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                                                                 EXHIBIT 10.17.2

                                AMENDMENT NO. 02

                                     to the

               Agreement for Purchase of Products - OEM Agreement

      Dated 21 January 1999 Between Accelerated Networks, Inc. (hereinafter
        "ANI"), and Siemens Carrier Networks LLC (hereinafter "Siemens")
      successor in interest to certain business of Siemens Information and
                  Communication Networks, Inc. ("Agreement").

WHEREAS, Siemens has entered into an agreement with WinStar Communications, Inc.
further amended to incorporated Accelerated Products ("WinStar Agreement"); and

WHEREAS, Siemens requested Accelerated Networks modify the terms and conditions
of the Agreement to incorporate certain changes and considerations
("Amendment"), and

WHEREAS, Siemens further requested Accelerated Networks to modify the terms and
conditions of the Agreement to incorporate other changes and considerations with
the purpose to cover certain provisions of the WinStar Agreement ("Amendment
2"), and

WHEREAS, such changes shall be applicable only to the extent that Siemens is
dealing with WinStar and its affiliates as its end user customer under the above
referenced Winstar Agreement. In all other cases, unless specifically modified
or changed in a separate amendment, the Agreement shall remain in full force and
effect.

NOW, THEREFORE, in consideration of the premises and the covenants hereinafter
contained, the parties hereto agree to amend the Agreement as follows:


1. SCOPE OF THIS AMENDMENT:

   This amendment complements and modifies the Agreement and its attachments,
   amendments, exhibits and schedules to incorporate certain changes with the
   intent of supporting certain terms and conditions of the Winstar Agreement.

2. DEFINITIONS:

   Wherever the word Siemens is set forth in the Agreement and in this Amendment
   it shall mean Siemens Carrier Networks LLP.


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3. THE FOLLOWING PROVISIONS ARE INCORPORATED HEREBY TO THE AGREEMENT:

   3.1 CHANGE PROCEDURES

       (a)  During the Warranty Period and Extend Warranty Period, Siemens shall
            be entitled to all Software updates, enhancements, releases, patches
            and error corrections developed by ANI. ANI shall give due
            consideration and implement all reasonable modifications,
            enhancements and patches to the Software as prioritized by the user
            group and within the agreed upon timeframes.

       (b)  ANI shall also develop and provide for sale to Siemens System
            modifications and enhancements and new commercially available
            products in accordance with the following:

            (i)   From time to time during the term of the Agreement, Siemens
                  may provide to ANI a proposed change in or addition to the
                  System or a written idea for a new product. Siemens and ANI
                  shall schedule a meeting to discuss the proposal as soon as
                  practicable following ANI receipt of the proposal. All such
                  proposals shall be considered Siemens Confidential Information
                  and Siemens proprietary information for purposes hereof;
                  provided, however, that this will not restrict the parties
                  making the item subject of the proposal an agreed upon
                  commercial product as provided in this Subsection (b).

            (ii)  Following the meeting, ANI shall propose a unit price for
                  equipment (i.e., the price for Siemens to purchase following
                  development of the item) or a one time fee with respect to
                  software items, and delivery schedule applicable to Siemens'
                  proposal. In determining such price, if the proposed changes
                  or additions include a request for ANI to correspondingly
                  reduce or eliminate any components of the Systems it is then
                  providing, such components shall be considered "Replacements."
                  In that event, the Parties shall determine the costs and
                  expenses required to provide the Replacements and the
                  reduction in the costs and expenses related to the components
                  being replaced, and there shall be an equitable adjustment in
                  the applicable price for such costs and expense being
                  replaced.

            (iii) If Siemens in its sole discretion accepts such unit price or
                  one time fee with respect to software items and delivery
                  schedule (A) ANI, at its sole cost and expense, shall design,
                  develop and manufacture (or program with respect to software
                  items) or have manufactured (or programmed with respect to
                  software items) such changes/additions or new products in
                  accordance with the proposed delivery schedule and (B) Siemens
                  shall grant ANI (including its suppliers, if necessary) all
                  rights it has as necessary to permit ANI (including its
                  suppliers, if necessary) to design, develop, manufacture and
                  exploit such changes/additions or new products as contemplated
                  under this Subsection (b) with no additional compensation
                  other than as stated in Subsection (iv) below.


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            (iv)  In consideration for Siemens providing the proposal for the
                  change in or addition to the System or the new product, ANI
                  shall provide an additional discount of ten (10%) for each
                  unit purchased by Siemens or with respect to the one time fee
                  for software and an additional ten percent (10%) discount on
                  all System components impacted by the change/addition or new
                  product for a period of six (6) months following commercial
                  availability of the change/addition or new product. All
                  changes/additions to the System and new products developed
                  under this Subsection (b) shall be warranted and supported by
                  ANI as if part of the System when first deployed.

       (c)  If ANI does not desire to implement/consider Siemens' proposal under
            Subsections (a) or (b) above or if the Parties are unable to agree
            upon the unit price, delivery schedule or any other term surrounding
            the proposed changes in Subsection (b) above and if Siemens has
            taken delivery of Systems and/or Services under this Agreement,
            Siemens may require ANI to provide changes in or additions to the
            System or new products pursuant to the following:

            (i)   The procedure in Subsections (b)(i) and (ii) above shall be
                  followed.

            (ii)  In addition, ANI shall promptly provide a detailed itemization
                  of its estimated direct and actual costs (i.e., no markup or
                  overhead expenses) to design and develop the change/addition
                  to the System or new product, as applicable (the "Development
                  Cost"). Siemens agrees to provide such estimate using its best
                  good faith. The Parties shall meet if requested by Siemens to
                  discuss and negotiate such Development Cost and establish a
                  reasonable payment schedule therefore; provided, that, no less
                  than thirty percent (30%) of the total Development Cost shall
                  be withheld until final acceptance of the change/addition or
                  new product by Siemens and Siemens shall be entitled to a full
                  refund of all amounts paid in the event the change/addition or
                  new product is not accepted by Siemens in accordance with a
                  mutually agreed upon acceptance test. The acceptance testing
                  and critical milestones for the development of the
                  change/addition or new product shall also be established by
                  the Parties and the Parties will each appoint a project leader
                  for such activities.


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            (iii) If Siemens in its sole discretion accepts such Development
                  Cost and the unit price and delivery schedule, ANI shall
                  design, develop and manufacture such changes/additions or new
                  products in accordance with the proposed delivery schedule for
                  the Development Cost. ANI shall retain financial records
                  related to the Development Cost and Siemens shall be entitled
                  to audit all such Development Cost.

            (iv)  In consideration for Siemens providing the proposal and
                  payment of the Development Cost for the change in or addition
                  to the System or the new product, ANI shall provide an
                  additional discount of ten (10%) for each such change/addition
                  or new product unit purchased by Siemens and an additional ten
                  percent (10%) discount on all System components impacted by
                  the change/addition or new product for a period of six (6)
                  months following commercial availability of the
                  change/addition or new product. In addition, Siemens shall
                  have an exclusive right to use such change/addition to the
                  System or new product, including all direct derivatives
                  thereof (i.e., ANI shall not sell or otherwise distribute or
                  provide, either directly or indirectly, the change/additions
                  to the System or new products to any other person or entity)
                  (the "Exclusive Right"). All changes/additions to the System
                  and new products developed under this Subsection (b) shall be
                  warranted and supported by Siemens as if part of the System
                  when purchased by Siemens.

            (v)   In the event ANI desires to sell or otherwise distribute any
                  change/addition to the System or new product that Siemens paid
                  the Development Cost and received the Exclusive Right, ANI
                  shall notify Siemens and Siemens shall grant ANI (including
                  its suppliers, if necessary) all rights it has as necessary to
                  permit ANI (including its suppliers, if necessary) to design,
                  develop, manufacture and exploit such changes/additions with
                  no additional compensation other than as stated in this
                  Subsection (v)) upon Siemens fulfilling one of the following
                  options as elected solely by Siemens: (1) a lump sum payment
                  by Siemens to Siemens of an amount equal to four times the
                  Development Cost or (2) a lump sum payment by ANI to Siemens
                  of an amount equal to three times the Development Cost
                  together with a six month exclusivity period for use of the
                  change/addition to the System or new product by Siemens or (3)
                  payment of a five percent (5%) royalty for all future sales of
                  the change/addition.


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       (d) Notwithstanding anything to the contrary herein, no changes in or
           additions to Systems or new products provided herein, or additional
           costs therefore, shall be made unless approved in writing by the
           Siemens' Contract Manager.

   3.2 SYSTEMS AND SERVICES WARRANTIES

       "Warranty Period" shall mean fifteen (15) months from the date of
       shipment. Siemens may extend the Warranty Period one or more times in its
       sole discretion, for additional consecutive one year periods each, upon
       payment of the Extended Warranty fee of fifteen (15%) percent of the
       invoiced price for all hardware provided to Siemens, for the WinStar
       Agreement, during the twelve (12) months prior to the extension date of
       the Extended Warranty Period, which shall be charged to Siemens only once
       a year but paid quarterly. The discounts provided in the System Price and
       Warranty Schedule attached shall apply ("Schedule A").

            (a) ANI warrants that Systems provided under this Agreement shall be
                free from defects in design, material and workmanship, and shall
                operate in accordance with the Specifications during the
                Warranty Period and any Extended Warranty Period.

            (b) ANI represents, warrants and covenants that all Equipment
                components (including spare parts) provided hereunder shall be
                new, not refurbished or re-manufactured, except that replacement
                Equipment and components may be refurbished or remanufactured.

            (c) ANI warrants that it shall maintain the Systems such that the
                Systems conform to the Specifications during the Warranty Period
                and Extended Warranty Period. Such maintenance shall include:

                (i)     in accordance with the procedures set forth in Schedule
                        Q of the WinStar Agreement, repairs on Equipment,
                        including any repairs recommended by third-party
                        manufacturers;

                (ii)    providing any modification or enhancements that are
                        necessary to maintain the Systems in compliance with
                        Applicable Standards (excluding, however, standards
                        established by Bellcore and IEEE unless such standards
                        are provided to other customers of ANI under warranty or
                        extended warranty), as well as Documentation related to
                        such enhancements;


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                (iii)   providing any release, update, alteration, modification,
                        enhancement or improvement that is generally available
                        to ANI's other customers under warranty or extended
                        warranty;

                (iv)    providing engineering changes and maintaining the
                        availability of Equipment parts and sub-parts,
                        consistent with the Equipment redundancy design;

                (v)     providing code corrections or maintenance patches
                        (including, all bug fixes, error correction, revisions,
                        modifications, and maintenance recommended by
                        third-party vendors) will be supplied to correct a
                        Defect in order to bring the Software into conformance
                        with applicable System Specifications. Siemens shall
                        also replace the Software if the media is destroyed or
                        damaged unless and to the extent the damage is on
                        account of Siemens or its customers improper use (which
                        shall not be improper use if used in accordance with the
                        documentation or as instructed by ANI's) and as a result
                        such Software are unusable or fail to operate in
                        accordance with the applicable System Specifications;

                (vi)    providing all improvements, enhancements, extensions,
                        upgrades and other changes to the Software. ANI shall
                        concurrently provide updated Documentation reflecting
                        such changes. ANI shall also supply, when necessary,
                        updated Software required to cause the Software to
                        operate with upgraded Equipment (including engineering
                        changes) or under new versions or releases of the
                        operating system or other system software designed for
                        the Software;

                (vii)   providing telephone support to Siemens in order to
                        assist Siemens or its customers to locate and correct
                        functional or operational problems with the System. Such
                        support shall be provided on a 24 hour, 7 days per week
                        basis via Siemens help desk. ANI's technical engineering
                        support is available 8:00 a.m. to 8:00 p.m. EST during
                        normal business days. In addition, ANI's technical
                        engineering support is available on a 24 hour, 7 days
                        per week basis for Critical Problems as designated by
                        Siemens. ANI shall provide a single contact number for
                        Siemens to report problems; and

                (viii)  in the event of Software problems that cannot be
                        corrected with telephone support or on a remote basis
                        within the applicable Performance Standards, ANI shall
                        provide on-site assistance free of charge. However, if
                        the problem is due to Siemens' acts or omissions and
                        on-site assistance is required, ANI's personnel rates
                        set forth in Schedule A will apply.


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            (d) ANI represents and warrants that it shall maintain the
                availability of Equipment parts and sub-parts, consistent with
                the Equipment redundancy design, for a period of five (5) years
                from manufacturing. Subject to the foregoing support periods,
                ANI shall provide to Siemens written notification at least one
                (1) year prior to the discontinuation of manufacture of any
                System components associated with this Agreement to permit
                Siemens a last time purchase opportunity; provided, however,
                during the term of the Agreement ANI shall only discontinue
                System components in the event there is a replacement component
                that will permit the Systems to continue to meet or exceed the
                Specifications. ANI acknowledges and agrees that it shall not
                utilize this "discontinuation" provision as a means to cease
                supplying Systems or components thereof during the term of the
                Agreement.

            (e) ANI warrants that it shall stock spare Equipment parts and
                provide 14 day availability of such parts; provided, however,
                Siemens shall provide 24 hour availability of spare Equipment
                parts that Siemens requires to resolve a Critical Problem.

            (f) ANI warrants that all upgrades to Equipment and Software shall
                be backward compatible to existing Systems and prior releases.
                In no event shall Siemens be required to upgrade its Software if
                such upgrade requires a corresponding Equipment upgrade. In such
                event, ANI shall continue to support the release of the Software
                that did not require a corresponding Equipment upgrade as set
                forth in this Agreement. Equipment upgrades to implement
                Software enhancements or improvements that Siemens desires to
                implement shall be provided to Siemens at mutually agreed upon
                unit rates.

            (g) ANI shall provide access to appropriate technical resources to
                Siemens' appropriate personnel in order to resolve any problem
                that Siemens cannot resolve through lower level support,
                including help desk support and field service support for errors
                that cannot be remotely diagnosed and cured.

            (h) In the event of a breach of the foregoing representations,
                warranties and covenants during the Warranty Period or an
                Extended Warranty Period, and upon written notice from Siemens
                describing the breach, ANI shall at no additional cost to
                Siemens: (i) in the case of Equipment, repair or replace such
                Equipment so that it is compliant with the warranty within the
                time period specified as part of the Performance Standards, and
                (ii) in the case of Services, immediately re-perform the
                Services.


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            (i) The foregoing representations and warranties will not apply if
                and to the extent, and so long as not caused by ANI or its
                subcontractors or agents where:

                (i)   defects in Equipment delivered hereunder are caused by
                      alteration, modification, or repair by any person other
                      than ANI's or its subcontractors or agents or due to an
                      act of God; provided, however, the foregoing exclusion
                      shall not apply with respect to Siemens or Siemens'
                      subcontractors' making of spare changes or if an
                      alteration, modification or repair is authorized by the
                      Documentation or otherwise by ANI or its subcontractors or
                      agents in writing;

                (ii)  defects are caused by Siemens or Siemens' suppliers or
                      subcontractors mishandling or abuse, excluding
                      specifically ANI, its Affiliates and their suppliers and
                      subcontractors; or

                (iii) defects are caused from improper operation,
                      interconnection or installation by any person other than
                      ANI or its subcontractors.

The terms and conditions of this Amendment 2 supercede any conflicting terms and
conditions of the Agreement and any amendments to in regard to the procurement
of Systems set forth in the Winstar Agreement. Unless otherwise stated herein,
the remaining terms and conditions of the Agreement are unchanged and remain in
full force and effect.

IN WITNESS WHEREOF, this Amendment has been executed and delivered by the
undersigned officers, thereunto, duly authorized, as of the date last written
below.

ACCELERATED NETWORKS, INC.                 SIEMENS CARRIER NETWORKS LLC

BY:    /s/ Ronald A. Hughes                BY:    /s/ John D. McGoun

NAME:  Ronald A. Hughes                    NAME:  John D. McGoun

TITLE: Director of Contracts               TITLE: Manager, Subcontracts

DATE:  12/01/00                            DATE:  12/01/00


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