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                                                                   Exhibit 10.15

                                                            *** Text Omitted and
                                                                Filed Separately
                                                Confidential Treatment Requested
                                            Under 17 C.F.R. (S)(S) 200.80(b)(4),
                                                              200.83 and 230.406

                        Service Implementation Agreement
                                     Between
                          Akamai Inc. and SkyCache Inc.
                                       For
                       The Distribution of Akamai Content

Whereas SkyCache is building a satellite based Global Broadcast Overlay Network
(GBON) for the Internet that facilitates the distribution of content and audio
video streams to servers located on the edge of the Internet and Akamai provides
servers which host such content utilizing their unique FreeFlow Server
architecture and software, and both parties agree that delivery of Akamai
originated content via SkyCaches GBON offers financial and performance
advantages to Akamai, the parties agree as follows:

1.0  Service Definition Effort
     -------------------------

SkyCache will provide to Akamai a SkyCache receive satellite capability at its
location in Cambridge Massachusetts, and Akamai will locate a Free Flow Server
at SkyCaches facility in Laurel MD.  The purpose of this effort will be to
determine the specific method and manner for the acceptance of content from
Akamai and delivery of same over the SkyCache GBON to be received by the
SkyCache dish at Akamai's location in Cambridge Mass.  Both organizations agree
to commit the engineering resources essential to the completion of this effort
by November 30, 1999 and to develop the specific service agreement for
implementing the SkyCache Service into the Akamai infrastructure.  Both Parties
agree to bear their own costs in conducting this effort.

2.0  Co-Location of SkyCache GBON and Akamai Free Flow Server
     --------------------------------------------------------

SkyCache and Akamai each have equipment at ISP's and colocation facilities
throughout the Internet.  In order to facilitate delivery of Akamai content to
the existing Free Flow Servers, SkyCache will use its best efforts to place its
receive only dishes and related equipment at each of the existing Akamai Free
Flow Server Locations.  Costs associated with this deployment and any ongoing
monthly costs, if any, will be borne by SkyCache.  Akamai will provide support
by assisting SkyCache in this effort through requesting the "host" of each Free
Flow Server to accommodate this installation as Akamai intends to use the
SkyCache dish as a vehicle for the distribution of content to its FreeFlow
Servers.  Connection of the free flow servers to the SkyCache equipment (i.e.
cross connect charges, cabling charges, etc) will be the responsibility of
Akamai.

SkyCache has its equipment located at a number of ISP's and colocation
facilities where Akamai currently does not have a FreeFlow Server located.
SkyCache will use its best efforts to secure rack space at each of its ISP
locations for placement of Akamai FreeFlow Servers.  Costs, if any, for the
space required to locate the server at a SkyCache location will be borne by
Akamai.

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On all future deployments of facilities and equipment, both parties will make
mutual best efforts to include as part of their deployment plan the location of
each other's equipment at the new location.  The election to place the equipment
at a particular location will, however, be at the option of each party.  Costs
unique to the parties will be borne by the owner of the equipment.

Within thirty days (30) following the execution of this Agreement, SkyCache and
Akamai will have developed a detailed plan for the execution of the above
implementation.  Following completion of the efforts discussed in this
Agreement, both parties agree to assign the resources appropriate to execution
of this deployment.

3.0  SkyCache Global Broadcast Capacity
     ----------------------------------

Akamai wishes to purchase and SkyCache agrees to provide capacity for the
delivery of Akamai content on SkyCache's GBON for coverage within the North
American and European footprint.  (See Attachment A.)  SkyCache will make this
capacity available on a schedule to be developed which will provide ability for
Akamai to ramp up its utilization of this capacity over a six-month period from
the initiation of service which will be targeted to begin January 1, 2000.  The
cost for this capacity is as defined in Attachment B to this Agreement.

The implementation plan will include but not be limited to specifying the
locations at which Akamai wishes to have, and SkyCache has or can install
facilities to provide delivery of Akamai content to its FreeFlow servers.  The
method and manner in which Akamai content will be made available to SkyCache for
uplinking from the SkyCache uplink in Laurel MD and the Interface between
SkyCache and Akamai for the verification of compliance with the service level
criteria will be developed and agreed to by both organizations.

4.0  General Intellectual Property
     -----------------------------

This Agreement grants no rights of ownership of license of either Party's
software to the other Party.  Each party will retain sole title to any hardware,
software or documentation utilized in connection with these services.  Any
publicity or use of either Party's name in advertising shall be upon mutual
Agreement.

5.0  Dispute Resolution
     ------------------

     5.1  Informal Dispute Resolution.  In the case of any disputes under this
Agreement, the parties shall first attempt in good faith to resolve their
dispute informally, or by means of commercial mediation, without the necessity
of a formal proceeding.

     5.2 Arbitration of Disputes.

         5.2.1 Any controversy or dispute arising out of or relating to this
Agreement, or the breach thereof, which cannot otherwise be resolved as provided
above shall be resolved by arbitration conducted in accordance with the
commercial arbitration rules of the American Arbitration Association ("AAA") and
judgment upon the award rendered by the arbitral tribunal may be entered in any
court having jurisdiction thereof. The arbitration tribunal shall consist of a
single arbitrator mutually agreed by the parties, or in the absence of such
agreement within thirty (30) calendar days from the first referral of the
dispute to the AAA, designated by the

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AAA. The place of arbitration shall be Boston, Massachusetts, U.S.A., unless the
parties shall have agreed to another location within fifteen (15) calendar days
from the first referral of the dispute to the AAA, designated by the AAA. The
place of arbitration shall be Boston, Massachusetts, U.S.A., unless the parties
shall have agreed to another location within fifteen (15) calendar days from the
first referral of the dispute to the AAA. The arbitral award shall be final and
binding. The parties waive any right to appeal the arbitral award, to the extent
a right to appeal may be lawfully waived. Each party retains the right to seek
judicial assistance: (i) to compel arbitration; (ii) to obtain interim measures
of protection prior to or pending arbitration, (iii) to seek injunctive relief
in the courts of any jurisdiction as may be necessary and appropriate to protect
the unauthorized disclosure of its proprietary or confidential information, and
(iv) to enforce any decision of the arbitrator, including the final award.

         5.2.2 The arbitration proceedings contemplated by this Section 5 shall
be as confidential and private as permitted by law. To that end, the parties
shall not disclose the existence, content or results of any proceedings
conducted in accordance with this Section 5, and materials submitted in
connection with such proceedings shall not be admissible in any other
proceeding, provided, however, that this confidentiality provision shall not
prevent a petition to vacate or enforce an arbitral award, and shall not bar
disclosures required by law.

6.0  Indemnification and Liability.  In no event shall either party be liable to
     -----------------------------
the other for consequential or indirect losses or damages howsoever arising
under this Agreement and whether under contract, tort or otherwise (including
without limitation, third party claims, loss of profits, loss of customers, or
damage to reputation or goodwill).  Akamai shall indemnify, defend and hold
Carrier harmless from any and all claims, actions, losses, damages, costs and
expenses suffered by Carrier as a result of or directly related to any content
that is altered while on the Akamai servers.  The Carrier shall indemnify,
defend and hold Akamai harmless from any and all claims, actions, losses,
damages, costs and expenses suffered by Akamai as a result of or related to
Carrier's negligence or intentional misconduct, status as a telecommunications
provider, Carrier communication services or the Network.

     THE PROVISIONS OF THIS SECTION 6 STATE THE SOLE AND EXCLUSIVE OBLIGATIONS
AND LIMITATION OF LIABILITY OF EITHER PARTY FOR ANY PATENT, COPYRIGHT,
TRADEMARK, TRADE SECRET OR OTHER INTELLECTUAL PROPERTY RIGHTS INFRINGEMENT AND
ARE IN LIEU OF ANY WARRANTIES OF NON-INFRINGEMENT, ALL OF WHICH ARE DISCLAIMED.

     IN NO EVENT SHALL EITHER PARTY BE LIABLE TO THE OTHER FOR ANY INCIDENTAL,
CONSEQUENTIAL, OR ANY OTHER INDIRECT LOSS OR DAMAGE, INCLUDING LOST PROFITS,
ARISING OUT OF THIS AGREEMENT OR ANY OBLIGATION RESULTING THEREFROM, REGARDLESS
OF THE FORM OF ACTION, WHETHER IN CONTRACT, TORT (INCLUDING NEGLIGENCE), STRICT
LIABILITY OR OTHERWISE.

7.0  WARRANTY DISCLAIMER.  NEITHER PARTY MAKES ANY REPRESENTATIONS OR
     -------------------
WARRANTIES, EITHER EXPRESS OR IMPLIED, AND AKAMAI SPECIFICALLY DISCLAIMS ANY
IMPLIED WARRANTIES OF

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MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE WITH RESPECT TO THE AKAMAI
SERVICES.

8.0  Miscellaneous.
     -------------

     8.1 Independent Contractor. The relationship of Akamai and Carrier
established by this Agreement is that of Independent contractors, and nothing
contained in this Agreement shall be construed to (i) give either party the
power to direct and control the day-to-day activities of the other, (ii) deem
the parties to be acting as Carriers, joint venturers, co-owners or otherwise as
participants in a joint undertaking; or (iii) allow either party to create or
assume any obligation on behalf of the other party for any purpose whatsoever.

     8.2 Notices. Any notice required or permitted hereunder shall be in writing
and will be deemed given when delivery by hand or deposited in the mails or with
common carriers. All communications will be sent by mail, facsimile or
electronic mail to the receiving party's contact person for notices listed on
the cover page of this Agreement.

     8.3 Assignment. Either party may not, without the prior written consent of
the other Party, such consent not being unreasonably withheld, assign this
Agreement, in whole or in part, either voluntarily or by operation of law, and
any attempt to do so shall be a material default of this Agreement and shall be
void.

     8.4 Third Party Beneficiaries. This Agreement is solely for the benefit of
the parties and their successors and permitted assigns, and does not confer any
rights or remedies on any other person or entity.

     8.5 Governing Law. This Agreement shall be interpreted according to the
laws of the Commonwealth of Massachusetts without regard to or application of
choice-of-law rules or principles.

     8.6 Entire Agreement and Waiver. This Agreement and the Confidential
Disclosure Agreement executed by the parties constitute the entire agreement
between Akamai and Carrier with respect to the subject matter hereof and all
other prior agreements, representations, and statement with respect to such
subject matter are superceded hereby.

     8.7 Severability. In the event any provision of this Agreement is held by a
court of competent jurisdiction to be unenforceable, that provision will be
enforced to the maximum extent permissible under applicable law, and the other
provisions of this Agreement will remain in full force and effect.

     8.8 Force Majeure. If either party is prevented from performing any of its
obligations under this Agreement due to any cause beyond the party's reasonable
control, including, without limitation, an act of God, fire, flood, explosion,
war, strike, embargo, government regulation, civil or military authority, (a
"force majeure event") the time for that party's performance will be extended
for the period for the delay or inability to perform due to such occurrence;
provided, however, that if a party suffering a force majeure event is unable to
cure that event within thirty (30) days, the other party may terminate this
agreement immediately.

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     8.9  Counterparts. This Agreement may be executed in any number of
counterparts, each of which, when so executed and delivered, shall be deemed an
original, and all of which shall constitute one and the same Agreement.

     8.10 Binding Effect. This Agreement shall be binding upon and shall inure
to the benefit of the respective parties hereto, their respective successors-in-
interest, legal representatives, heirs and assigns.

     8.11 Compliance with Laws. Each party agrees to comply with all applicable
laws, regulations, and ordinances relating to their performance hereunder.

     8.12 Survival of Obligations. Sections 4, 5, 6, 7, and 8 shall survive any
termination, cancellation or expiration of this Agreement for any reason.


     Executed and Agreed by:


     /s/ Robert E. Marggraf           /s/ Jonathan Seelig
     -------------------------        -------------------
     Robert E. Marggraf               Jonathan Seelig
     Executive Vice President         Vice President
     SkyCache Inc.                    Strategy & Corporate Development
     312 Laurel Avenue                AKAMAI Technologies
     Laurel, MD  20707                201 Broadway
                                      Cambridge, MA  02139

     ATTACHMENTS

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<PAGE>

                                  Attachment A
                        SkyCache Service Coverage Areas



1.0  North America:
     SkyCache provides the ability to deliver content via its GBON throughout
     the continental United States, and Hawaii by placing 1.2 Meter Satellite
     dishes and receiver equipment at locations that will facilitate the
     delivery of customer content. SkyCache has an agreement with TeleSat Canada
     for distribution within the provinces of Canada. The placement of the
     satellite dish will be by SkyCache following a site survey to assure line
     of sight to the satellite being utilized by SkyCache.

2.0  Europe:
     SkyCache provides the ability to delivery content via its GBON in Europe to
     the Pan-European and Nordic Countries by placing .9 Meter Satellite dishes
     and receiver equipment at locations which will facilitate the delivery of
     customer content. The placement of the satellite dish will be by SkyCache
     following a site survey to assure line of sight to the satellite being used
     by SkyCache.

3.0  Asia and Latin America:
     SkyCache is currently finalizing negotiations to provide similar services
     to these areas and anticipates availability within the 1st half of the Year
     2000.

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                             Attachment B - Pricing

     It is our understanding that Akamai intends to use SkyCache for the
     distribution of live audio video streams as well as files which contain
     software updates to Akamai Free Flow Servers located throughout the
     Internet.

     Outlined below is the pricing for the delivery of audio video streams. Once
     SkyCache has a better understanding of the specific requirements associated
     with the delivery of software updates (file sizes, window for delivery,
     time of day, frequency of transmission, etc) which will be developed under
     the effort described in Paragraph 1 of this Agreement, pricing will be
     provided for this service as well. SkyCache anticipates, based on similar
     efforts and prices, that this service will result in significant benefits
     to Akamai for both software distribution and management. [ *** ]

     Price Quote for the Transport of Akamai Data in each Coverage Area.

     [   ***   ]



*** Confidential Treatment Requested


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