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                                                                   Exhibit 10.21

                       International Services Agreement

THIS INTERNATIONAL SERVICES AGREEMENT (the "Agreement") is entered into as of
April 7th, 2000 (the "Effective Date") between iAsiaWorks Corporation
("iAsiaWorks"), a California corporation with its principal offices at 2000
Alameda de las Pulgas, Ste. 125, San Mateo, California 94403, and Digital Island
("Client"), a Delaware corporation with its principal offices at 45 Fremont St.
Suite 1200, San Francisco, California 94105.

WHEREAS, Digital Island desires to transmit Internet traffic over iAsiaWorks'
telecommunications network in Asia, the Philippines and New Zealand (the
"Territory") and obtain the benefit of iAsiaWorks' related maintenance and other
services and iAsiaWorks desires to service Digital Island's traffic;

IT IS AGREED, in consideration of the covenants set forth below, as follows:

1.     iAsiaWorks' Services.

iAsiaWorks will provide to Client Internet Protocol ("IP")-capable services as
described in Attachment I, including its Exhibit A, attached hereto and
             ------------                ---------
incorporated herein by this reference (collectively, the "Services") to transmit
Client's Internet traffic over iAsiaWorks' backbone network (the "Network")
and/or other networks in the Territory with which iAsiaWorks maintains direct
connections from time to time. If necessary, the Network will support Client's
use of Border Gate Protocol routing to reach the Network.

2.     Clients' Obligations. iAsiaWorks' performance hereunder is conditioned
upon Client's performance of or compliance with the following:

2.1  Client shall provide Domain Name Server ("DNS") registrations and all DNS
name service functions for itself and its customers. Client shall give
iAsiaWorks reasonable prior written notice of (i) Client's need for additional
IP network numbers or (ii) changes in existing routing information.

2.2  At Client's sole expense, Client will connect its own computer hardware and
other telecommunications equipment (collectively, the "Equipment") directly to
the Network and, as between the parties hereto, shall be fully and solely
responsible for the Equipment and any damage thereto and the installation and
maintenance of full connectivity between the Equipment and the Network,
including the addition from time to time of any and all Equipment required to
support the then-current volume of Client's Internet traffic over the Network.
At Client's request, iAsiaWorks will assist Client in the maintenance and repair
of its Equipment for fees to be mutually agreed or as otherwise set forth in
Exhibit A to Attachment I; provided that iAsiaWorks will not be liable to Client
---------    ------------
for any damage to the Equipment other than to the extent arising out of
iAsiaWorks gross negligence or misconduct.

2.3  The Client may only use the Services and/or access the Network for the
purposes expressly identified herein. Any other use or access is expressly
prohibited, including but not limited to any unlawful or illegal use by Client
in any jurisdiction where a transmission commences, transits or is terminated or
any other jurisdiction asserting control over any such transmission, a breach by
Client of any copyright, privacy, libel or obscenity laws, email spamming and/or
bulk transmission of messages to Internet users, service providers and/or
newsgroups, and unsolicited e-mail.

2.4  Client is wholly responsible for insuring the safety and security of the
Equipment and its connection to the Network and must restrict access thereto and
otherwise safeguard the operation thereof with the same degree of care which
employs to protect its own network. At a minimum, Client must promptly notify
iAsiaWorks in writing of any breach of security involving the Equipment,
Client's own network and/or the connection to the Network.

     2.4.1  The Client will be liable for, and will indemnify and defend
iAsiaWorks against, any claims arising out or related to any demonstrable breach
of security on the Network resulting from the acts or omissions of Client or its
employees, agents and/or users and other customers.

2.5  Client is wholly responsible for obtaining a complete copy of adhering to
and fully complying with the People's Republic of China's ("PRC") "Appropriate
Use" policies with respect to Internet transmissions and content filtering,
including policies concerning the filtering and exclusion of pornography, anti-
government content and

[*]-Certain Information in this exhibit has been omitted and filed separately
with the commission.  Confidential treatment has been requested with respect to
the omitted portions.





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encrypted content. Client will be liable for, and will indemnify and defend
iAsiaWorks against, any claims arising out of or related to Client's failure to
fulfill its obligations hereunder, including any claims made or actions
instituted by the PRC to the extent such claims result from the actions of
Client or its employees, agents and/or users and other customers.

3.     Term of the Agreement.

This Agreement will commence as of the Effective Date and run for 12 full
calendar months thereafter (the "Initial Term") unless terminated as set forth
below. Upon expiration of the Initial Term, the Agreement will automatically
renew for successive 12-month periods until terminated (the Initial Term and all
renewal terms, collectively, the "Term").

Client may cancel the Services and terminate this Agreement on 30 days' prior
written notice to iAsiaWorks; provided that, on any cancellation more than 30
days prior to the end of the Initial Term, Client will pay iAsiaWorks an amount
equal to 50% of the Monthly Fees which would have been due for the remainder of
the Initial Term (the "Termination Payment"). Following the Initial Term, Client
may terminate this Agreement on 30 days' prior written notice with any
obligation to remit the Termination Payment.

iAsiaWorks may cancel the Services and terminate the Agreement on 90 days' prior
written notice to Client and, on such a termination, will refund to Client
prorated payments and deposits returned to iAsiaWorks by any third party, if
any. In addition, on one party's material breach of this Agreement, the other
party may terminate this Agreement on 30 days' written notice unless the
defaulting party cures such breach within that 30-day period. If Client
terminates this Agreement on iAsiaWorks uncured material breach, Client will not
be obligated to remit the Termination Payment.

       On any termination of this Agreement, Client shall pay iAsiaWorks all
Service Fees and other amounts due and owing as of the termination date. The
following provisions will survive termination, cancellation or expiration of
this Agreement: 2.3, 2.4, 2.4.1, 4.5, 6.2 through 6.5 and 7 through 9.

4.     Disclaimer of Warranty; Limitation of Liability; Indemnity.
4.1  iASIAWORKS MAKES NO WARRANTIES OF ANY KIND, WHETHER EXPRESS OR IMPLIED,
ORAL OR WRITTEN, WITH RESPECT TO THE NETWORK, THE OPERATION OR MAINTENANCE
THEREOF OR THE SERVICES PROVIDED HEREUNDER AT ANY TIME AND FROM TIME TO TIME,
iASIAWORKS DISCLAIMS (1) ANY WARRANTY OF MERCHANTABILITY OR FITNESS FOR A
PARTICULAR PURPOSE, (2) ANY WARRANTY THAT THE NETWORK OR iASIAWORKS' EQUIPMENT
OR SOFTWARE THEREON IS ERROR-FREE, WILL OPERATE WITHOUT INTERRUPTION OR IS
COMPATIBLE WITH ALL OTHER NETWORKS OR EQUIPMENT AND SOFTWARE CONFIGURATIONS, AND
(3) ANY WARRANTY THAT THE NETWORK WILL OPERATE WITHOUT INTERRUPTION.

       4.1.1  iASIAWORKS WILL NOT BE RESPONSIBLE OR LIABLE FOR ANY INDIRECT,
INCIDENTAL, SPECIAL OR CONSEQUENTIAL DAMAGES, INCLUDING, WITHOUT LIMITATION, (1)
THE LOSS OF PROFITS OR REVENUE (2) THE LOSS OF DATA OR INFORMATION, (3) THE COST
OF PROCUREMENT OF SUBSTITUTE SERVICES , AND (4) COSTS OR DAMAGES RESULTING FROM
DELAY, NON-DELIVERIES, MISDELIVERIES, SERVICE INTERRUPTIONS OR OTHER LOSS OF
ACCESS TO OR USE OF THE NETWORK, INCURRED BY EITHER PARTY OR ANY THIRD PARTY IN
CONNECTION WITH THIS AGREEMENT AND CLIENT'S USE OF AND ACCESS TO THE NETWORK,
WHETHER IN AN ACTION IN CONTRACT, TORT, BASED ON A WARRANTY OR OTHERWISE, EVEN
IF THE OTHER PARTY OR ANY OTHER PERSON HAS BEEN ADVISED OF THE POSSIBILITY OF
SUCH DAMAGES. IN NO EVENT SHALL iASIAWORKS' LIABILITY HEREUNDER EXCEED THE
AGGREGATE FEES PAID BY CLIENT HEREUNDER IN THE CALENDAR QUARTER IMMEDIATELY
PRECEDING THE DATE OF ANY CLAIM MADE BY CLIENT HEREUNDER.

       4.1.2  THE USE OF ANY INFORMATION OBTAINED VIA iASIAWORKS' NETWORK OR
SERVICES IS AND WILL BE AT THE SOLE RISK OF CLIENT AND ITS USERS AND OTHER
CUSTOMERS. CLIENT EXPRESSLY ACKNOWLEDGES AND AGREES THAT (I) IASIAWORKS

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EXERCISES NO CONTROL WHATSOEVER OVER THE CONTENT, NATURE OR SCOPE OF THE
INFORMATION PASSING OVER ITS NETWORK AND (II) IASIAWORKS WILL NOT BE RESPONSIBLE
IN ANY WAY FOR THE ACCURACY, COMPLETENESS OR QUALITY OF INFORMATION OBTAINED
OVER THE NETWORK OR OTHERWISE THROUGH ITS SERVICES. CLIENT SHALL INDEMNIFY AND
DEFEND IASIANETWORKS AGAINST ANY CLAIMS BROUGHT AGAINST IASIAWORKS BY ANY OF
CLIENT'S USERS OR CUSTOMERS WITH RESPECT TO ANY INFORMATION OBTAINED OVER THE
NETWORK OR THROUGH THE SERVICES.

4.2  In addition to, and without limitation of, the indemnities set forth in
Sections 2.4.1, 2.5, 4.1.2 and 6.4.2 above, Client will indemnify, defend and
hold iAsiaWorks harmless from and against any and all claims, losses,
liabilities and actions to the extent arising out of (i) the Client's breach of
this Agreement, (ii) Client's business operations, including the provision of
Internet services to its own users and customers and the operation of a
telecommunications network, and (iii) any unlawful or illegal use of the Network
or related Services by Client's users or customers.

4.3  iAsiaWorks will defend, indemnify and hold Client and its directors,
officers, employees, agents and subcontractors harmless from and against any and
all third party suits, actions and proceedings, claims, liabilities, losses,
expenses (including reasonable attorney's fees), damages and costs (collectively
referred to herein as "Claims") arising out of: (a) any negligent or intentional
act of iAsiaWorks or its directors, officers, employees, agents or
subcontractors or (b) any breach by iAsiaWorks' of Section 8 below except to the
extent that (i) Client is obligated to indemnify iAsiaWorks from and against any
such Claim hereunder and/or (ii) such Claim arises out of Client's negligent or
intentional acts or omissions.

5.     Scheduled Interruptions in Service.
Although, as clearly set forth in Section 4 above, iAsiaWorks provides Client
with Services and use of and access to the Network on an "as is" basis without
warranty of any kind, iAsiaWorks will use reasonable commercial efforts to
maintain the Network in a manner that minimizes errors and interruptions in the
course of providing the Services. Client acknowledges that, in the ordinary
course of business, the Network or related Services may be temporarily
unavailable due to scheduled maintenance, either by iAsiaWorks or by a third
party provider or for any other reason. However, iAsiaWorks will use reasonable
commercial efforts to provide seven days prior written notice of any scheduled
Network or Services disruption. Should such a disruption arise out of the
failure of any equipment or services wholly or majority owned and operated by
iAsiaWorks and continue for more than 24 hours, Client may immediately terminate
this Agreement without any Termination Payment; provided that Client will remit
payment to iAsiaWorks for Services rendered through the termination date and
further provided that, on such a termination, iAsiaWorks will refund to Client
prorated payments and deposits returned to iAsiaWorks by any third party, if
any.

6.     Payments; Taxes.
6.1  iAsiaWorks shall assist Client in the connection of the Equipment to the
Network at the sites listed in Attachment I. Excluding amounts previously
                               ------------
remitted by Client to iAsiaWorks hereunder, applicable per-installation charges
will be payable upon completion of each installation. iAsiaWorks will invoice
Client for such charges within three business days after the completion of each
installation hereunder with payment due net 30 days thereafter.

6.2  Monthly Service fees (the "Service Fees") will be invoiced in advance on
the first of each month in which Services will be rendered, commencing in the
first month after an iAsiaWorks hub and functioning circuit have been connected
to the Equipment and are operational. If Client fails to notify iAsiaWorks
within three business days after installation that the connection is non-
operational, iAsiaWorks may commence invoicing for its Service Fees. The first
month of operation will be billed in arrears on a pro rata basis with the
                                                  --------
Service Fees therefor included in iAsiaWorks' invoice for the Service Fees for
the next month.

6.3  Payment of all Service Fees and, except as set forth above, other amounts,
if any, due hereunder, is due in U.S. dollars net 30 days after date of invoice,
payable via wire transfer or other mutually agreed upon method in accordance
with instructions provided by iAsiaWorks. iAsiaWorks may charge a late fee equal
to the lesser of 12% per annum or the maximum interest rate permitted by law on
undisputed amounts not paid when due for as long as such amount remains unpaid.
However, if Client disputes any invoiced amount in good faith, it must submit to
iAsiaWorks, within 45 days following the date of invoice (the "Challenge
Period"), full payment of the undisputed

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portion of the invoice and written documentation identifying and substantiating
the disputed amount. Any amount not disputed in writing within the Challenge
Period will be deemed accepted for payment in full by Client.

6.4  Notwithstanding anything set forth above or in Attachment 1, Client
                                                    ------------
acknowledges and agrees that China Telecom or any successor entity and any third
party in the PRC or any successor entity (the "Third Party") through which
iAsiaWorks obtains access to telecommunications circuits in the People's
Republic of China ("PRC") require monthly deposits against future service.
Accordingly, within 10 business days of the Effective Date, Client will remit
the amount set forth in Attachment I (the "PRC Funds") in payment of the first
                        ------------
month's Services in the PRC and two separate one-month security deposits in the
amounts set forth therein. iAsiaWorks will promptly remit the PRC Funds to the
Third Party for disbursement as appropriate to China Telecom.*

     6.4.1  At such time as Client elects to terminate the services provided by
China Telecom for any reason Client will promptly notify iAsiaWorks in writing
and iAsiaWorks will take the actions necessary to terminate such services.
Following termination of the services, assuming that Client is current in the
payment of all Service Fees and in compliance with all rules and regulations
imposed by China Telecom, the Third Party or any other successor or replacement
entity, iAsiaWorks will refund to Client all PRC Funds, including any prorated
payments and deposits, returned to iAsiaWorks, if any, or, at Client's option,
apply those Funds to future Service Fees.

     6.4.2  Client acknowledges and agrees that, with respect to the payment of
the PRC Funds and the arranging for telecommunications services to be provided
in the PRC, iAsiaWorks is acting solely as Client's agent and will bear no
liability or responsibility for the PRC Funds (other than on iAsiaWorks'
misappropriation thereof), China Telecom's provision of telecommunications
services and circuits in the PRC, the repayment of each of the two separate
security deposits by the PRC and the Third Party, respectively, or any other
related matter. Client will indemnify and defend iAsiaWorks against any claims
arising out iAsiaWorks' acts or omissions on Client's behalf under this Section
6.4 and acknowledges that it is fully liable therefor.

6.5  All Service Fees and other amounts quoted to the Client herein are
exclusive of any federal, state, municipal or other governmental taxes, duties,
fees, tariffs or withholding obligations now or hereafter imposed on Client's
use of the Network and related Services. Such taxes, if any, other than taxes
assessed against iAsiaWorks' net income, will be invoiced separately by
iAsiaWorks and paid by Client or Client shall provide iAsiaWorks and/or the
appropriate authority with proof of exemption. If, in any international
jurisdiction, taxes must be withheld on any amounts to be paid by Client to
iAsiaWorks, the Client shall promptly notify iAsiaWorks, and, unless instructed
otherwise by iAsiaWorks, may deduct such taxes from the amount due and remit the
taxes to the appropriate authority.

7.     Assignment

Neither party may assign this Agreement or any of its rights or obligations
hereunder without the other party's prior written consent other than to an
affiliated entity or upon the merger, acquisition or sale of all or
substantially all the assets of the assigning party; provided that the assigning
party will promptly notify the other party of such an assignment and further
provided that provided that each and every assignee hereunder must agree in
writing to be bound by all the terms and conditions hereof.

8.     Confidential Information; Publicity.

Each party acknowledges that (i) all information relating to the business and
operations of the other party which it learns or has learned during or prior to
the term of this Agreement, including all operation data pertaining to the
Client's use of the access to the Network and the Services, including routing
data and outage information, (ii) the terms and conditions of this Agreement and
(iii) all information disclosed in or arising out of any dispute or arbitration
between the parties, including the outcome thereof, is and will be the valuable,
confidential and proprietary information of the disclosing party. The receiving
party will maintain all confidential information disclosed hereunder by the
disclosing party in confidence and will not disclose such information to any
third party other than those of its employees, contractors, agents or
representatives with a need to know such information; provided that each such
employee or contractor must have executed a confidentiality agreement or be
otherwise bound by the obligations of the receiving party hereunder. The
receiving party will safeguard the confidential information with the same degree
of care which it uses to protect its own confidential information.

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This Section will not apply to any information which (i) is already lawfully in
the receiving party's possession (unless received pursuant to a nondisclosure
agreement); (ii) is or becomes generally available to the public through no
fault of the receiving party; (iii) is disclosed to the receiving party by a
third party who may transfer or disclose such information without restriction;
(iv) is required to be disclosed by the receiving party as a matter of law or
judicial or governmental order; provided that the receiving party will use all
reasonable efforts to provide the disclosing party with prior notice of such
disclosure so that the disclosing party may seek a protective order therefor;
and (v) is independently developed by the receiving party without any use of
confidential information. Each party acknowledges that any breach of this
Section by a receiving party will irreparably harm the disclosing party and on
any such breach, the disclosing party shall be entitled to promptly seek
injunctive relief in addition to any other remedies which it may have at law or
in equity.

Further to the foregoing, other than Client's right to identify iAsiaWorks to
Client's users and customers as an Internet service provider providing Services,
neither party shall publicize the existence of this Agreement without the other
party's prior written consent except as required by law. All press releases and
related marketing materials and other communications relating to this Agreement
or the Services provided hereunder shall be subject to the reasonable and timely
pre-approval of each party.

9.     General

9.1  Client and iAsiaWorks are entering into this Agreement as independent
parties and nothing herein shall be construed to create a partnership, joint
venture or agency relationship between the parties except as expressly set forth
in Section 6.4 with respect to matters concerning the PRC. Neither party will
have any authority to enter into agreements of any kind on behalf of the other
party or to bind or obligate the other party in any manner to any third party.

9.2  Notices required to be given pursuant to this Agreement shall be effective
when received, and shall be sufficient if given in writing, hand-delivered, sent
by telefax with confirmation of receipt, sent by First Class Mail, return
receipt requested (for all types of correspondence), postage prepaid, or sent by
overnight courier service and addressed as first set forth above.

9.3  This Agreement and the rights of the parties hereunder will be governed by
and interpreted in accordance with the laws of the State of California, without
reference to its conflict of law rules, and applicable federal law. The United
Nations Convention On Contracts For The International Sale Of Goods will not
govern or apply to this Agreement. All disputes arising out of or in connection
with this Agreement will be referred to and finally resolved by binding
arbitration in accordance with the rules of the International Chamber of
Commerce consistent with California and federal law. The arbitration proceedings
will be conducted in San Francisco, California in English before a three-person
panel knowledgeable about telecommunications, consisting of one arbitrator
selected by Client, one selected by iAsiaWorks and one arbitrator selected by
the other two arbitrators. The arbitrator may award any legal or equitable
remedy and may, in his discretion, require one party to pay the costs of the
arbitration as well as the fees and expenses, including reasonable attorneys'
fees, of the other party. In the absence of any such ruling, each party shall
bear its own costs in connection with an arbitration proceeding hereunder and
the parties shall share the costs of the arbitration equally.

9.4  Neither party shall be in default hereunder if its failure to perform any
of its obligations, excluding all payment obligations, is caused solely by
supervening conditions beyond that party's control, including acts of God, civil
commotion, strikes, labor disputes, third party telecommunications network
problems or down-time and governmental demands or requirements.

9.5  This Agreement including Attachment 1, (i) embodies the final, complete and
exclusive understanding between the parties, (ii) replaces and supercedes all
previous oral or written agreements, understandings or arrangements between the
parties, (iii) may be signed in counterparts, each of which shall be an original
and all of which shall constitute one and the same document and (d) may only be
amended in a writing signed by an authorized officer of each party hereto. The
failure of either party to enforce the provisions of this Agreement shall not be

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deemed a waiver of such provisions or of the right of such party thereafter to
enforce such provisions or any other provisions hereof. If any provision of this
Agreement is held invalid or unenforceable by a court of competent jurisdiction,
the remaining provisions will remain in full force and effect and the parties
shall negotiate in good faith a substitute a valid and enforceable provision
which most nearly effects the parties' intent in entering into this Agreement

IN WITNESS WHEREOF, the parties have entered into this Agreement as of the
Effective Date.



IASIAWORKS CORPORATION              DIGITAL ISLAND, INC.


/s/ Jonathan Beizer                 /s/ J.W. Bendrick
___________________________         ------------------------------
Signature                           Signature

Jonathan Beizer                     J.W. Bendrick
___________________________         ------------------------------
Name                                Name

CFO                                 Director of Carrier Relations
___________________________         ------------------------------
Title                               Title

4/7/00                              4/7/00
___________________________         ------------------------------
Date                                Date

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                                 ATTACHMENT I



[*] -- Certain information on this page has been omitted and filed separately
with the commission. Confidential treatment has been requested with respect to
the omitted portions.