------------------------------------------------------------------------------------------------------------------------------------
  LINE      QTY         MODEL NO.                          DESCRIPTION                     LIST        DISCOUNT       DISCOUNT
  ITEM                                                                                     PRICE         RATE           PRICE
------------------------------------------------------------------------------------------------------------------------------------
<S>        <C>      <C>                 <C>                                              <C>           <C>           <C>
    8      [***]   AN-30T               Integrated Access Device Base Unit.  1-port        $2,395        [***]        [***]
            ---                         Ethernet 10/100TX, 2-ports Serial                     ---         ---          ---
                                        V.35/V.11 (Slimline 26 connectors),
                                        1-port ATM WAN over unchannelized T1 up
                                        to 1.544 Mbps with built-in CSU/DSU, and
                                        1-slot for factory installed Voice
                                        Interface Module. Includes manual,
                                        Ethernet cable, and SDSL cable. REQUIRES
                                        SLIMLINE 26 CONNECTOR TO V.35 SERIAL
                                        CABLE (CDXEXXX-XX), PLEASE REFER TO THE
                                        CABLING SECTION OF THE PRICE LIST FOR
                                        ORDERING OPTIONS. REQUIRES A
                                        CONFIGURATION WORKSHEET WITH EVERY
                                        ORDER.
------------------------------------------------------------------------------------------------------------------------------------
    9      [***]   AN-30VM-D24C         Digital Voice Module for AN-30.  24-DS0 digital    $3,600        [***]        [***]
            ---                         voice channels with 2-ports T1 for drop               ---         ---          ---
                                        & insert functionality. Hardware
                                        supports G.711 PCM and G.168 echo
                                        cancellation. Hardware ready for voice
                                        compression requirements. Software for
                                        compression is sold separately.
------------------------------------------------------------------------------------------------------------------------------------
   11      [***]   AN-30-SW-DCMP3.0     G.726 ADPCM voice compression software for         $  695        [***]        [***]
            ---                         24-ports digital voice module.                        ---         ---          ---
------------------------------------------------------------------------------------------------------------------------------------
   12      [***]   AN-30-SW-DSS2.2      Dynamic Service Selection Software for the AN-30   $  300        [***]        [***]
            ---                         IAD.                                                  ---         ---          ---
------------------------------------------------------------------------------------------------------------------------------------
   13      [***]   AN-30-SW-B3.0        Basic System Software version 2.2 for the AN-30         0        [***]        [***]
            ---                         IAD. W/routing                                        ---         ---          ---

------------------------------------------------------------------------------------------------------------------------------------
   14      [***]   AN-20T               Integrated Access Device Base Unit.  Includes      $  895        [***]        [***]
            ---                         1-port Ethernet 10BT and 1-port ATM WAN               ---         ---          ---
                                        over unchannelized T1 (integral
                                        CSU/DSU).
------------------------------------------------------------------------------------------------------------------------------------
   15      [***]   AN-20-SW-B2.2        Basic System Software version 2.2 for the AN-20         0        [***]        [***]
            ---                         IAD. W/routing.                                       ---         ---          ---

------------------------------------------------------------------------------------------------------------------------------------
   16      [***]   AN-20-SW-DSS2.2      Dynamic Service Selection Software version 2.2     $  200        [***]        [***]
            ---                         for the AN-20 IAD.                                    ---         ---          ---

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

</TABLE>

<TABLE>
<CAPTION>
------------
   EXTENDED
    PRICE
------------
<S>             <C>
    [***]
     ---

---------------
    [***]
     ---

---------------
    [***]
     ---

---------------
    [***]
     ---

---------------
    [***]
     ---

---------------
    [***]
     ---

---------------
    [***]
     ---

---------------
    [***]
     ---

---------------
    [***]
---------------
</TABLE>

*** Confidential treatment has been requested for certain redacted provisions of
this agreement. The redacted provisions are identified by three asterisks
enclosed by brackets and underlined. The confidential portion has been filed
separately with the Securities and Exchange Commission.

                                      B-2
<PAGE>   10

SHIPMENT SCHEDULE FOR Q2/2000:

<TABLE>
<CAPTION>
------------------------------------------------------------------------------------------------------------------------------------
  LINE      QTY         MODEL NO.                          DESCRIPTION                     LIST        DISCOUNT       DISCOUNT
  ITEM                                                                                     PRICE         RATE           PRICE
------------------------------------------------------------------------------------------------------------------------------------
<S>        <C>      <C>                 <C>                                              <C>           <C>           <C>
    1      [***]   AN-3220              AN-3200 20-slot 23" Chassis. - 48 VDC power.     $ 7,995         [***]        [***]
            ---                                                                              ---          ---          ---
------------------------------------------------------------------------------------------------------------------------------------
    2      [***]   SYSMOD1-DS3-2        System Combo Card includes system processor,     $ 7,085         [***]        [***]
            ---                         1-port Ethernet 10/100TX, 1 console port.  2         ---          ---          ---
                                        PREINSTALLED DS-3 (45MBPS) ATM WAN UPLINK
                                        DAUGHTERCARDS.
------------------------------------------------------------------------------------------------------------------------------------
    3      [***]   LC12-T1              12-channel line card supports ATM over           $ 8,995         [***]        [***]
            ---                         unchannelized T1.12 integral T1 modems with          ---          ---          ---
                                        CSU/DSU on daughtercards.
------------------------------------------------------------------------------------------------------------------------------------
    4      [***]   VSIC-8TC             8-channel T1 and Voice Server Card with          $18,995         [***]        [***]
            ---                         hardware support for voice compression.              ---          ---          ---
                                        8 DS-1 channelized T1 digital voice
                                        interfaces for connection to PBX or
                                        Class 5 switches. Supports 192 channels
                                        of G.711 PCM or 96 voice channels of
                                        voice compression. Supports G.168 echo
                                        cancellation and structured CES service
                                        via CBR voice over AAL1 and rtVBR voice
                                        over AAL2. Hardware ready for G.726.
                                        Software for compression is sold
                                        separately. REQUIRED MULTI-SERVICE
                                        GATEWAY SYSTEM SOFTWARE.
------------------------------------------------------------------------------------------------------------------------------------
    5      [***]   MSAP-SW-GW3.0        Multi-Service Gateway System software            $ 4,995         [***]        [***]
            ---                         version 3.0                                         ---           ---          ---
                                        Required with any purchase of voice
                                        module with MSAP unit.
------------------------------------------------------------------------------------------------------------------------------------
    6      [***]   MSAP-SW-VCMP3.0      G.726 Voice compression software for 96          $ 2,995         [***]        [***]
            ---                         voice channels Voice Server Card.                    ---          ---          ---
                                        THIS OPTION MUST BE PURCHASED FOR EACH
                                        VOICE SERVER CARD THAT NEEDS VOICE
                                        COMPRESSION.
------------------------------------------------------------------------------------------------------------------------------------
</TABLE>

<TABLE>
<CAPTION>
------------
EXTENDED
 PRICE
------------
<S>             <C>
[***]
 ---
------------
[***]
 ---

------------
[***]
 ---

------------
[***]
 ---

------------
[***]
 ---

------------
[***]
 ---

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

*** Confidential treatment has been requested for certain redacted provisions of
this agreement. The redacted provisions are identified by three asterisks
enclosed by brackets and underlined. The confidential portion has been filed
separately with the Securities and Exchange Commission.

                                      B-3
<PAGE>   11

<TABLE>
<CAPTION>
------------------------------------------------------------------------------------------------------------------------------------
  LINE      QTY         MODEL NO.                          DESCRIPTION                     LIST        DISCOUNT     DISCOUNT
  ITEM                                                                                     PRICE         RATE         PRICE
------------------------------------------------------------------------------------------------------------------------------------
<S>        <C>      <C>                 <C>                                              <C>           <C>           <C>
    7      [***]   AP v2.4              Access Pilot EMS S/W support 50 fully loaded     $9,995          [***]        [***]
            ---                         MSAPs                                               ---           ---          ---
------------------------------------------------------------------------------------------------------------------------------------
    8      [***]   AN-30T               Integrated Access Device Base Unit.  1-port      $2,395          [***]        [***]
            ---                         Ethernet 10/100TX, 2-ports Serial V.35/V.11         ---           ---          ---
                                        (Slimline 26 connectors), 1-port ATM WAN
                                        over unchannelized T1 up to 1.544 Mbps
                                        with built-in CSU/DSU, and 1-slot for
                                        factory installed Voice Interface
                                        Module. Includes manual, Ethernet cable,
                                        and SDSL cable. REQUIRES SLIMLINE 26
                                        CONNECTOR TO V.35 SERIAL CABLE
                                        (CDXEXXX-XX), PLEASE REFER TO THE
                                        CABLING SECTION OF THE PRICE LIST FOR
                                        ORDERING OPTIONS. REQUIRES A
                                        CONFIGURATION WORKSHEET WITH EVERY
                                        ORDER.
------------------------------------------------------------------------------------------------------------------------------------
    9      [***]   AN-30VM-D24C         Digital Voice Module for AN-30.  24-DS0          $3,600          [***]        [***]
            ---                         digital voice channels with 2-ports T1              ---           ---          ---
                                        for drop & insert functionality.
                                        Hardware supports G.711 PCM and G.168
                                        echo cancellation. Hardware ready for
                                        voice compression requirements. Software
                                        for compression is sold separately.
------------------------------------------------------------------------------------------------------------------------------------
   11      [***]   AN-30-SW-DCMP3.0     G.726 ADPCM voice compression software for       $  695          [***]        [***]
            ---                         24-ports digital voice module.                      ---           ---          ---
------------------------------------------------------------------------------------------------------------------------------------
   12      [***]   AN-30-SW-DSS2.2      Dynamic Service Selection Software for the       $  300          [***]        [***]
            ---                         AN-30 IAD.                                          ---           ---          ---
------------------------------------------------------------------------------------------------------------------------------------
   13      [***]   AN-30-SW-B3.0        Basic System Software version 2.2 for the             0          [***]        [***]
            ---                         AN-30 IAD. W/routing                                ---           ---          ---
------------------------------------------------------------------------------------------------------------------------------------
   14      [***]   AN-20T               Integrated Access Device Base Unit.              $  895          [***]        [***]
            ---                         Includes 1-port Ethernet 10BT and 1-port ATM        ---           ---          ---
                                        WAN over unchannelized T1 (integral
                                        CSU/DSU).
------------------------------------------------------------------------------------------------------------------------------------
</TABLE>

<TABLE>
<CAPTION>
------------
EXTENDED
  PRICE
------------
<S>             <C>
[***]
 ---

------------
[***]
 ---

------------
[***]
 ---

------------
[***]
 ---

------------
[***]
 ---

------------
[***]
 ---

------------
[***]
 ---

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

*** Confidential treatment has been requested for certain redacted provisions of
this agreement. The redacted provisions are identified by three asterisks
enclosed by brackets and underlined. The confidential portion has been filed
separately with the Securities and Exchange Commission.

                                      B-4
<PAGE>   12

<TABLE>
<CAPTION>
------------------------------------------------------------------------------------------------------------------------------------
  LINE      QTY         MODEL NO.                          DESCRIPTION                     LIST        DISCOUNT       DISCOUNT
  ITEM                                                                                     PRICE         RATE           PRICE
------------------------------------------------------------------------------------------------------------------------------------
<S>        <C>      <C>                 <C>                                              <C>           <C>           <C>
   15      [***]   AN-20-SW-B2.2        Basic System Software version 2.2 for the             0          [***]        [***]
            ---                         AN-20 IAD. W/routing.                               ---           ---          ---
------------------------------------------------------------------------------------------------------------------------------------
   16      [***]   AN-20-SW-DSS2.2      Dynamic Service Selection Software version         $200          [***]        [***]
            ---                         2.2 for the AN-20 IAD.                              ---           ---          ---
------------------------------------------------------------------------------------------------------------------------------------
                                                                                       TOTAL PRICE:
------------------------------------------------------------------------------------------------------------------------------------
</TABLE>

<TABLE>
<CAPTION>
------------
   EXTENDED
    PRICE
------------
<S>             <C>
[***]
 ---

------------
[***]
 ---

------------
[***]
------------
</TABLE>

*** Confidential treatment has been requested for certain redacted provisions of
this agreement. The redacted provisions are identified by three asterisks
enclosed by brackets and underlined. The confidential portion has been filed
separately with the Securities and Exchange Commission.

                                      B-5
<PAGE>   13

SHIPMENT SCHEDULE FOR Q3/2000:

<TABLE>
<CAPTION>
------------------------------------------------------------------------------------------------------------------------------------
  LINE      QTY         MODEL NO.                          DESCRIPTION                     LIST        DISCOUNT       DISCOUNT
  ITEM                                                                                     PRICE         RATE           PRICE
------------------------------------------------------------------------------------------------------------------------------------
<S>        <C>      <C>                 <C>                                              <C>           <C>           <C>
    1      [***]   AN-3220              AN-3200 20-slot 23" Chassis. - 48 VDC power.     $ 7,995         [***]        [***]
            ---                                                                             ---           ---          ---
------------------------------------------------------------------------------------------------------------------------------------
    2      [***]   SYSMOD1-DS3-2        System Combo Card includes system processor,     $ 7,085         [***]        [***]
            ---                         1-port Ethernet 10/100TX, 1 console port.  2        ---           ---          ---
                                        PREINSTALLED DS-3 (45MBPS) ATM WAN UPLINK
                                        DAUGHTERCARDS.
------------------------------------------------------------------------------------------------------------------------------------
    3      [***]   LC12-T1              12-channel line card supports ATM over           $ 8,995         [***]        [***]
            ---                         unchannelized T1.12 integral T1 modems with         ---           ---          ---
                                        CSU/DSU on daughtercards.
------------------------------------------------------------------------------------------------------------------------------------
    4      [***]   VSIC-8TC             8-channel T1 and Voice Server Card with          $18,995         [***]        [***]
            ---                         hardware support for voice compression.             ---           ---          ---
                                        8 DS-1 channelized T1 digital voice
                                        interfaces for connection to PBX or
                                        Class 5 switches. Supports 192 channels
                                        of G.711 PCM or 96 voice channels of
                                        voice compression. Supports G.168 echo
                                        cancellation and structured CES service
                                        via CBR voice over AAL1 and rtVBR voice
                                        over AAL2. Hardware ready for G.726.
                                        Software for compression is sold
                                        separately. REQUIRED MULTI-SERVICE
                                        GATEWAY SYSTEM SOFTWARE.
------------------------------------------------------------------------------------------------------------------------------------
    5      [***]   MSAP-SW-GW3.0        Multi-Service Gateway System software            $ 4,995         [***]        [***]
            ---                         version 3.0                                         ---           ---          ---
                                        Required with any purchase of voice
                                        module with MSAP unit.
------------------------------------------------------------------------------------------------------------------------------------
    6      [***]   MSAP-SW-VCMP3.0      G.726 Voice compression software for 96          $ 2,995         [***]        [***]
            ---                         voice channels Voice Server Card.                   ---           ---          ---
                                        THIS OPTION MUST BE PURCHASED FOR EACH
                                        VOICE SERVER CARD THAT NEEDS VOICE
                                        COMPRESSION.
------------------------------------------------------------------------------------------------------------------------------------
</TABLE>

<TABLE>
<CAPTION>
------------
   EXTENDED
    PRICE
------------
<S>             <C>
  [***]
   ---
------------
 [***]
  ---

------------
  [***]
   ---

------------
  [***]
   ---

------------
  [***]
   ---

------------
  [***]
   ---

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

*** Confidential treatment has been requested for certain redacted provisions of
this agreement. The redacted provisions are identified by three asterisks
enclosed by brackets and underlined. The confidential portion has been filed
separately with the Securities and Exchange Commission.

                                      B-6
<PAGE>   14

<TABLE>
<CAPTION>
------------------------------------------------------------------------------------------------------------------------------------
  LINE      QTY         MODEL NO.                          DESCRIPTION                     LIST        DISCOUNT       DISCOUNT
  ITEM                                                                                     PRICE         RATE           PRICE
------------------------------------------------------------------------------------------------------------------------------------
<S>        <C>      <C>                 <C>                                              <C>           <C>           <C>
    7      [***]   AP v2.4              Access Pilot EMS S/W support 50 fully loaded     $ 9,995         [***]        [***]
            ---                         MSAPs                                               ---           ---          ---
------------------------------------------------------------------------------------------------------------------------------------
    8      [***]   AN-30T               Integrated Access Device Base Unit.  1-port      $ 2,395         [***]        [***]
            ---                         Ethernet 10/100TX, 2-ports Serial V.35/V.11         ---           ---          ---
                                        (Slimline 26 connectors), 1-port ATM WAN
                                        over unchannelized T1 up to 1.544 Mbps
                                        with built-in CSU/DSU, and 1-slot for
                                        factory installed Voice Interface
                                        Module. Includes manual, Ethernet cable,
                                        and SDSL cable. REQUIRES SLIMLINE 26
                                        CONNECTOR TO V.35 SERIAL CABLE
                                        (CDXEXXX-XX), PLEASE REFER TO THE
                                        CABLING SECTION OF THE PRICE LIST FOR
                                        ORDERING OPTIONS. REQUIRES A
                                        CONFIGURATION WORKSHEET WITH EVERY
                                        ORDER.
------------------------------------------------------------------------------------------------------------------------------------
    9      [***]   AN-30VM-D24C         Digital Voice Module for AN-30.  24-DS0          $ 3,600         [***]        [***]
            ---                         digital voice channels with 2-ports T1              ---           ---          ---
                                        for drop & insert functionality.
                                        Hardware supports G.711 PCM and G.168
                                        echo cancellation. Hardware ready for
                                        voice compression requirements. Software
                                        for compression is sold separately.
------------------------------------------------------------------------------------------------------------------------------------
   11      [***]   AN-30-SW-DCMP3.0     G.726 ADPCM voice compression software for       $   695         [***]        [***]
            ---                         24-ports digital voice module.                       ---          ---          ---
------------------------------------------------------------------------------------------------------------------------------------
   12      [***]   AN-30-SW-DSS2.2      Dynamic Service Selection Software for the       $   300         [***]        [***]
            ---                         AN-30 IAD.                                           ---          ---          ---
------------------------------------------------------------------------------------------------------------------------------------
   13      [***]   AN-30-SW-B3.0        Basic System Software version 2.2 for the              0         [***]        [***]
            ---                         AN-30 IAD. W/routing                                 ---          ---          ---
------------------------------------------------------------------------------------------------------------------------------------
   14      [***]   AN-20T               Integrated Access Device Base Unit.              $   895         [***]        [***]
            ---                         Includes 1-port Ethernet 10BT and 1-port ATM         ---          ---          ---
                                        WAN over unchannelized T1 (integral
                                        CSU/DSU).
------------------------------------------------------------------------------------------------------------------------------------
</TABLE>

<TABLE>
<CAPTION>
------------
   EXTENDED
    PRICE
------------
<S>             <C>
  [***]
   ---

------------
  [***]
   ---

------------
  [***]
   ---

------------
  [***]
   ---

------------
  [***]
   ---

------------
  [***]
   ---

------------
  [***]
   ---

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

*** Confidential treatment has been requested for certain redacted provisions of
this agreement. The redacted provisions are identified by three asterisks
enclosed by brackets and underlined. The confidential portion has been filed
separately with the Securities and Exchange Commission.

                                      B-7
<PAGE>   15

<TABLE>
<CAPTION>
------------------------------------------------------------------------------------------------------------------------------------
  LINE      QTY         MODEL NO.                          DESCRIPTION                     LIST        DISCOUNT       DISCOUNT
  ITEM                                                                                     PRICE         RATE           PRICE
------------------------------------------------------------------------------------------------------------------------------------
<S>        <C>      <C>                 <C>                                              <C>           <C>           <C>
   15      [***]   AN-20-SW-B2.2        Basic System Software version 2.2 for the             0          [***]        [***]
            ---                         AN-20 IAD. W/routing.                               ---           ---          ---
------------------------------------------------------------------------------------------------------------------------------------
   16      [***]   AN-20-SW-DSS2.2      Dynamic Service Selection Software version         $200          [***]        [***]
            ---                         2.2 for the AN-20 IAD.                              ---           ---          ---
------------------------------------------------------------------------------------------------------------------------------------
                                                                                       TOTAL PRICE:
------------------------------------------------------------------------------------------------------------------------------------
</TABLE>

<TABLE>
<CAPTION>
------------
   EXTENDED
    PRICE
------------
<S>             <C>
  [***]
   ---

------------
  [***]
   ---

------------
  [***]
------------
</TABLE>

*** Confidential treatment has been requested for certain redacted provisions of
this agreement. The redacted provisions are identified by three asterisks
enclosed by brackets and underlined. The confidential portion has been filed
separately with the Securities and Exchange Commission.

                                      B-8
<PAGE>   16

SHIPMENT SCHEDULE FOR Q4/2000:

<TABLE>
<CAPTION>
------------------------------------------------------------------------------------------------------------------------------------
  LINE      QTY         MODEL NO.                          DESCRIPTION                     LIST        DISCOUNT       DISCOUNT
  ITEM                                                                                     PRICE         RATE           PRICE
------------------------------------------------------------------------------------------------------------------------------------
<S>        <C>      <C>                 <C>                                              <C>           <C>           <C>
    1      [***]   AN-3220              AN-3200 20-slot 23" Chassis. -48 VDC power.      $ 7,995         [***]        [***]
            ---                                                                             ---           ---          ---
------------------------------------------------------------------------------------------------------------------------------------
    2      [***]   SYSMOD1-DS3-2        System Combo Card includes system processor,     $ 7,085         [***]        [***]
            ---                         1-port Ethernet 10/100TX, 1 console port.  2        ---           ---          ---
                                        PREINSTALLED DS-3 (45MBPS) ATM WAN UPLINK
                                        DAUGHTERCARDS.
------------------------------------------------------------------------------------------------------------------------------------
    3      [***]   LC12-T1              12-channel line card supports ATM over           $ 8,995         [***]        [***]
            ---                         unchannelized T1.12 integral T1 modems with         ---           ---          ---
                                        CSU/DSU on daughtercards.
------------------------------------------------------------------------------------------------------------------------------------
    4      [***]   VSIC-8TC             8-channel T1 and Voice Server Card with          $18,995         [***]        [***]
            ---                         hardware support for voice compression.             ---           ---          ---
                                        8 DS-1 channelized T1 digital voice
                                        interfaces for connection to PBX or
                                        Class 5 switches. Supports 192 channels
                                        of G.711 PCM or 96 voice channels of
                                        voice compression. Supports G.168 echo
                                        cancellation and structured CES service
                                        via CBR voice over AAL1 and rtVBR voice
                                        over AAL2. Hardware ready for G.726.
                                        Software for compression is sold
                                        separately. REQUIRED MULTI-SERVICE
                                        GATEWAY SYSTEM SOFTWARE.
------------------------------------------------------------------------------------------------------------------------------------
    5      [***]   MSAP-SW-GW3.0        Multi-Service Gateway System software            $ 4,995         [***]        [***]
            ---                         version 3.0                                         ---           ---          ---
                                        Required with any purchase of voice
                                        module with MSAP unit.
------------------------------------------------------------------------------------------------------------------------------------
    6      [***]   MSAP-SW-VCMP3.0      G.726 Voice compression software for 96          $ 2,995         [***]        [***]
            ---                         voice channels Voice Server Card.                   ---           ---          ---
                                        THIS OPTION MUST BE PURCHASED FOR EACH
                                        VOICE SERVER CARD THAT NEEDS VOICE
                                        COMPRESSION.
------------------------------------------------------------------------------------------------------------------------------------
</TABLE>

<TABLE>
<CAPTION>
------------
   EXTENDED
    PRICE
------------
<S>             <C>
[***]
 ---
------------
[***]
 ---

------------
[***]
 ---

------------
[***]
 ---

------------
[***]
 ---

------------
[***]
 ---

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

*** Confidential treatment has been requested for certain redacted provisions of
this agreement. The redacted provisions are identified by three asterisks
enclosed by brackets and underlined. The confidential portion has been filed
separately with the Securities and Exchange Commission.

                                      B-9
<PAGE>   17

<TABLE>
<CAPTION>
------------------------------------------------------------------------------------------------------------------------------------
  LINE      QTY         MODEL NO.                          DESCRIPTION                     LIST        DISCOUNT       DISCOUNT
  ITEM                                                                                     PRICE         RATE           PRICE
------------------------------------------------------------------------------------------------------------------------------------
<S>        <C>      <C>                 <C>                                              <C>           <C>           <C>
    7      [***]   AP v2.4              Access Pilot EMS S/W support 50 fully loaded     $9,995          [***]        [***]
            ---                         MSAPs                                               ---           ---          ---
------------------------------------------------------------------------------------------------------------------------------------
    8      [***]   AN-30T               Integrated Access Device Base Unit.  1-port      $2,395          [***]        [***]
            ---                         Ethernet 10/100TX, 2-ports Serial V.35/V.11         ---           ---          ---
                                        (Slimline 26 connectors), 1-port ATM WAN
                                        over unchannelized T1 up to 1.544 Mbps with
                                        built-in CSU/DSU, and 1-slot for factory
                                        installed Voice SDSL cable. REQUIRES
                                        SLIMLINE 26 CONNECTOR TO V.35 SERIAL
                                        CABLE (CDXEXXX-XX), PLEASE REFER TO THE
                                        CABLING SECTION OF THE PRICE LIST FOR
                                        ORDERING OPTIONS. REQUIRES A
                                        CONFIGURATION WORKSHEET WITH EVERY
                                        ORDER.
------------------------------------------------------------------------------------------------------------------------------------
    9      [***]   AN-30VM-D24C         Digital Voice Module for AN-30.  24-DS0          $3,600          [***]        [***]
            ---                         digital voice channels with 2-ports T1              ---           ---          ---
                                        for drop & insert functionality.
                                        Hardware supports G.711 PCM and G.168
                                        echo cancellation. Hardware ready for
                                        voice compression requirements. Software
                                        for compression is sold separately.
------------------------------------------------------------------------------------------------------------------------------------
   11      [***]   AN-30-SW-DCMP3.0     G.726 ADPCM voice compression software for       $  695          [***]        [***]
            ---                         24-ports digital voice module.                      ---           ---          ---
------------------------------------------------------------------------------------------------------------------------------------
   12      [***]   AN-30-SW-DSS2.2      Dynamic Service Selection Software for the       $  300          [***]        [***]
            ---                         AN-30 IAD.                                          ---           ---          ---
------------------------------------------------------------------------------------------------------------------------------------
   13      [***]   AN-30-SW-B3.0        Basic System Software version 2.2 for the             0          [***]        [***]
            ---                         AN-30 IAD. W/routing                                ---           ---          ---
------------------------------------------------------------------------------------------------------------------------------------
   14      [***]   AN-20T               Integrated Access Device Base Unit.              $  895          [***]        [***]
            ---                         Includes 1-port Ethernet 10BT and 1-port ATM        ---           ---          ---
                                        WAN over unchannelized T1 (integral
                                        CSU/DSU).
------------------------------------------------------------------------------------------------------------------------------------
</TABLE>

<TABLE>
<CAPTION>
------------
   EXTENDED
    PRICE
------------
<S>             <C>
[***]
 ---

------------
[***]
 ---

------------
[***]
 ---

------------
[***]
 ---

------------
[***]
 ---

------------
[***]
 ---

------------
[***]
 ---

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

*** Confidential treatment has been requested for certain redacted provisions of
this agreement. The redacted provisions are identified by three asterisks
enclosed by brackets and underlined. The confidential portion has been filed
separately with the Securities and Exchange Commission.

                                      B-10
<PAGE>   18

<TABLE>
<CAPTION>
------------------------------------------------------------------------------------------------------------------------------------
  LINE      QTY         MODEL NO.                          DESCRIPTION                     LIST        DISCOUNT       DISCOUNT
  ITEM                                                                                     PRICE         RATE           PRICE
------------------------------------------------------------------------------------------------------------------------------------
<S>        <C>      <C>                 <C>                                              <C>           <C>           <C>
   15      [***]   AN-20-SW-B2.2        Basic System Software version 2.2 for the             0          [***]        [***]
            ---                         AN-20 IAD. W/routing.                               ---           ---          ---
------------------------------------------------------------------------------------------------------------------------------------
   16      [***]   AN-20-SW-DSS2.2      Dynamic Service Selection Software version         $200          [***]        [***]
            ---                         2.2 for the AN-20 IAD.                              ---           ---          ---
------------------------------------------------------------------------------------------------------------------------------------
                                                                                       TOTAL PRICE:
------------------------------------------------------------------------------------------------------------------------------------
                                                                                       GRAND TOTAL:
------------------------------------------------------------------------------------------------------------------------------------
</TABLE>

<TABLE>
<CAPTION>
------------
   EXTENDED
    PRICE
------------
<S>             <C>
[***]
 ---

------------
[***]
 ---

------------
[***]
------------
[***]
------------
</TABLE>

*** Confidential treatment has been requested for certain redacted provisions of
this agreement. The redacted provisions are identified by three asterisks
enclosed by brackets and underlined. The confidential portion has been filed
separately with the Securities and Exchange Commission.

                                      B-11
<PAGE>   19

                                  ATTACHMENT C
                     RESIDENT ENGINEER AND TRAINING PROGRAM

        Accelerated Networks will provide at [***] during the first 12 months
        of UniDial's deployment a Resident Engineer starting [***] after the
        effective date of this agreement. Description and cost savings are
        described below. [***]

        Accelerated Networks will provide [***] to UniDial a total of [***]
        training seats with a class load of [***] persons maximum, which equates
        to [***] classes of on site training. UniDial may allocate a portion of
        the [***] seats as desired to Accelerated Network's HQ Training
        facility following appropriate scheduling timelines. Descriptions and
        cost savings to UniDial are described below. [***]

<TABLE>
<CAPTION>
----------------------------------------------------------------------------------------------------
<S>                                             <C>                    <C>
ACCELERATEDSTART SERVICE DESCRIPTION                 RESOURCES                   PRICING
PROFESSIONAL SERVICES
----------------------------------------------------------------------------------------------------
ON-SITE NETWORK OPERATIONS SUPPORT              ANI will deliver      3 Mos. [***]
                                                                              ---
Accelerated Networks can provide Resident       this service          6 Mos. [***]
                                                                              ---
Engineering personnel to serve as onsite                              12 Mos. [***]
                                                                               ---
support resource(s) at the customer's Network
Operation Center (NOC). The Resident
Engineer(s) have the responsibility to monitor
the ANI portion of the customer network to
ensure all faults are addressed as soon as one
may arise. In addition to the monitoring and
fault management of the Accelerated Networks
based network, the engineer(s) will assist in
managing the day to day process of integrating
and implementing major additions/transitions
to the Accelerated Networks-based network.
----------------------------------------------------------------------------------------------------
TRAINING                                        Will be offered       At Accelerated Networks
Accelerated Networks Educational Services       primarily by ANI      Training facilities in
offers focused hands-on courses to train        resources.  Third     Moorpark, CA
customer staff on the installation,             party training        PER STUDENT - [***]
                                                                                     ---
operations, troubleshooting and management of   facilities and        Includes course material,
the Accelerated Networks based networks.        trainers will be      instructor, facilities and
Classes are offered in Simi Valley, CA, or at   investigated.  Web    equipment.
the customer's premise.  Accelerated Networks   based and CD based    At Customer's Site
may supply all necessary equipment for          (CBT) programs are    PER STUDENT - [***]
                                                                                     ---
classes at the customer's site.  Maximum of 8   scheduled.            Includes course material,
students per class.  Technical Training                               instructor and expenses.
courses include topics such as:                                       Customer provides facilities
                                                                      and equipment.
    -   AccessPilot and CoPilot Element                               Accelerated Networks crates
        Management System (EMS)                                       and ships all necessary

    -   Configuration and Operations for                              Equipment to Customer's
        AN-20/24/28/30/31/32 and 3220/3204                            Site.  Maximum of 8 students
        multiservice access platform                                  per class.

    -   Installation and Maintenance for the                          EQUIPMENT - [$8995.]
        ANI devices                                                   Includes all needed equipment
                                                                      inclusive of Routers, Switches and
    -   Troubleshooting Accelerated Networks                          PBX simulators.
        Frame Relay, ATM, SDSL, and Voice
----------------------------------------------------------------------------------------------------
</TABLE>

*** Confidential treatment has been requested for certain redacted provisions of
this agreement. The redacted provisions are identified by three asterisks
enclosed by brackets and underlined. The confidential portion has been filed
separately with the Securities and Exchange Commission.

                                      C-1
<PAGE>   20

<TABLE>
<CAPTION>
----------------------------------------------------------------------------------------------------
<S>                                             <C>                    <C>
ACCELERATEDSTART SERVICE DESCRIPTION                 RESOURCES                   PRICING
PROFESSIONAL SERVICES
----------------------------------------------------------------------------------------------------
Networks
----------------------------------------------------------------------------------------------------
LAB SERVICES                                    This lab is an        No charge for validation of
The AcceleratedStart customer lab is            internal resource.    an ANI solution.
available to customers and account teams to     Third party
test and evaluate their solutions.  The lab     interoperability
has a variety of routers, Frame Relay and ATM   testing is being
switches, third party DSLAMs, CPE and test      evaluated.
equipment available to test specific
applications.
----------------------------------------------------------------------------------------------------
</TABLE>

                                      C-2
<PAGE>   21

                                   ATTACHMENT D
                            TECHNICAL SUPPORT PROGRAMS

        ACCELERATED NETWORKS WILL HONOR A [***] DISCOUNT OFF LIST FOR A 1 YEAR
        CONTRACT PAID IN ADVANCE

        ACCELERATED NETWORKS WILL HONOR A [***] DISCOUNT OFF LIST FOR A 2 YEAR
        CONTRACT PAID IN ADVANCE

        ACCELERATED NETWORKS WILL HONOR A [***] DISCOUNT OFF LIST FOR A 3 YEAR
        CONTRACT PAID IN ADVANCE

<TABLE>
<CAPTION>
---------------------------------------------------------------------------------------------------
             ACCELERATEDTAC SERVICES                      RESOURCES                PRICING
---------------------------------------------------------------------------------------------------
<S>                                                 <C>                      <C>
ACCELERATEDTAC PROGRAMS                             ANI Network Support     See pricing on next
Accelerated Networks Support Programs are           Engineers will assist   page
packaged to meet your network hardware and          24 hours a day 7 days
software needs.  Our Web Support, Remote            a week.  On site
Technical Support, On-Site Remedial Maintenance     trained and certified
and Repair and Replace services are expertly        authorized
prepared to ensure that Accelerated Networks        representatives
customer's network health is maintained at its      provide support.
optimum.

ACCELERATEDTAC BASIC                                PARTNER LIST
_x9 (local customer time) Telephone TAC support     UNISYS
with 45 minutes response.  Includes minor
software releases (bug fix) and WebTAC Access.

ACCELERATEDTAC ENHANCED
Basic service, 7x24 Telephone TAC support with
15 minutes response.  Includes minor software
releases (bug fix) and WebTAC Access and next
business day advanced hardware replacement.

ACCELERATEDTAC PREMIUM
Enhanced service, 7x24 TAC access with 15 minutes
response.  Includes minor software releases (bug
fix) and WebTAC Access and next business day
on-site response.

ACCELERATEDTAC COMPREHENSIVE
Premium service, 7x24 TAC access with 15 minutes
response.  Includes minor software releases (bug
fix) and WebTAC Access, 4-hour on-site response
365 days a year.  Response time subject to
location.
---------------------------------------------------------------------------------------------------
</TABLE>

*** Confidential treatment has been requested for certain redacted provisions of
this agreement. The redacted provisions are identified by three asterisks
enclosed by brackets and underlined. The confidential portion has been filed
separately with the Securities and Exchange Commission.

                                      D-1
<PAGE>   22

                            TECHNICAL SUPPORT PRICING

<TABLE>
<CAPTION>
----------------------------------------------------
<S>                                     <C>
        CUSTOMER SERVICE                PRICE
----------------------------------------------------
ACCELERATEDTAC BASIC
----------------------------------------------------
AN-20                                    [***]
----------------------------------------------------
AN-24                                    [***]
----------------------------------------------------
AN-28                                    [***]
----------------------------------------------------
AN-30                                    [***]
----------------------------------------------------
AN-31                                    [***]
----------------------------------------------------
AN-32                                    [***]
----------------------------------------------------
AN-3204                                  [***]
----------------------------------------------------
AN-3220                                  [***]
----------------------------------------------------
ACCELERATEDTAC ENHANCED
----------------------------------------------------
AN-20                                    [***]
----------------------------------------------------
AN-24                                    [***]
----------------------------------------------------
AN-28                                    [***]
----------------------------------------------------
AN-30                                    [***]
----------------------------------------------------
AN-31                                    [***]
----------------------------------------------------
AN-32                                    [***]
----------------------------------------------------
AN-3204                                  [***]
----------------------------------------------------
AN-3220                                  [***]
----------------------------------------------------
ACCELERATEDTAC PREMIUM
----------------------------------------------------
AN-20                                    [***]
----------------------------------------------------
AN-24                                    [***]
----------------------------------------------------
AN-28                                    [***]
----------------------------------------------------
AN-30                                    [***]
----------------------------------------------------
AN-31                                    [***]
----------------------------------------------------
AN-32                                    [***]
----------------------------------------------------
AN-3204                                  [***]
----------------------------------------------------
AN-3220                                  [***]
----------------------------------------------------
</TABLE>

*** Confidential treatment has been requested for certain redacted provisions of
this agreement. The redacted provisions are identified by three asterisks
enclosed by brackets and underlined. The confidential portion has been filed
separately with the Securities and Exchange Commission.

                                      D-2
<PAGE>   23

<TABLE>
<CAPTION>
----------------------------------------------------
<S>                                     <C>
        CUSTOMER SERVICE                PRICE
----------------------------------------------------
ACCELERATEDTAC
COMPREHENSIVE 4 HOUR
----------------------------------------------------
AN-20                                    [***]
----------------------------------------------------
AN-24                                    [***]
----------------------------------------------------
AN-28                                    [***]
----------------------------------------------------
AN-30                                    [***]
----------------------------------------------------
AN-31                                    [***]
----------------------------------------------------
AN-32                                    [***]
----------------------------------------------------
AN-3204                                  [***]
----------------------------------------------------
AN-3220                                  [***]
----------------------------------------------------
ACCELERATEDTAC COMPREHENSIVE 2 HOUR
(CALL KEN OR ANSEL)
----------------------------------------------------
AN-20                                    [***]
----------------------------------------------------
AN-24                                    [***]
----------------------------------------------------
AN-28                                    [***]
----------------------------------------------------
AN-30                                    [***]
----------------------------------------------------
AN-31                                    [***]
----------------------------------------------------
AN-32                                    [***]
----------------------------------------------------
AN-3204                                  [***]
----------------------------------------------------
AN-3220                                  [***]
----------------------------------------------------
</TABLE>

*** Confidential treatment has been requested for certain redacted provisions of
this agreement. The redacted provisions are identified by three asterisks
enclosed by brackets and underlined. The confidential portion has been filed
separately with the Securities and Exchange Commission.

                                      D-3

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