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                                                                   EXHIBIT 10.35


                                                CONFIDENTIAL TREATMENT REQUESTED
                                            UNDER 17 C.F.R. (S)(S) 200.80(B)(4),
                                                            200.83 AND 240.24B-2


                         EQUIPMENT PURCHASE AGREEMENT

     This Equipment Purchase Agreement (the "Agreement") is entered into as of
July 21, 1999 (the "Effective Date"), by and between NorthPoint Communications,
Inc., a company duly organized and existing under the laws of the State of
Delaware ("Customer"), and Copper Mountain Networks, Inc., a company duly
organized and existing under the laws of the State of Delaware ("Copper
Mountain").

                                    Recital

     Whereas, Copper Mountain desires to sell to Customer, and Customer desires
to purchase from Copper Mountain, a Digital Subscriber Line ("DSL") networking
system.

     Now, Therefore, Copper Mountain and Customer hereby agree as follows:

                                   Agreement

1.   Definitions

     "Acceptance" means Customer's final and irrevocable acceptance of the
Equipment in accordance with the terms of this Agreement.

     "Blanket Purchase Order" means the two non-cancelable Purchase Orders
issued prior to each calendar quarter by Customer as outlined in Exhibit B
attached hereto.

     "Defective" means the Equipment fails to operate substantially in
accordance with the specifications set forth in the documentation provided to
Customer under normal use and service.

     "Equipment" means the Network Equipment and Subscriber Equipment being
purchased under this Agreement by Customer.

     "Firmware" has the meaning set forth in the Software License Agreement
between Copper Mountain and Customer entered into concurrently with the
execution of this Agreement.

     "Forecast" has the meaning set forth in Section 2.4.

     "Line Cards" means the portion of the Network Equipment comprised of the
printed circuit board assemblies, which contain the line or port capacity of the
Network Equipment.

     "Minimum Volume Commitment" means the minimum volume commitment of
Equipment to be purchased by and delivered to Customer each quarter as set forth
on Exhibit B.

     "Network Equipment" means the infrastructure DSL networking equipment
(i.e., a high-performance, carrier-class platform) and related materials that
will be used to implement the System (e.g., CE200s).

     "Product Milestone Specifications" means the product milestone
specifications to be incorporated by Copper Mountain into new Equipment as set
forth on Exhibit D.

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     "Purchase Order" means a written purchase order submitted to Copper
Mountain by Customer setting forth the number of units of Network Equipment and
Subscriber Equipment to be purchased and the requested shipping date.

     "Purchase Price" means the price of the Equipment to be paid by Customer to
Copper Mountain as set forth in Exhibit A, subject to the discount set forth on
Exhibit B.

     "Special or Non-Standard Parts" means any component of the Equipment, which
is not on Copper Mountain's bill of materials.

     "Subscriber Equipment" means the subscriber equipment that will be used to
connect subscribers within the System to the Network Equipment to provide high-
speed access to the Internet and other data services (e.g., CopperRockets).

     "System" means the Equipment and the System Software.

     "System Software" means the Firmware furnished and licensed to Customer
under the Software License Agreement between Copper Mountain and Customer to be
executed concurrently with this Agreement.

     "Term" has the meaning set forth in Section 12.1.

     "Warranty Period" means twelve (12) months after shipment of the Equipment
to Customer.

2.   Purchase of Equipment

     2.1  Purchase of Equipment. In accordance with and subject to the terms and
conditions of this Agreement, Customer hereby orders and agrees to purchase from
Copper Mountain, and Copper Mountain hereby accepts and agrees to sell to
Customer, the Equipment. The System Software shall be licensed, not sold, to
Customer under the terms of the Software License Agreement.

     2.2  Minimum Volume Commitment. Customer acknowledges and agrees that,
pursuant to the terms hereof, Copper Mountain has provided to Customer favorable
pricing for the Equipment in return for and in reliance upon Customer's promise
to purchase and take delivery of the Minimum Volume Commitment.

     2.3  Product Milestone Specifications. Customer acknowledges and agrees
that, pursuant to the terms hereof, Copper Mountain has provided to Customer a
commitment with respect to the commercial availability of new Equipment which
meets the Product Milestone Specifications in return for and in reliance upon
Customer's promise to purchase and take delivery of the Minimum Volume
Commitment.

     2.4  Forecasts. On or before the 15/th/ day of each month during the Term,
Customer shall submit a written forecast, or approve a forecast as prepared
mutually with Copper Mountain, to Copper Mountain, (the "Forecast") which shall
set forth the estimated number of

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units of Equipment to be purchased in each month during the twelve (12) month
period beginning with the month for which such Forecast is being delivered.

3.   Purchase Price and Payment

     3.1  Purchase Price. Customer shall pay to Copper Mountain the Purchase
Price for the Equipment as set forth on Exhibit A, less a discount as set forth
on Exhibit B. Both parties acknowledge that the Purchase Price shall not include
any maintenance or support above and beyond the warranty set forth in Section 7.

     3.2  Payment Schedule. Customer shall pay all invoices issued under this
Agreement within thirty (30) days from the date of invoice. Shipments,
deliveries and performance of work will at all times be subject to the approval
of Copper Mountain. In the event that the Customer has not met the payment
schedule set forth in this Section 3.2, Copper Mountain may at any time decline
to make any shipments or deliveries or perform any work except upon receipt of
payment or upon terms and conditions or security satisfactory to Copper
Mountain. In no event shall Copper Mountain decline to make any shipments or
deliveries or perform any work, unless Copper Mountain has notified Customer in
writing of any overdue amounts and Customer has not paid all overdue amounts to
Copper Mountain within ten (10) days from the date of such notice.

     3.3  Taxes. Customer shall pay any and all taxes (other than taxes based
upon Copper Mountain's net income), duties, assessments and other charges and
expenses of any nature whatsoever imposed by any government authority in
connection with the delivery of the Equipment to Customer or the payment of the
Purchase Price.

     3.4  Late Charges; Offsets. Copper Mountain reserves the right to charge
Customer a late payment fee on any past due amounts at the rate of one percent
(1%) per month or the maximum amount permitted by law, whichever is less.

4.   Orders and Delivery

     4.1  Procedure. Customer shall purchase Equipment from Copper Mountain by
submitting a Purchase Order to Copper Mountain.

     4.2  Acceptance of Purchase Orders. All Purchase Orders submitted by
Customer to Copper Mountain shall be subject to acceptance by Copper Mountain at
its offices in San Diego, California. Copper Mountain shall, within one (1)
business day of receipt of each Purchase Order, confirm receipt of such Purchase
Order with Customer by facsimile or electronic mail. Additionally, Copper
Mountain shall, within three (3) business days of receipt of each Purchase Order
provide the estimated date of shipment for each such Purchase Order to customer
by facsimile or electronic mail. Purchase Orders shall not be binding on Copper
Mountain until such written confirmation.

     4.3  Controlling Terms. All Equipment purchased by Customer from Copper
Mountain during the Term shall be subject to the terms and conditions of this
Agreement. Any terms or conditions appearing on the face or reverse side of any
Purchase Order,

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acknowledgment, or confirmation that are different from or in addition to those
required hereunder shall not be binding on the parties, even if signed and
returned, unless both parties hereto agree in a separate writing to be bound by
such different or additional terms and conditions.

     4.4  Cancellation or Postponement by Copper Mountain. Copper Mountain may
cancel or postpone any Purchase Order placed with, and accepted by, Copper
Mountain if Customer fails to make any payment when due as provided in Section
3.2 or is in default as set forth in Section 12.2.

     4.5  Cancellation by Customer. Customer shall be allowed to cancel any
Purchase Order placed with, and accepted by, Copper Mountain if the cancellation
is received at least thirty (30) days prior to the requested delivery date;
provided, however, that in the event of such cancellation Customer shall be
liable to Copper Mountain for payment of Copper Mountain's costs for any Special
or Non-Standard Parts purchased or which Copper Mountain is obligated to
purchase, such payment to be made to Copper Mountain within thirty (30) days
after the date of such cancellation.

     4.6  Postponement by Customer. Customer shall be allowed to postpone any
Purchase Order placed with, and accepted by, Copper Mountain if the postponement
is received at least fifteen (15) days prior to the requested delivery date;
provided, however, that in no event shall any such postponement delay shipment
of the Equipment for more than forty-five (45) days from the delivery date in
the original Purchase Order. Additionally, in the event of such postponement,
Customer shall be liable to Copper Mountain for payment of Copper Mountain's
costs for any Special or Non-Standard Parts purchased or which Copper Mountain
is obligated to purchase, such payment to be made to Copper Mountain within
thirty (30) days after the date of such postponement.

     4.7  Equipment Availability. Copper Mountain will use reasonable efforts to
fill all Purchase Orders within forty-five (45) days of the date such Purchase
Orders are accepted by Copper Mountain, subject to Equipment availability from
Copper Mountain and its manufacturing sub-contractors and Copper Mountain's
production and supply schedules. Should Purchase Orders for Equipment exceed
Customer's current Forecast, Copper Mountain will allocate its available
inventory and make deliveries on a basis Copper Mountain deems equitable, in its
sole discretion, and without liability to Customer on account of the method of
allocation chosen or its implementation. However, Copper Mountain shall not be
liable to Customer or any third party for any damages due to Copper Mountain's
failure to fill any Purchase Order or for any delay in delivery or error in
filling any Purchase Order for any reason whatsoever, except to the extent such
damages result from the gross negligence or willful misconduct of Copper
Mountain.

     4.8  Delivery. All Equipment delivered pursuant to the terms of this
Agreement shall be suitably packaged, marked for shipment and delivered by
common carrier of Customer's choice, FOB Copper Mountain's plant in San Diego,
California, or any other plant or warehouse designated by Copper Mountain.

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     4.9  Title; Risk of Loss; Shipping Costs. Title to (exclusive of the rights
retained under the Agreement in the Firmware, patents, copyrights, trade secrets
and intellectual property) and all risk of loss or damage for any Equipment
purchased hereunder shall pass to Customer upon delivery of such Equipment by
Copper Mountain to a common carrier for shipment to Customer. All freight,
handling, insurance, duties, taxes and shipping expense shall be borne by
Customer.

5.   Acceptance

     The Equipment shipped to Customer under any Purchase Order shall be deemed
accepted by Customer unless a written notice of defect is received by Copper
Mountain within fifteen (15) days following receipt of the Equipment by
Customer.  Under no circumstances shall acceptance or lack thereof affect the
warranties set forth in Section 7.

6.   Documentation

     On or before delivery of the Equipment to which such documentation applies,
Copper Mountain shall provide to Customer, at no additional charge, the
documentation for such Equipment.  Customer shall use and reproduce such
documentation solely for the purpose of operating and maintaining the System.

7.   Warranties

     7.1  Network Equipment Limited Warranty. During the applicable Warranty
Period for Network Equipment, Copper Mountain warrants to Customer that the
Network Equipment shall be free from material defects in workmanship and
materials under normal use and service and shall operate substantially in
accordance with the specifications set forth in the documentation provided to
Customer. This warranty does not apply to any item of Network Equipment that (a)
has been altered, modified, or improperly repaired; (b) has been the subject of
misuse, negligence, accident, or improper storage or installation; or (c) has
been used or maintained in any manner other than in accordance with
documentation provided by Copper Mountain.

     7.2  Warranty Claims for Network Equipment. Before submitting any warranty
claim to Copper Mountain, Customer shall perform first echelon diagnosis
(including identification and isolation of Network Equipment problems to the
board level and removal and replacement of hardware, firmware and software).
Copper Mountain shall provide Customer with reasonably requested aid in
performing such diagnosis. At Copper Mountain's request, Customer shall return
allegedly Defective Network Equipment to Copper Mountain at Customer's expense;
if such Network Equipment is determined by Copper Mountain to be Defective,
Copper Mountain shall reimburse Customer within thirty (30) days following
receipt of such Network Equipment for the expenses of shipping such Network
Equipment to Copper Mountain. If Copper Mountain does not request Customer to
return Defective Network Equipment to Copper Mountain, Copper Mountain shall
repair or replace such Network Equipment, in accordance with Section 7.3.

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     7.3  Exclusive Remedies for Network Equipment. If, during the applicable
Warranty Period, Customer reports in writing a claim that any Network Equipment
is Defective in breach of the warranty in Section 7.1, Copper Mountain shall, as
Customer's sole and exclusive remedy for breach of this limited warranty and at
Copper Mountain's option, either repair or replace the Defective Network
Equipment. Copper Mountain shall bear all travel, lodging and related out-of-
pocket expenses for required on-site repair and replacement of Defective Network
Equipment covered by the warranty in Section 7.1. In the event that advanced
replacement equipment or components are required to complete warranty repairs on
Defective equipment, such equipment or components shall be shipped to customer
prior to customer's return of such Defective equipment. Any Network Equipment
which is repaired by Copper Mountain pursuant to this Section 7.3 shall be
warranted for the remainder of the applicable Warranty Period as provided in
Section 7.1; provided, however, that any System subcomponents replaced by Copper
Mountain hereunder shall be warranted for twelve (12) months after shipment of
such System subcomponents to Customer.

     7.4  Limited Warranty for Subscriber Equipment. The sole and exclusive
warranty for Subscriber Equipment is set forth in Exhibit E.

     7.5  Disclaimer of Warranties.

          (a)  EXCEPT AS EXPRESSLY SET FORTH IN SECTION 7.1 AND EXHIBIT E,
COPPER MOUNTAIN MAKES NO WARRANTIES, EXPRESS OR IMPLIED, WITH RESPECT TO ANY
EQUIPMENT PROVIDED BY COPPER MOUNTAIN UNDER THIS AGREEMENT, INCLUDING, BUT NOT
LIMITED TO, ANY WARRANTY OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE.

          (b)  Customer acknowledges that it has not relied on any
representations or warranties regarding the Equipment other than those in
Section 7.1 and Exhibit E.

     7.6  End-User Warranties. Customer shall indemnify, defend and hold
harmless Copper Mountain for and against any end user warranty claim offered by
Customer that is outside the warranties of this Agreement, including, but not
limited to, valid consumer warranty claims arising outside the applicable
Warranty Period.

8.   Infringement Claims

     8.1  Indemnification. Subject to Sections 8.3 and 9, Copper Mountain shall
defend and indemnify at its own expense and shall hold Customer harmless from
any claim that Customer's authorized and proper use of any Equipment infringes a
U.S. patent or copyright of any third party, and shall pay any damages finally
awarded in an action against Customer that are specifically attributable to such
a claim and any amounts agreed to in settlement of such a claim, provided that
Customer (a) promptly notifies Copper Mountain in writing of the claim, (b)
gives Copper Mountain the sole authority to control the defense and settlement
of the claim, and (c) cooperates and, at Copper Mountain's request and expense,
assists in the defense of the claim.

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     8.2  Mitigation. If any infringement claim covered by Section 8.1 arises or
in Copper Mountain's opinion is likely to occur, Copper Mountain may, at its
option, (a) procure for Customer the right to use the infringing Equipment, (b)
replace the infringing Equipment with non-infringing substitute equipment of
equal grade and quality, or (c) refund to Customer the Purchase Price paid for
the infringing Equipment. If Customer continues to use Equipment after receiving
notice of a claim or a ruling that Customer's use of such Equipment infringes a
third party's rights, Customer shall be responsible for any liability resulting
from such continued use of the Equipment.

     8.3  Exclusions. Copper Mountain shall have no liability to Customer for
any claim described in Section 8.1 if the claim is based on or arises from
Customer's (a) improper or unauthorized use or modification of the Equipment, or
(b) combination or use of the Equipment with equipment, software, data or other
items not furnished by Copper Mountain (or authorized by Copper Mountain in
writing for such combination or use), if the claim would not have arisen but for
the combination. Customer shall indemnify and hold Copper Mountain harmless for
and against any and all liability, damages, losses, costs and expenses
(including attorney's fees) arising from any claim described in this Section
8.3.

     8.4  Entire Liability. Section 8 sets forth Customer's exclusive remedy and
Copper Mountain's entire liability of any infringement claim relating to the
Equipment.

9.   Limitation of Liability

     9.1  IN NO EVENT SHALL EITHER PARTY BE LIABLE TO THE OTHER PARTY FOR ANY
CONSEQUENTIAL, INCIDENTAL, SPECIAL OR INDIRECT DAMAGES OF ANY KIND, INCLUDING,
BUT NOT LIMITED TO, ANY LOST PROFITS, LOST SAVINGS, OR LOST DATA, ARISING FROM
OR RELATING TO THIS AGREEMENT, EVEN IF THE PARTY HAS BEEN ADVISED OF THE
POSSIBILITY OF SUCH DAMAGES. THE TOTAL CUMULATIVE LIABILITY OF EITHER PARTY TO
THE OTHER PARTY FOR ANY CLAIMS OR CAUSES OF ACTION ARISING FROM OR RELATING TO
THIS AGREEMENT, COPPER MOUNTAIN'S DELIVERY OF THE EQUIPMENT OR CUSTOMER'S USE OF
THE EQUIPMENT (WHETHER IN CONTRACT, IN TORT OR OTHERWISE) SHALL NOT EXCEED THE
AGGREGATE AMOUNT PAID TO COPPER MOUNTAIN UNDER THIS AGREEMENT.

     9.2  Customer understands that Copper Mountain's pricing is predicated on
the limitations of Copper Mountain's liability set forth in Section 9.1 and
acknowledges that Copper Mountain would not enter into this Agreement without
such limitations.

10.  Confidentiality

     The obligations of the parties with respect to "Confidential Information"
exchanged pursuant to this Agreement are as described in the Mutual Non-
Disclosure Agreement dated August 29, 1997 between the parties attached hereto
as Exhibit F.

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11.  Intellectual Property Rights

     Except for the right to use the System contemplated by this Agreement, the
delivery of the Equipment to Customer (a) does not convey to Customer or any
third party any intellectual property rights in the Equipment or System
Software, including, but not limited to, any patent, trademark, trade secret or
copyright, and (b) does not grant to Customer or any third party any license
under any patents or patent applications of Copper Mountain.  Customer shall
not, and shall not permit any third party to, disassemble or analyze the
physical construction of any Equipment (or any component thereof) for any
purpose.  Customer agrees not to remove or destroy any copyright, logo,
trademark, trade name, proprietary markings or confidentiality legends placed
upon or contained within the Equipment or System Software, its containers or any
related materials or documentation.  Customer agrees to comply with all legends
that appear on or in the Equipment and/or System Software or related materials
or documentation.

12.  Term and Termination

     12.1  Term.  This Agreement shall commence on the Effective Date and shall
expire on June 30, 2002, unless terminated earlier as provided herein (the
"Term").

     12.2  Termination for Default. Either party may terminate this Agreement if
the other party fails to perform any material obligation under this Agreement
and such failure is not cured within forty-five (45) days following written
notice of such failure to the defaulting party.

     12.3  Termination by Customer. Customer may terminate this agreement with a
sixty (60) day written notice to Copper Mountain at Customer's sole discretion.

     12.4  Effects of Termination. Upon termination of this Agreement for any
reason:

           (a)  for all Equipment for which Acceptance occurred before
termination, the full unpaid balance of the Purchase Price for such Equipment
shall become immediately due and payable so long as the termination did not
result from a default by Copper Mountain;

           (b)  for all Equipment delivered to Customer before termination for
which Acceptance has not yet occurred, Customer may either (i) return such
Equipment (and related documentation) to Copper Mountain in its original
condition and at the expense of the defaulting party (in which case Customer
shall not be required to pay the unpaid balance of the Purchase Price for such
Equipment), or (ii) keep such Equipment and pay the unpaid balance of the
Purchase Price for such Equipment; and

           (c)  Copper Mountain shall have no further obligation to deliver any
Equipment to Customer.

     12.5  Survival. The rights and obligations of the parties under Sections
7.1 through 7.4 (solely for the duration of the applicable Warranty Periods),
7.5, 7.6, 8, 9, 10, 11, 12.4, 12.5 and 16 shall survive termination of this
Agreement for any reason. Unless Copper Mountain terminates this Agreement
pursuant to Section 12.2, Section 13 shall also survive termination of this
Agreement for the time period specified therein.

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13.  Spare Parts

     13.1  Availability. Customer may purchase spare parts for the Equipment
from time to time at the same terms and conditions as set forth in this
Agreement. Copper Mountain shall use its best efforts to make available spare
parts (or compatible substitutes for such spare parts) for the Network Equipment
(but not for third party components or equipment) for a period of five years
after the Effective Date. If Copper Mountain discontinues manufacturing the
Network Equipment before the end of this five year period or discontinues
manufacturing Subscriber Equipment at any time, Copper Mountain shall notify
Customer at least six months in advance to permit Customer to procure a
sufficient stock of spare parts.

     13.2  Supply for Repairs. Customer shall be responsible for purchasing and
maintaining an adequate supply of spare parts to complete non-warranty repairs.
If Customer fails to maintain an adequate supply of spare parts, the time
allowed for Copper Mountain to complete non-warranty repairs shall be extended
by the amount of time needed for Copper Mountain to assemble and ship the
necessary spare parts to the location where the Network Equipment is installed
and operated.

14.  Product Additions

     As Copper Mountain develops and offers for sale and licenses to its
customers additional or next generation Network Equipment products and
Subscriber Equipment products during the Term, Copper Mountain shall offer such
Network Equipment for sale and license to Customer under this Agreement.  In
such case, the parties shall negotiate in good faith the pricing and other
appropriate terms and conditions relating specifically to such products in a
manner consistent with each party's obligations under this Agreement.

15.  Authority

     Each party represents and warrants to the other party that (a) such party
is duly organized, validly existing, and in good standing under the laws of the
place of its establishment or incorporation; (b) such party has taken all action
necessary to authorize it to enter into this Agreement and perform its
obligations under this Agreement; (c) this Agreement shall constitute the legal,
valid and binding obligations of such party; and (d) neither the execution of
this Agreement, nor the performance of such party's obligations hereunder, shall
conflict with, result in a breach of, or constitute a default under any
provision of the Articles of Incorporation, business license, Bylaws or similar
organizational documents of such party, or of any law, rule, regulation,
authorization or approval of any government entity, or of any agreement to which
it is a party or by which it is bound.

16.  General Provisions

     16.1  Force Majeure. Neither party shall be liable to the other party,
under this Agreement or otherwise, for any delay or lack of performance (other
than non-payment) resulting from an event of Force Majeure (as defined below).
If a Force Majeure event occurs, the party prevented from performing its
obligations under this Agreement shall inform the other party as soon as
possible and the time period for performance shall be extended by a period

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equivalent to the delay caused by the Force Majeure event plus any additional
period reasonably necessary to allow the prevented party to resume performance
of its obligations. The prevented party shall inform the other party as soon as
possible after the Force Majeure event ends. If the Force Majeure event lasts
for more than sixty (60) consecutive days after the initial notice of such
event, either party may terminate this Agreement with thirty (30) days written
notice. As used above, an event of "Force Majeure" means any act of God, war,
fire, typhoon, flood, earthquake, natural disasters, governmental action, labor
disruptions, materials shortages, or any other event beyond the reasonable
control of the prevented party.

     16.2  Assignment. Neither party may assign this Agreement or any right
under this Agreement, nor delegate any obligation under this Agreement, without
the other party's prior written consent (which shall not be unreasonably
withheld), except that either party may, with or without the other party's
consent, (a) assign this entire Agreement in connection with a merger,
reorganization, or sale of all or substantially all of its assets to a third
party; (b) assign part or all of this Agreement to one or more of its
affiliates; and (c) subcontract portions of its obligations under this Agreement
as long as the assigning party remains responsible for such obligations. Any
attempted assignment or delegation in contravention of this Section 16.2 shall
be void.

     16.3  Non-Waiver; Severability. Any delay or failure by either party to
exercise any right or remedy under this Agreement shall not constitute a waiver
of such right or remedy thereafter or of any other right or remedy. If any
provision of this Agreement is determined to be unenforceable, the remaining
provisions shall remain in full force and effect.

     16.4  Notices. All notices and other communications provided for hereunder
shall be in writing and shall be mailed by first-class, registered or certified
mail, postage paid, or delivered personally, by overnight delivery service or by
facsimile, computer mail or other electronic means, with confirmation of
receipt, addressed as follows:

If to Copper Mountain:        Copper Mountain Networks, Inc.
                              10145 Pacific Heights Boulevard, Suite 100
                              San Diego, California 92121
                              Attn: John A. Creelman
                              Fax No: (858) 410-7281

If to Customer:               NorthPoint Communications, Inc.
                              222 Sutter St., Suite 700
                              San Francisco, CA 94108
                              Attn: Steven Gorosh
                              Fax No:  (415) 403-4004

     Either party may by like notice specify or change an address to which
notices and communications shall thereafter be sent.  Notices sent by facsimile,
computer mail or other electronic means shall be effective upon confirmation of
receipt, notices sent by mail or overnight delivery service shall be effective
upon receipt or upon refusal of delivery, and notices given personally shall be
effective when delivered or when delivery is refused.

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     16.5  Publicity. Copper Mountain and Customer agree that neither party
shall originate any press release or other public announcement related to this
Agreement, written or oral, without the prior written consent of the other
party, except as required by law or a court order.

     16.6  Nondisclosure. Copper Mountain and Customer agree that either party
may disclose the existence of this Agreement, but neither party shall make any
disclosure relating to the terms of or performance under this Agreement to any
third party (other than their independent public accountants and attorneys)
without the prior written consent of the other party, except as required by law
or a court order.

     16.7  Governing Law and Venue. All matters arising in connection with this
Agreement or the enforcement or construction thereof shall be governed by
(without regard to conflict-of-laws provisions) and resolved in accordance with
the laws of the State of California. Copper Mountain and Customer each hereby
irrevocably (a) agrees that any suit, action or other legal proceeding arising
from or relating to this Agreement shall be brought in a court of competent
jurisdiction in San Francisco, California, which court shall have exclusive
jurisdiction over any controversy arising from or related to this Agreement; (b)
consents to the jurisdiction of such court in any such suit, action or
proceeding; and (c) waives any objection it may have to the laying of venue of
any such suit, action or proceeding in such court and waives any claim that any
such suit, action or proceeding has been brought in an inconvenient forum.
Service of process in any suit, action or proceeding may be made in any manner
permitted by law.

     16.8  Dispute Resolution. If any dispute arises between the parties
relating to the interpretation, breach or performance of this Agreement or the
grounds for the termination thereof, and the parties cannot resolve the dispute
within thirty (30) days of a written request by either party to the other party,
the parties agree to hold a meeting, attended by individuals with decision-
making authority regarding the dispute, to attempt in good faith to negotiate a
resolution of the dispute prior to pursuing other available remedies. If, within
sixty (60) days after such meeting, the parties have not succeeded in
negotiating a resolution of the dispute, such dispute shall be submitted to
final and binding arbitration under the then current commercial rules and
regulations of the American Arbitration Association (the "AAA") relating to
voluntary arbitrations. The arbitration shall be held in San Francisco,
California. The arbitration shall be conducted by one arbitrator, who is
knowledgeable in the subject matter at issue in the dispute and who will be
selected by mutual agreement of the parties or, failing such agreement, shall be
selected in accordance with AAA rules. Each party shall initially bear its own
costs and legal fees associated with such arbitration. The prevailing party in
any such arbitration shall be entitled to recover from the other party actual
attorneys' fees, costs and expenses incurred by the prevailing party in
connection with such arbitration. The decision of the arbitrator shall be final
and binding on the parties. The arbitrator shall prepare and deliver to the
parties a written, reasoned opinion conferring its decision. Judgment on the
award so rendered may be entered in any court having competent jurisdiction
thereof. Notwithstanding the foregoing, Copper Mountain shall have the
unequivocal right to obtain timely injunctive from a court of law pursuant to
Section 16.9.

     16.9  Injunctive Relief. Customer agrees that Customer's unauthorized
duplication, distribution or disclosure of any Confidential Information received
by Customer will actually and materially damage Copper Mountain and such damages
are difficult to calculate. In addition,

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notwithstanding any of the provisions of this Agreement, Copper Mountain shall
have the unequivocal right to obtain timely injunctive relief to protect its
intellectual property rights.

     16.10  Attorney's Fees. The prevailing party in any litigation between the
parties relating to this Agreement shall be entitled to recover its reasonable
attorney's fees and court costs, in addition to any other relief it may be
awarded, from the other party.

     16.11  Construction. The headings of sections and subsections of this
Agreement are for convenience only and shall not be construed to affect the
meaning of any provision of this Agreement. Any inconsistency between provisions
in this Agreement and the exhibits shall be resolved in favor of the main body
of this Agreement.

     16.12  Counterparts. This Agreement may be executed in counterparts, each
of which will be deemed an original and which together shall constitute one and
the same agreement.

     16.13  Entire Agreement; Modifications. This Agreement, together with the
exhibits attached hereto, constitutes the entire agreement between the parties
and supersedes all prior oral or written negotiations and agreements between the
parties with respect to the subject matter hereof. No modification, variation or
amendment of this Agreement shall be effective unless made in writing and signed
by the parties.

     In Witness Whereof, Copper Mountain and Customer have each caused this
Agreement to be executed by their duly authorized representatives.

Copper Mountain Networks, Inc.          NorthPoint Communications, Inc.

/s/  Richard S. Gilbert                 By: /s/  Tim Monahan
-----------------------                    ---------------------------
Richard S. Gilbert                      Name:  Tim Monahan
Chief Executive Officer                 Title: Vice President Finance & Planning


                                       12
<PAGE>

                                   EXHIBIT A
                        STANDARD COMMERCIAL PRICE LIST
                           COPPER MOUNTAIN NETWORKS


Product Name and Description                         Part No.       List Price
================================================================================
COPPEREDGE FAMILY
SYSTEMS

     CopperEdge 150 System                          800-010-10    [***]
         Chassis & Fan                              810-001-10
         SDSL Module-M (24 Port)                    820-021-10
         120VAC Power Module                        810-010-10
         Buffer Control Module                      810-020-10
         System Control Module/E                    810-100-10
         Documentation                              155-100-10

     CopperEdge 200 Basic System                    200-010-10    [***]
         Chassis & Backplane                        100-010-10
         DC Power Module                            100-510-10
         Buffer Control Module                      105-010-10
         System Control Module                      105-110-20
         Alarm Module                               100-130-10
         Documentation                              155-010-10

     CopperEdge 200 CopperBay System                200-020-10    [***]
         Chassis & Backplane                        100-010-10
         DC Power Module                            100-510-10
         Buffer Control Module                      105-010-10
         CopperBay Control Module                   105-120-10
         Documentation (CD-ROM)                     155-010-10
         Alarm Module                               100-130-10

CE150 SPARES (810)
     Chassis & Fan for CE 150                       810-001-10    [***]
     120VAC Power Module for CE150                  810-010-10    [***]
     Buffer Control Module for CE150                810-020-10    [***]
     System Control Module/E for CE150-200          810-100-10    [***]
     Fan Assembly for CE150                         810-030-10    [***]
CE150 OPTIONS (810)
     Mount kit for 23" rack for CE150               810-220-10    [***]
     SDSL Module-H (24 port)                        820-021-10    [***]
     CE150 System Software v1.0                     811-001-00    [***]
CE150 DOCUMENTATION (155)
     CE150 Documentation (Spare Set)                155-100-10    [***]
CE200 CHASSIS, POWER SUPPLIES (100)
     Chassis & Backplane
       (+fan tray & alarm panel) for CE200          100-010-10    [***]
     Redundant DC Power Module for CE200            100-510-10    [***]
     External AC Power Shelf and one Supply         100-610-10    [***]
     AC Power Supply for external shelf             100-611-10    [***]
     Alarm Panel for CE200                          100-130-10    [***]
     Fan Assembly for CE200                         100-020-14    [***]
CE200 PROCESSOR, BUFFER (105)
     System Control Module for CE200-200/32         105-110-20    [***]
     CopperBay Control Module for CE200             105-120-10    [***]
     Buffer Control Module for CE200                105-010-10    [***]
CE200 SOFTWARE (111)
     CE200 System Software v1.3                     111-001-30
     CE200 System Software v1.4                     111-001-40
     CE200 System Software v1.6                     111-001-60
     CE200 System software v2.0                     111-002-00
CE200 LINE CARDS / DSL MODULES (120)
     SDSL 30x Module (24 port)                      120-021-10    [***]
     IDSL Line Module (24 port)                     120-030-10    [***]
CE200 WAN I/O (130)
     V.35 WAN Module (2 port)                       130-020-10    [***]
     HSSI WAN Module                                130-030-10    [***]
     DS3 Frame Module                               130-035-10    [***]
     DS3 ATM Module                                 130-040-10    [***]
CE200 OTHER HARDWARE (140)
COPPERVIEW SOFTWARE (112)
     CopperView Element Manager v1.3                112-301-13    [***]
     CopperView Element Manager v1.4                112-301-14    [***]
     CopperView Element Manager v1.6                112-301-16    [***]
     CopperView AMS v2.0 (1-9 nodes)                112-400-20    [***]
     CopperView AMS v2.0 (10-49 nodes)              112-400-20    [***]
     CopperView AMS v2.0 (50-149 nodes)             112-400-20    [***]
     CopperView AMS v2.0 (150-399 nodes)            112-400-20    [***]
     CopperView AMS v2.0 (400-999 nodes)            112-400-20    [***]
     CopperView AMS v2.0 (1000-2499 nodes)          112-400-20    [***]
     CV AMS node upgrade (1-9 to 10-49)             112-401-20    [***]
     CV AMS node upgrade (10-49 to 50-149)          112-401-20    [***]
     CV AMS node upgrade (60-149 to 150-399)        112-401-20    [***]
     CV AMS node upgrade (150-399 to 400-999)       112-401-20    [***]
     CV AMS node upgrade (400-999 to 1000-2499)     112-401-20    [***]
DOCUMENTATION (155)
     CE200 Documentation set                        155-010-10    [***]
     CopperView EMS documentation (hardcopy)        155-020-20    [***]
     DSL Troubleshooting Guide                      155-030-10    [***]
CABLES
     DC Power Cable (10 feet)                       160-010-10    [***]
     DSL Connector Cable (25 feet)                  160-015-05    [***]
     DSL Connector Cable (10 feet)                  160-015-10    [***]
     DSL Connector Cable (6 feet)                   160-015-15    [***]
     DSL Connector Cable (3 feet)                   160-015-20    [***]
     Ethernet Cable (10 feet)                       160-020-10    [***]
     RS232 Craft Interface Cable (6 feet)           160-021-10    [***]
     V.35 Cable (25 feet)                           160-030-10    [***]
     HSSI Cable (25 feet)                           160-035-10    [***]
OTHER (170)
     CE200 Mount kit for 23" rack                   170-010-10    [***]
COPPERROCKET FAMILY
     CopperRocket 201 SDSL                          700-030-30    [***]
     CopperRocket 201 SDSL (RJ11-RJ45)              700-030-31    [***]
     CopperRocket 201 IDSL                          700-050-10    [***]
     CopperRocket 201 IDSL (RJ11-RJ45)              700-050-11    [***]
     CopperRocket 201 SDSL CCA Board                700-930-30    [***]
     CopperRocket 201 IDSL CCA Board                700-950-10    [***]


[***] CONFIDENTIAL TREATMENT REQUEST(ED)







<PAGE>

                                   EXHIBIT B

                      MINIMUM VOLUME COMMITMENT; DISCOUNT

Minimum Volume Commitment

Customer hereby agrees to place two (2) non-cancelable Blanket Purchase Orders
fifteen (15) days prior to the beginning of each calendar quarter such that the
first Blanket Purchase Order (A) is for an amount equal to [***] of the most
recent Forecast (the initial version of which is attached as Exhibit C (the
"Initial Forecast")), for the first quarter contained in such Forecast, and such
that the second Blanket Purchase Order (B) is for an amount equal to [***] of
such Forecast for the second quarter contained in such Forecast. Fifteen (15)
days prior to the beginning of each subsequent quarter, the Customer shall issue
two (2) additional non-cancelable Purchase Orders for amounts, which combined
with Blanket Purchase Orders issued previously, equal to (A) [***] of the most
recent Forecast for the first quarter contained in such Forecast, and such that
the second Blanket Purchase Order (B) is for an amount equal to [***] of such
Forecast for the second quarter contained in each such Forecast. This issuance
of non-cancelable Blanket Purchase Orders will be replicated through the term of
this contract on a quarterly basis. Additionally, all non-cancelable Blanket
Purchase Orders shall be credited for the applicable quarter for all standard
Purchase Orders, outlining the specific Equipment to be purchased in any
quarter, issued by the Customer to Copper Mountain.

Discount

In exchange for the purchase and receipt of the Minimum Volume Commitment by
Customer, Copper Mountain hereby grants to Customer a discount to the purchase
price (as set forth in Exhibit A) of [***] on any Equipment purchased by
Customer during the Term, with the exception of SDSL Line Cards for which the
discount to the purchase price shall be [***].


[***]  CONFIDENTIAL TREATMENT REQUEST(ED)

<PAGE>

                                   EXHIBIT C

                               INITIAL FORECAST

<TABLE>
<CAPTION>
                           Jul-99  Aug-99   Sep-99   Oct-99   Nov-99   Dec-99   Jan-00   Feb-00   Mar-00   Apr-00   May-00   Jun-00
<S>                        <C>     <C>      <C>      <C>      <C>      <C>      <C>      <C>      <C>      <C>      <C>      <C>
GRAND TOTAL

   Base System                                                         [***]
   Redundant Power                                                     [***]
   Buffer Module                                                       [***]
   SCM                                                                 [***]
   CopperBay SCM                                                       [***]

   24 Port SDSL LC                                                     [***]
   24 Port IDSL LC                                                     [***]
   V.35                                                                [***]
   DS3 Frame                                                           [***]
   DS3 ATM                                                             [***]

   23" Mounting Kit                                                    [***]
   CR201 SDSL (RJ45-RJ11)                                              [***]
   CR201 IDSL (RJ45-RJ11)                                              [***]

   TOTAL
</TABLE>

[***] CONFIDENTIAL TREATMENT REQUEST(ED)


<PAGE>

                                   EXHIBIT D

                       PRODUCT MILESTONE SPECIFICATIONS

1.   DS3 ATM WAN Interface Module Improvements

General Availability Date:  [***]
The existing Copper Mountain DS3 ATM WAN module shall include the following
feature improvements:

 .    Performance shall be increased to at least [***] cells per second.
 .    The [***] support shall be extended.
 .    The [***] disable shall be supported.

2.   G.Lite Line Card for CE200

General Availability Date:  [***]

 .    The Copper Mountain G.Lite line card shall have [***] ports and conform to
     the G.Lite standard.
 .    Copper Mountain shall interoperate with mutually agreed upon third party
     G.Lite CPE vendors.
 .    Copper Mountain [***].

3.   CopperBay Chassis Aggregation with Support of two or more CE200's

General Availability Date:  [***]

 .    The ability to aggregate [***] CE200 chassis shall be supported. This will
     allow a single WAN trunk to be used to aggregate [***] CE200 chassis. The
     addition of CopperBay equipment and correct software version shall be
     required to support this enhancement. The CopperBay AMS shall provide a
     single management interface to manage the multi-shelf complex.

4.   [***]

General Availability Date:  [***]

 .    [***]
 .    [***]
 .    Copper Mountain shall perform testing with one or two third party derived
     voice equipment suppliers to verify the operation of the [***].


[***] CONFIDENTIAL TREATMENT REQUEST(ED)
<PAGE>

5.   [***]

General Availability Date:  [***]

 .    Copper Mountain shall produce a SDSL DSU capable [***]

6.   EMS API to Third Party Management System

Product Requirements Specification Date:  [***]

 .    Copper Mountain shall work with Customer (and any third party providers
     designated by Customer and mutually agreeable to Copper Mountain) to
     generate a Product Requirements Specification (the "Specification") no
     later than [***]. Both parties agree to amend the Agreement within
     thirty (30) days following the completion of the Specification. Such
     amendment shall incorporate all aspects of product or software
     functionality and their related timetable as set forth in the
     Specification.


[***]  CONFIDENTIAL TREATMENT REQUEST(ED)
<PAGE>

                                   EXHIBIT E

                         SUBSCRIBER EQUIPMENT WARRANTY

1.   Limited Warranty

     During the applicable Warranty Period for Subscriber Equipment, Copper
Mountain warrants to Customer that the Subscriber Equipment (excluding Pre-
Production Units) shall be free from material defects in material and
workmanship. This warranty is not transferable to any third party, including,
but not limited to, any subsequent purchaser, owner, lessee or licensee of
Subscriber Equipment.

2.   Warranty Claims

     All Subscriber Equipment returned under warranty must be returned to a
Copper Mountain authorized repair facility (an "Authorized Service Center").

3.   Exclusive Remedy

     If Customer returns Defective Subscriber Equipment to an Authorized Service
Center within the applicable Warranty Period and Copper Mountain reasonably
determines that such Subscriber Equipment is in fact Defective, Copper Mountain
shall, as Customer's sole and exclusive remedy for breach of warranty and at
Copper Mountain's option, either (a) repair the Defective Subscriber Equipment,
(b) replace the Defective Subscriber Equipment with a new or a rebuilt unit,
which may contain refurbished parts of similar quality and functionality, or (c)
if Copper Mountain determines that it is unable to repair or replace the
Defective Subscriber Equipment, refund the purchase price for the Defective
Subscriber Equipment. After the applicable Warranty Period, Customer must pay
all shipping, parts and labor charges. Copper Mountain's warranty service does
not include customer instruction or the cost of installation, removal or
reinstallation of Subscriber Equipment.

4.   Exclusions

     The warranty set forth above does not apply to: (a) Subscriber Equipment
that has been installed, repaired, maintained or modified other than in
compliance with the documentation furnished to Customer; (b) Subscriber
Equipment that has been subjected to misuse (including use in conjunction with
electrically or mechanically incompatible hardware), abuse, accident, physical
damage, abnormal operation, improper handling, neglect, exposure to fire, water
or excessive moisture or dampness or extreme changes in climate or temperature;
(c) cosmetic damage; (d) Subscriber Equipment on which warranty stickers or
serial numbers have been removed, altered, or rendered illegible; (e) damage as
a result of fire, flood, acts of God or other acts which are not the fault of
Copper Mountain and which the Subscriber Equipment is not specified to tolerate,
including damage caused by mishandling, shipping and blown fuses; or (f) any
Subscriber Equipment that has been opened, repaired, modified or altered by
anyone other than Copper Mountain or a Copper Mountain Authorized Service
Center.
<PAGE>

                                   EXHIBIT F

                        MUTUAL NON-DISCLOSURE AGREEMENT


     THIS AGREEMENT is made as of August 29, 1997 between NORTHPOINT
COMMUNICATIONS, INC., a Delaware corporation (the "Company") and Copper Mountain
                                                   -------
Network ("Third Party").

     1.  Purpose.  The Company and Third Party wish to explore a business
         -------
possibility in connection with which each may disclose its Confidential
Information to the other (the "Relationship").
                               ------------

     2.  Definition of Confidential Information.  "Confidential Information"
         --------------------------------------    ------------------------
means any information, technical data, or know-how, including, but not limited
to, that which relates to research, product plans, products, services,
customers, markets, software, developments, inventions, processes, designs,
drawings, engineering, hardware configuration information, marketing or finances
of the disclosing party, which Confidential Information is designated in writing
to be confidential or proprietary, or if given orally, is confirmed promptly in
writing as having been disclosed as confidential or proprietary. Confidential
Information does not include information, technical data or know-how which (i)
is in the possession of the receiving party at the time of disclosure as shown
by the receiving party's files and records immediately prior to the time of
disclosure; or (ii) prior to or after the time of disclosure becomes part of the
public knowledge or literature, not as a result of any improper inaction or
action of the receiving party, or (iii) is approved by the disclosing party, in
writing, for release.

     3.  Non-Disclosure of Confidential Information.  Each party agrees not to
         ------------------------------------------
use any Confidential Information disclosed to it by the other party for its own
use or for any purpose except to carry out discussions concerning, and the
undertaking of, the Relationship. Neither party will disclose any Confidential
Information of the other party to third parties or to employees of the party
receiving Confidential Information, except employees who are required to have
the information in order to carry out the discussions regarding the
Relationship. Each party will have or has had employees to whom Confidential
Information of the other party is disclosed or who have access to Confidential
Information of the disclosing party sign a nondisclosure or similar agreement in
content substantially similar to this Agreement. Each party agrees that it will
take all reasonable measures to protect the secrecy of and avoid disclosure or
use of Confidential Information of the other party in order to prevent it from
falling into the public domain or the possession of persons other than those
persons authorized under this Agreement to have any such information. Such
measures shall include the highest degree of care that the receiving party
utilizes to protect its own Confidential Information of a similar nature. Each
party agrees to notify the other in writing of any misuse or misappropriation of
Confidential Information of the disclosing party which may come to the receiving
party's attention.

     4.  Return of Materials.  Any materials or documents which have been
         -------------------
furnished by one party to the other in connection with the Relationship will be
promptly returned by the receiving party, accompanied by all copies of such
                                                         ---
documentation, within ten (10) days after (i) the Relationship has been
terminated or (ii) the written request of the disclosing party.

     5.  Patent or Copyright Infringement.  Nothing in this Agreement is
         --------------------------------
intended to grant any rights under any patent or copyright of either party, nor
shall this Agreement grant either party any rights in or to the other party's
Confidential Information, except the limited right to review such Confidential
Information in connection with the proposed Relationship between the parties.

     6.  Term.  The foregoing commitments of each party shall survive any
         ----
termination of the Relationship between the parties, and shall continue for a
period terminating on the later to occur of (i) five (5) years following the
date of this Agreement of (ii) three (3) years from the date on which
Confidential Information is disclosed under this Agreement.

     7.  Miscellaneous.  This Agreement shall be binding upon and for the
         -------------
benefit of the undersigned parties, their successors and assigns, provided that
Confidential Information of the disclosing party may not be assigned without the
prior written consent of the disclosing party. Failure to enforce any provision
of this Agreement by a party shall not constitute a waiver of any term hereof by
such party.

     8.  Governing Law.  This Agreement shall be governed by and construed and
         -------------
enforced in accordance with the internal laws of the State of California, and
shall be binding upon the parties to this Agreement in the United States and
worldwide.

     9.  Remedies.  Each party agrees that its obligations provided in this
         --------
Agreement are necessary and reasonable in order to protect the disclosing party
and its business, and each party expressly agrees that monetary damages would be
inadequate to compensate the disclosing party for any breach by the receiving
party of its covenants and agreements set forth in this Agreement. Accordingly,
each party agrees and acknowledges that any such violation or threatened
violation will cause irreparable injury to the disclosing party and that, in
addition to any other remedies that may be available, in law, in equity or
otherwise, the disclosing party shall be entitled to obtain injunctive relief
against the threatened breach of this Agreement or the continuation of any such
breach by the receiving party, without the necessity of proving actual damages.


                                       NORTHPOINT COMMUNICATION, INC.


                                       By: /s/  Michael Malaga
                                          ---------------------------
                                       Title: Chief Executive Officer


                                       By: /s/ Illegible Kelly
                                          ---------------------------

                                       Title: VP Sales