<PAGE>   1
                                                                   EXHIBIT 10.14



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.







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







                      MATERIALS AND MANUFACTURING AGREEMENT



                                 BY AND BETWEEN

                             ARROW ELECTRONICS, INC.

                                       AND

                           ACCELERATED NETWORKS, INC.

                                      DATED

                                 MARCH 15, 1999







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


<PAGE>   2

                MATERIALS AND MANUFACTURING MANAGEMENT AGREEMENT
                             BOARD ASSEMBLY (ACTIVE)


               This Agreement is entered into as of 15 MARCH, 1999, by and
between ACCELERATED NETWORKS, INC. ("Customer") with its principal place of
business at 301 Science Drive, Moorpark, CA 93021 and the SEMICONDUCTOR GROUP of
Arrow Electronics, Inc. ("Arrow") with its principal place of business at 25 Hub
Drive, Melville, New York 11747-3509.

        The Customer and Arrow hereby agree as follows:

        1. WORK, ENGINEERING CHANGE ORDERS, ATTRITION KITS, MANUFACTURING YIELD,
           PAYMENT, PRICE, TAXES AND SUBCONTRACTORS

        1.1 WORK. Arrow agrees to use reasonable commercial efforts to perform
the work ("Work") pursuant to purchase orders or changes to purchase orders
issued by Customer and accepted by Arrow. Work shall mean to procure components
and other supplies ("Components") and to engage a subassembly house (the
"Subcontractor") to manufacture or assemble products ("Products") pursuant to
detailed, written specifications ("Specifications") for each such Product which
are provided by Customer and accepted by Arrow and to deliver such Products to a
Customer designated location. For each Product or revision thereof,
Specifications shall include but not be limited to bill of materials,
schematics, assembly drawings, test specifications, current revision number, and
a Customer approved Subcontractor and vendor list. All printed circuit boards
(PCBs) to be provided hereunder are listed in APPENDIX 1 hereto, and will amend
from time to time as mutually agreed upon.

        1.2 ENGINEERING CHANGE ORDERS. Any engineering change order or other
change that results in any revision to the Specifications for any Product
("ECO") must be in writing, signed and dated by Customer. Arrow will make a
reasonable best effort to acknowledge receipt of, and impact of and to sign and
return a copy of the revised Specifications to Customer within forty-eight (48)
hours of receipt by Arrow of such written notice. In the event that the price,
or delivery schedule, or both, are affected by the ECO(s), Arrow shall make a
reasonable best effort to notify Customer within forty-eight (48) hours as to
the impact of any such changes and shall provide Customer with the date when any
such ECO will become effective. Components that are affected by any ECO shall be
treated in accordance with Section 4.3 hereof. Arrow shall not take action on
any ECO from Customer until Customer has indicated in writing to Arrow that such
request is acceptable to Customer.

        1.3 INTENTIONALLY OMITTED (NOT APPLICABLE).

        1.4 MANUFACTURING YIELD. As part of the manufacturing process there will
be completed Products that the test procedures and equipment or
manufacturability will not "yield" as good. After review of the test procedures,
the supplied test equipment, and manufacturability by the Subcontractor, this
"yield" loss is not expected to exceed [***] of the total Products produced. The
Subcontractor will use available troubleshooting techniques and equipment, but
after due diligence the defective Products within this percentage will be
shipped

--------------------
*** 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>   3

separately from the "good" Products, marked as "Assembly Rejects" and invoiced
to the Customer at the contracted pricing. Product loss due to manufacturing or
handling errors or losses greater than the above percentage will be the
responsibility of the Subcontractor. After Customer's receipt and review of
these Assembly Rejects, if the defect was due to material defects or
manufacturing process errors the Customer's account will be credited for the
invoiced Product price.

        1.5 PAYMENT. Terms of payment shall be [***] from the date of invoice,
payable in U.S. Dollars.

        1.6 PRICE. Price for the Work shall be as agreed upon by Arrow and
Customer from time to time as set forth in purchase orders issued by Customer
and accepted by Arrow. Preliminary prices shall be as set forth in Appendix 1,
attached hereto, and made a part hereof. Arrow agrees to review pricing as set
forth in Appendix 1, with Customer, every ninety (90) days during the term of
this Agreement. Price reductions or increases (if applicable) shall be
negotiated on a case by case basis. In the event the parties are unable to
mutually agree on any such price change(s), within a thirty (30) day period from
notification thereof, unless otherwise mutually agreed, any such item(s) shall
be removed from Appendix 1, within the terms of this Agreement.

        1.7 TAXES. Customer shall be responsible for payment of all taxes
relating to the sale of the Products including but not limited to any license
fees and sales taxes.

        1.8 SUBCONTRACTORS. The Work may be performed, in whole or in part, by
third parties selected by Arrow and approved by Customer.

        2. COMPONENTS, WARRANTY AND RETURNS

        2.1 COMPONENTS. All Components, other materials and equipment required
in connection with the Work acquired or supplied by Arrow will be in compliance
with the Specifications, except Components, other materials or equipment which
are supplied by Customer ("Customer Components"). Arrow shall bear the risk of
loss for Customer Components while in Arrow's care and custody, while
Subcontractor shall bear the risk of loss for Customer Components while in its
care and custody.

        2.2 WARRANTY. Seller warrants to Buyer that Products purchased hereunder
will conform to the applicable manufacturer's specifications for such Products
and that any value-added work performed by Seller of such Products will conform
to the applicable Buyer's specifications relating to such work. Seller makes no
other warranty, express or implied, with respect to the Products. IN PARTICULAR,
SELLER MAKES NO WARRANTY RESPECTING THE MERCHANTABILITY OF THE PRODUCTS OR THEIR
SUITABILITY OR FITNESS FOR ANY PARTICULAR PURPOSE OR USE OR RESPECTING

--------------------
*** 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>   4

INFRINGEMENT. However, Seller will transfer to Buyer whatever transferable
warranties and indemnities Seller receives from the manufacturer of the
Products. With respect to Products which do not meet applicable manufacturer's
specifications and with respect to value-added work by Seller which does not
meet applicable Buyer's specifications, Seller's liability is limited (at
Seller's election) to (1) refund of Buyer's purchase price paid for such
Products (without interest), (2) repair of such Products, or (3) replacement of
such Products; provided, however, that such Products must be returned to Seller,
if Seller is unable to repair or replace despite diligent efforts, Seller shall
refund Buyer's purchase price paid for such Products (without interest) along
with acceptable evidence of purchase, within twenty (20) days from date of
delivery, transportation charges prepaid. NEITHER PARTY SHALL IN ANY EVENT BE
ENTITLED TO, AND NEITHER PARTY SHALL BE LIABLE FOR INDIRECT, SPECIAL, INCIDENTAL
OR CONSEQUENTIAL DAMAGES OF ANY NATURE INCLUDING, WITHOUT BEING LIMITED TO, LOSS
OF PROFIT, PROMOTIONAL OR MANUFACTURING EXPENSE, OVERHEAD, INJURY TO REPUTATION
OR LOSS OF CUSTOMERS. A PARTIES' RECOVERY FROM THE OTHER FOR ANY CLAIM SHALL NOT
EXCEED THE PURCHASE PRICE FOR THE PRODUCTS IRRESPECTIVE OF THE NATURE OF THE
CLAIM, WHETHER IN CONTRACT, TORT, WARRANTY, OR OTHERWISE. THE FOREGOING
LIMITATIONS SHALL NOT APPLY TO EITHER PARTIES INDEMNITY OBLIGATIONS OR BREACH OF
CONFIDENTIALITY UNDER SECTION 8 HEREUNDER.

        The attached A-Plus Manufacturing warranty statement (APPENDIX 4) is
incorporated by reference, and made a part hereof.

        2.3 RETURNS. Customer may return to Arrow any Product that does not
comply with the above warranty, provided that: (i) Customer obtains a return
material authorization ("RMA") from Arrow prior to returning the Product; (ii)
the Product is returned within applicable warranty period; and (iii) the product
deficiency is identified and attached to the Product. Any Product so returned to
Arrow shall be promptly repaired or replaced, or the purchase price therefor
refunded or credited price paid, at Arrow's option. Product determined to be
defect free after inspection will be returned to Customer and Customer will be
responsible for any inspection charges from Subcontractor. This shall be
Customer's sole and exclusive remedy for any breach of any warranty provided in
this Agreement. Seller agrees to make a reasonable best effort to replace
non-conforming material within ten (10) business days of return, freight
prepaid.

        3. LICENSE

        3.1 GRANT. Customer grants to Arrow, with the right to sublicense to the
Subcontractor or any replacement therefor, a license under any copyright,
patent, trade secret or other proprietary right necessary or useful for the
manufacture or assembly of the Products, solely for the purpose of performing
the Work pursuant to purchase orders issued by the Customer.

        3.2 OWNERSHIP. Customer represents and warrants that: (i) it owns the
entire right, title and interest to the Customer Components; (ii) the
performance of the Work does not infringe the proprietary rights of any third
party; and (iii) the Customer has the right and power to



                                       3
<PAGE>   5

enter into this Agreement. Customer agrees to indemnify Arrow and hold Arrow
harmless from and against any and all claims, losses, liabilities, damages,
expenses and costs (including attorneys' fees and court costs) that result from
a breach or alleged breach of any of these representations and warranties or
other obligations contained in this Agreement, or incurred in the settlement or
avoidance of any such claim.

        4. PURCHASE ORDER COMMITMENTS, SCHEDULE AND QUANTITY CHANGES,
           CANCELLATION, MINIMUM ORDER QUANTITY AND SAFETY STOCK

        4.1 PURCHASE ORDER COMMITMENTS. Customer will issue a purchase order
once per calendar month which specifies all Work to be completed within a
minimum of a 60 day period commencing on the date of the purchase order.
Included with each purchase order shall be a 90 day non-binding forecast
covering the period of beyond the aforementioned 60 day firm requirement. Each
purchase order shall reference the applicable Specifications.

        4.2 SCHEDULE AND QUANTITY CHANGES. Any change by Customer in the
quantity of Products or delivery date as contained in a purchase order shall be
subject to the prior written approval of Arrow except, however, Customer may
reschedule delivery of Products to a date no later than [***] beyond the
originally scheduled delivery date. Any change by Customer in the scheduled
delivery date to a date in excess of [***] from the originally scheduled
delivery date shall be deemed to be a cancellation unless otherwise agreed to by
Arrow in writing. Customer may not change the quantity of Products or delivery
date of Products within [***] of the scheduled delivery date. Customer shall be
liable for any additional costs or expenses incurred by Arrow as a result of any
change in the quantity of Products or delivery date by Customer.

        4.3 CANCELLATION. Except with respect to Components of Products which
have been previously identified to Customer as long lead time Components ("Long
Lead Time Components") listed in APPENDIX 2 or custom Components ("Custom
Components") listed in APPENDIX 3, Customer may cancel delivery of Products with
written notice at least 60 days prior to the scheduled delivery date without
cost or penalty. If Customer cancels delivery of Products less than 60 days
prior to the scheduled delivery date, or if the affected Components are Long
Lead Time Components or Custom Components, Arrow shall make reasonable
commercial efforts to: (i) return the affected Components to their manufacturer
(the "Supplier") or otherwise utilize any such Components; or (ii) cancel
Arrow's orders for such Components. Customer is not obligated to pay Arrow for
Components that are returned or Components on order which are canceled at no
cost to Arrow. In the event Arrow cannot return Components to their Supplier,
otherwise utilize or cancel future orders, Arrow will ship completed Products
and affected Components to Customer and Customer shall pay: (i) for all Products
that are in Arrow's or Subcontractor's possession as of the cancellation date
that have been produced for the canceled order; and (ii) Customer's resale price
of all of the affected Components. Customer authorizes

--------------------
*** 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.



                                       4
<PAGE>   6

Arrow to bill these charges within sixty (60) days of the effective date of
Customer's cancellation. Should Customer fail to place an order for any Product
for any continuous period of 60 days, the Components of such Product shall be
considered canceled and shall be treated in accordance with this Section 4.3.
Further, in the event that Arrow shall have actually purchased any Customer
Components from Customer, and any such Customer Components shall not have been
repurchased by Customer hereunder within sixty (60) days of their purchase by
Arrow, such Customer Components shall be considered canceled and Customer
authorizes Arrow to bill Customer Arrow's purchase price plus a management fee
of [***] for same.

        4.4 MINIMUM ORDER QUANTITY. Upon termination of this Agreement,
completion of any purchase order, or cessation of Customer's demand for any
Component, Customer shall pay Customer's resale price for all Excess Components.
Excess Components shall mean those Components specified by Customer which: (i)
are in Arrow's or Subcontractor's possession on the referenced date of
termination, completion or cessation of demand; (ii) were procured by Arrow as a
result of minimum order quantities for such Components established by their
Supplier; and (iii) cannot be returned to their Supplier or otherwise utilized
to fulfill any other Customer purchase order. Once each month Arrow shall
provide Customer with a listing of all such goods.

        4.5 SAFETY STOCK. Arrow shall maintain a stock ("Safety Stock") of
Products in an amount which is mutually determined, in writing, by Arrow and
Customer. Such Safety Stock of Products will involve the assembly of Products
separate from those Products assembled for the purpose of fulfilling Customer's
purchase orders. Upon termination of the Agreement, or cessation of Customer's
demand for any Product, Arrow shall deliver, and Customer shall accept delivery
of and pay for, such Safety Stock.

        5. SHIPPING

               Products will be shipped F.O.B. Subcontractor's facility, which
shall constitute delivery hereunder, with title and risk of loss or damage to
pass to Customer upon shipment. No single shipment shall exceed [***] in total
unless Customer has been notified Manager of Purchasing at least three (3)
business days prior to shipment. Products are deemed accepted by Customer unless
Customer notifies, Arrow within fifteen (15) days of delivery of Product
shortage, damage, or non-conformance.

        6. TERM AND TERMINATION

        6.1 TERM. This Agreement shall begin upon the date hereof and shall
continue in force for a initial twelve (12) month period, unless otherwise
terminated as provided for hereunder. This Agreement may be extended for
additional twelve (12) month terms by the mutual written consent of the parties
hereto

--------------------
*** 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.



                                       5
<PAGE>   7

        6.2 TERMINATION. This Agreement may be terminated by either party, in
whole or in part, with or without cause, upon sixty (60) days prior written
notice to the other party. The provisions of Section 4.3 hereof shall apply as
of the effective date of any termination. Termination of this Agreement shall
not affect the obligations of either party that exist as of the date of
termination.

        6.3 TERMINATION FOR DEFAULT. This agreement may be terminated
immediately for cause by either party in the event the other party; (i) shall
become insolvent; (ii) ceases to function as a going concern, or; (iii) fails to
perform any of its material obligations hereunder so as to be in default and
fails within thirty (30) days cure after prior written notice thereof.

        7. LIABILITY LIMITATION

        NOTWITHSTANDING ANYTHING ELSE IN THIS AGREEMENT, NEITHER PARTY WILL BE
LIABLE UNDER ANY SECTION OF THIS AGREEMENT OR UNDER ANY CONTRACT, NEGLIGENCE,
STRICT LIABILITY OR OTHER LEGAL OR EQUITABLE THEORY FOR INCIDENTAL, SPECIAL,
CONSEQUENTIAL OR PUNITIVE DAMAGES, LOST PROFITS, LOST BUSINESS, OR COST OF
PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES.

        8. CONFIDENTIALITY

        It is understood and agreed that the terms of this Agreement are
confidential, and no news release, advertisement or public announcement, or
denial or confirmation of the same, concerning any part of the subject matter of
this Agreement shall be made by either party hereto without the prior written
consent of the other party in each instance. Further, the parties hereto
acknowledge that, during the term hereof, they may become aware of confidential,
secret or proprietary information pertaining to the other party and its
operations (including, without limitation, information with respect to bidding,
pricing, suppliers and customers, or lists thereof, research, development and
engineering, and internal operations, inventory control, data processing,
technical data, and other procedures and systems) and that disclosure of such
information would materially and adversely affect the affected party. Each party
hereto agrees to maintain such confidentiality and secrecy and not to disclose
any such information to any person, firm or other entity, or to utilize the same
in any manner or form, except as may be expressly required by the terms and
conditions of this Agreement, or is required to be disclosed by judicial or
legal proceeding. Notwithstanding anything to the contrary, the confidentiality
provisions set forth in this Section 8 shall survive any termination of this
Agreement. Information extracted from a secured and encrypted area on either
parties Internet/Intranet web site, shall be considered confidential information
under the terms of this Agreement.

        9. MISCELLANEOUS

        9.1 GOVERNING LAW, DISPUTE RESOLUTION. This Agreement shall in all
respects be governed by and construed in accordance with the laws of the State
of California, excluding that body of laws known as conflict of laws. The
prevailing party in any legal action



                                       6
<PAGE>   8

or proceeding to enforce this Agreement shall be entitled to recover from the
non-prevailing party its reasonable attorneys' fees, and related costs and
disbursements, incurred in connection with such proceeding or the enforcement of
this Agreement. Both parties agree to waive trial by jury.

        9.2 FORCE MAJEURE. Nonperformance under this Agreement will be excused,
and neither party will bear any resulting liability to the other, to the extent
that such performance is rendered commercially impracticable or delayed by an
act of God or any other cause beyond the reasonable control of the nonperforming
party. The time for performance shall be extended for the time period lost by
reason of the delay, provided such delay shall not exceed sixty (60) days, or
this Agreement has been terminated as provided for in sub-section 6.3 hereunder.

        9.3 RELATIONSHIP OF PARTIES. The parties are and shall be independent
contractors to one another, and nothing herein shall be deemed to cause this
Agreement to create an agency, partnership, joint venture or any other
relationship between the parties.

        9.4 ASSIGNABILITY. Customer may not assign, delegate or otherwise
transfer any of its rights or obligations under this Agreement without Arrow's
prior written approval, which shall not be unreasonably withheld.

        9.5 NOTICES. Notices or other communications under this Agreement shall
be in writing and shall be effective when delivered personally or by overnight
courier, or mailed, postage prepaid, by certified or registered mail to each
party at the address set forth below (or to such other address as either party
may from time to time provide the other):

        Arrow Electronics, Inc.             Accelerated Networks, Inc.
        Semiconductor Group                 301 Science Drive
        25 Hub Drive                        Moorpark, CA 93021
        Melville, NY 11747
                                            Attention:  Manager of Purchasing
        Attention: Contracts Group                      Chief Financial Officer

        9.6 ENTIRE AGREEMENT; AMENDMENT; SEVERABILITY; AND WAIVER. This
Agreement represents the entire agreement between the parties concerning the
subject matter hereof, and may not be modified except in a writing signed by
both parties. This Agreement supersedes all proposals or quotations, oral or
written, and all negotiations, conversations, or discussions between or among
the parties relating to the subject matter of this Agreement. When interpreting
this Agreement precedence shall be given to the respective parts in the
following descending order: (i) this Agreement; (ii) any exhibits to this
Agreement; and (iii) if purchase orders are used to release Product, those
portions of the purchase order that are not pre-printed. Any waiver of any
provision of this Agreement must be in writing and signed by the party alleged
to have waived such provision, and any single waiver shall not operate to waive
subsequent or other defaults. The unenforceability of any provision of this
Agreement shall not affect the remaining provisions or any portions thereof.



                                       7
<PAGE>   9

               IN WITNESS WHEREOF, the parties hereto have caused this Agreement
to be executed by their duly authorized representatives as of the day and year
first above written.



ACCELERATED NETWORKS, INC.                ARROW ELECTRONICS, INC.
                                          ON BEHALF OF ITS SEMICONDUCTOR GROUP:

By:      /s/ Frederic T. Boyer             By:     /s/ A. Streber
    ---------------------------------          --------------------------------

Name:    Frederic T. Boyer                 Name:   A. Streber
      -------------------------------            ------------------------------

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

Date:   March 25, 1999                     Date:   April 1, 1999
      -------------------------------            ------------------------------



                                       8
<PAGE>   10

                                   APPENDIX I

                TO ACCELERATED NETWORKS, INC./ARROW/SEMICONDUCTOR

                MATERIALS AND MANUFACTURING MANAGEMENT AGREEMENT
                 BOARD ASSEMBLY (ACTIVE) DATED MARCH 15TH, 1999


                                       UNIT PRICE      MINIMUM RELEASE
    PCB#              DESCRIPTION         (USS)             QUANTITY
------------          -----------       ----------      ---------------



460-0003-001           COMBO CARD         [***]              [***]


--------------------
*** 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.


<PAGE>   11

                                   APPENDIX 2

                TO ACCELERATED NETWORKS, INC./ARROW/SEMICONDUCTOR

                MATERIALS AND MANUFACTURING MANAGEMENT AGREEMENT
                  BOARD ASSEMBLY (ACTIVE) DATED MARCH 15TH 1999


                            LONG LEAD TIME COMPONENTS



<TABLE>
<CAPTION>
ACCELERATED P/N           MFG             MFG P/N                    LEADTIME
---------------           ---             -------                    --------
<S>                       <C>             <C>                        <C>
001-00070-0641            SEEQ            LQ80224                    [***]

000-00002-0241            Dallas          DS1687-3                   [***]

000-00003-0321            MSYSTEMS        MD2200DO8 (WAS 8PB)        [***]

100-00020-1052            AVX             1206YG105ZA                [***]

101-00805-1046            AVX             08055G104MA                [***]

101-00805-1052            AVX             0805YG105MA                [***]
</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.

<PAGE>   12

                                   APPENDIX 3

                TO ACCELERATED NETWORKS, INC./ARROW/SEMICONDUCTOR

                MATERIALS AND MANUFACTURING MANAGEMENT AGREEMENT
                  BOARD ASSEMBLY (ACTIVE) DATED MARCH 15TH 1999

CUSTOM COMPONENTS


<TABLE>
<CAPTION>
ACCELERATED P/N          MFG              MFG P/N                  LEADTIME      NC/NR - Y/N
---------------          ---              -------                  --------      -----------
<S>                      <C>              <C>                      <C>           <C>
001-00068-3884           Lucent           LUC4ABO1388              [***]              Y

083-00001-001            Vicor            VI-JNO-EX-F3             [***]              Y

141-00010-0140           AMP              5-179010-6               [***]              Y

161-00001-0032           AMP              822273-1                 [***]              Y

060-00002-16665          Abracon          ACHL-16.667mhz           [***]              Y

023-002-0065             IDEA             G1831B/3EG               [***]              Y

062-0002-0025            Epliptek         EC11OOHSTS-25.OOOMG      [***]              Y

023-00001-0023           IERC             603-14/Q3                [***]              Y

140-00045-0008           AMP              406549-4                 [***]              Y

023-00001-0023           Lumex            5ML-LX120GG              [***]              Y

101-00603-1041           Kemet            C0603C104M8              [***]              Y

121-01206-0R12           Dale             WSL1206-.12              [***]              Y

140-00016-0002           Samtec           DW-02-16-L-S-300         [***]              Y
</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.

<PAGE>   13

                                   APPENDIX 4

                TO ACCELERATED NETWORKS, INC./ARROW/SEMICONDUCTOR

                MATERIALS AND MANUFACTURING MANAGEMENT AGREEMENT
                  BOARD ASSEMBLY (ACTIVE) DATED MARCH 15TH 1999

                        MANUFACTURING SERVICES AGREEMENT

                        WARRANTY FOR ACCELERATED NETWORKS


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


This Agreement effective as of this 18th day of March, 1999, by and between
A-Plus Manufacturing Corporation with offices at 2381 Bering Drive, Milpitas, CA
95131 ("Subcontractor") and Arrow Electronics, Inc., North American Component
Operations, with offices at 25 Hub Drive, Melville, NY 11747 ("Contractor").

"A-Plus Manufacturing Corporation warrants to Contractor and/or its Customer
that all products/services provided by it: (a) shall be of good quality and
workmanship and free from workmanship defects, (b) shall conform to all
specifications, drawings, description furnished, specified or adopted by Buyer
for a period of fifteen (15) months from the date of shipment."

IN WITNESS WHEREOF, the parties have duly executed this Agreement effective as
of the date set forth above.

Arrow Electronics, Inc.               A-Plus Manufacturing Corporation
     (Contractor)                             (Subcontractor)

By:     /s/ A. Streber                By:     /s/ Bill Yee
    --------------------------            --------------------------------------

Name:   A. Streber                    Name:   Bill Yee
      ------------------------              ------------------------------------
(Typed or Printed)                    (Typed or Printed)

Title:  President                     Title:  Senior V.P. of Operation
       -----------------------               -----------------------------------

Date:   4/1/99                        Date:   March 18, 1999
      ------------------------              ------------------------------------



<PAGE>   14


ACCELERATED NETWORKS, INC.
       (Customer)

By:     /s/ Frederic T. Boyer

Name:   Frederic T. Boyer
      -----------------------------------
(Typed or Printed)

Title:  Chief Financial Officer
       ----------------------------------
Date:   March 25, 1999
      -----------------------------------






<PAGE>   15
April 12, 2000




Frederic T. Boyer
Chief Financial Officer
Accelerated Networks, Inc.
301 Science Drive
Moorpark, CA 93021

Subject: LETTER AMENDMENT NO. 1 TO REFERENCED AGREEMENT


Re:      Semiconductor Group & Accelerated Networks Materials and Manufacturing
         Agreement Board Assembly (Active), dated March 15, 1999

Dear Mr. Boyer:

When signed by both parties, this Amendment shall modify the above referenced
agreement as follows:

As provided for in Section 6.1 of the referenced Agreement the parties hereby
extend the referenced Agreement, effective March 15, 2000, an additional twelve
(12) months.

All remaining terms and conditions of the above referenced Agreement shall
remain the same.

As an indication of your acceptance of this Amendment, please sign in the space
below, returning one (1) original (or FAX Copy to 516-391-1259) for our file.

<TABLE>
<S>                                                   <C>
Sincerely,                                            AGREED:  ACCELERATED NETWORKS, INC.

ARROW ELECTRONICS, INC.
On behalf of its Semiconductor Group

                                                      By:    /s/ Frederic T. Boyer
                                                           ------------------------------
Glenn T. Moore                                        Date:  4/21/00
Manager, Contracts & Proposals
Arrow Electronics, Inc.

Cc:  Marty Townsend - (GV) 818-878-4352
</TABLE>