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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 Technologies, Inc. and Cidera Inc.

     This Service Implementation Agreement ("Agreement") is entered into as of
May 22, 2000, (the "Effective Date") by and between Cidera, Inc., a Delaware
corporation having its principal place of business at 3087 Laurel Lakes Drive,
Laurel, MD 20707 ("Cidera"), and Akamai Technologies, Inc., a Delaware
corporation having its principal place of business at 500 Technology Square,
Cambridge, MA 02139 ("AKAMAI"). Cidera and AKAMAI are referred to herein
collectively as the "Parties" and individually as a "Party".

                                    PREAMBLE

     Whereas, Cidera is in the process of building a satellite based Global
Broadcast Overlay Network (GBON) for the Internet that facilitates the
distribution of Media to servers located on the edge of the Internet.

     Whereas, Akamai provides Internet content and streaming media delivery
services and applications delivery and execution though a worldwide server
network (the "Akamai Services") and Cidera intends to distribute streaming media
over the GBON (the "Cidera Service").  Both Parties agree that delivery of
AKAMAI customer's content via Cidera's GBON may potentially offer financial and
performance advantages to AKAMAI.

     Now, Therefore, in consideration of the mutual promises and covenants set
forth herein, and for other good and valuable consideration, the receipt and
sufficiency of which are hereby acknowledged, the Parties hereto agree as
follows:

                                   AGREEMENT

1.  Definitions:

    The following capitalized terms shall have the meanings as set forth below:

    1.1  "Akamai Services" has the meaning set for the in the Preamble.
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    1.2  "Audio/Video Service Provider" means a company, or a division of a
company, that provides Internet audio and/or video hosting, and/or management
services to Clients.

    1.3  "Client" means a Media owner, licensor, producer, aggregator, and/or
syndicator whether acting directly or through an agency.

    1.4  "Co-Location Facility" means a facility which provides co-location to
the general public and which has at least 5,000 square feet of net machine co-
location space.

    1.5  "Media" means content containing live, simulated live, on-demand, or
downloadable audio and/or video using any major video compression formats such
as Microsoft Windows Media, RealNetworks RealMedia, Apple Quicktime, MPEG, and
streaming Java.

    1.6  "Locations" means current or future facilities at which Cidera makes
available its receive-only satellite capability and to which AKAMAI connects to
receive Media delivered by Cidera to AKAMAI equipment.

    1.7  "Non-Enterprise Network" means a network that resells bandwidth as part
of its normal course of business, including without limitation, ISPs, cable head
ends, DSL nodes and college or university networks.

    1.8  "Committed Capacity" means the amount of broadcast bandwidth in Mbps.
increments for AKAMAI's sole use on a 7 day, 24 hour basis.

    1.9  "String of Equipment" means a satellite antenna, receiver, router,
ethernet switch and any required cabling, the makeup of which may change over
time provided that the level of service agreed to in the SLA remains consistent.

2.  SERVICE DEFINITION AND OVERVIEW

    Cidera agrees to provide to AKAMAI (i) receive-only satellite downlinks
capable of receiving one-way, multicasted Internet protocol Media, at one or
many Locations, as designated from time to time by AKAMAI, including Locations
in service areas outside of the continental United States (see Attachment A -
Service Coverage Areas) and (ii) satellite transport to such Location(s), in
accordance with the terms of this Agreement.  Cidera agrees to provide such
service ("Cidera Service") at the 38 Locations described in Section 2.1 at
[ * * * ], and AKAMAI agrees to deploy appropriate AKAMAI equipment at Cidera's
current and planned uplink facilities, including, without limitation, its
facility in Laurel, MD, to the extent that such deployment is mutually
determined by the Parties to be necessary in order for AKAMAI to use the Cidera
Service.  Implementation of the Cidera Service shall consist of four steps:  (i)
a proof of concept (see Attachment D:  "Proof of Concept"); (ii) a mutually
agreed upon service acceptance checklist ("Service Acceptance Checklist"); (iii)
a mutually agreed upon Service Level Agreement ("SLA"); and, (iv) implementation
of the Cidera Service.


*** Confidential Treatment Requested
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          (a)  Proof of Concept.  Both parties agree to commence testing of the
Cidera Service within [ * * * ] of the Effective Date by means of a mutually
agreed upon Proof of Concept, the schedule and requirements of which the
guidelines are listed in Attachment D.  Testing by means of the Proof of Concept
shall be completed within [ * * * ] after the Effective Date, or at such later
time as the Parties mutually agree in writing.

          (b)  Service Acceptance Checklist.  Within thirty (30) days of
completion of the Proof of Concept the Parties shall mutually agree upon
criteria for the acceptance of the Cidera Service at Locations.  If the Parties
do not mutually agree upon such criteria within the thirty-day period, the
Parties may mutually agree in writing to extend the time period of Proof of
Concept.

          (c)  Service Level Agreement.  Also within thirty (30) days of the
completion of the Proof of Concept both parties shall mutually agree to develop
the  appropriate language for the network  SLA applicable to Akamai.  This SLA
shall, at a minimum, include the following guidelines:
1) [ * * * ] availability for uplink/hub/satellite;
2) [ * * * ] availability minimum for receive sites;
3) [ * * * ] overall network availability;
4) [ * * * ] packet delivery over 24-hrs at all remote sites in a given
continental footprint;
5) Less than [ * * * ] packet loss at the uplink, assuming IP multicast
streaming, and no use of higher-level applications, such loss measured at uplink
and not averaged over downlinks, and assuming use including bursting of less
than [ * * * ] of Akamai's CIR in a given region;
6) Penalty - [ * * * ];
7) A minor system-wide outage is one in which a single continental region is
generally unavailable ([ * * * ]) for less than [ * * * ];
8) A major system-wide outage is one in which a single continental region is
generally unavailable ([ * * * ]) for more than [ * * * ];
9) For each minor system-wide outage, Akamai receives [ * * * ];
10) For each major system-wide outage, Akamai received [ * * * ], and if there
are more than [ * * * ] major system-wide outages separated by more than
[ * * * ], Akamai receives credit for [ * * * ];
11) Availability excludes [ * * * ], of routine maintenance, which maintenance
shall  be rarely used, and said maintenance to occur on Tuesday night/Wed
morning, unless 72 hours of notice is provided;
12) Availability also excludes [ * * * ], of emergency maintenance, however more
than [ * * * ] of cumulative outage shall cause a penalty of [ * * * ].

    2.1  Initial Deployment.  Following completion of the Proof of Concept, both
parties shall mutually agree upon the Service Acceptance Checklist and a Service
Level Agreement as set forth above in this Section 2.  At such time, Cidera will
install the Cidera Service at a minimum of thirty-eight (38) Locations. (see
Attachment A - Service Coverage Areas).  Cidera shall perform such
installations, provided that there are no unreasonable constraints imposed on
Cidera by building management or local zoning laws. AKAMAI agrees to provide
Cidera with


*** Confidential Treatment Requested
<PAGE>

the current contacts for the Locations to facilitate the installation of Cidera
equipment.  See Attachment E for Location installation and configuration
specifications and the division of cost between Parties.  Cidera and AKAMAI will
each provide engineering resources to facilitate any software interfaces between
the two networks.

    2.2  Other Deployments.  As Cidera continues to deploy its GBON, AKAMAI may
elect to locate its equipment at existing Cidera Locations or AKAMAI may request
that Cidera place its equipment at new facilities where AKAMAI locates its
equipment.  Both Parties agree to use commercially reasonable efforts to
facilitate the location of each other's equipment at these locations at no cost;
provided, however the election to place a Party's equipment at a particular
location will be at the option of such Party in its sole discretion.  If costs
are applicable, then each Party will bear the costs as referenced in Attachment
E. [ * * * ].

    2.3  [ * * * ].

    2.4  Deployment of New Applications and Services. Throughout the Term,
Cidera will make available to AKAMAI all new applications and services related
to those described in Section 2 herein concurrently with or sooner than the
availability schedule for such new services or products generally provided to
other Cidera customers.

    2.5  On-Site Monitoring. Cidera agrees to use commercially reasonable
efforts to make available to AKAMAI certain software which will facilitate the
on-site monitoring of the delivery of AKAMAI content via the GBON. The terms of
any such license shall be mutually agreed upon by the parties and set forth
under separate agreement.

    2.6  Dedicated Locations.  Cidera will provide Akamai, if requested, with a
String of Equipment dedicated for Akamai Services at locations where [ * * * ]
(collectively, "Dedicated Locations").  A site shall not be deemed a Dedicated
Location, if: [ * * * ].  At sites that qualify as Dedicated Locations, Cidera
will provide Akamai with a standard String of Equipment dedicated to Akamai
Services. Notwithstanding the foregoing, Cidera reserves the right to offer
Cidera Commercial Services over the Akamai dedicated equipment string at the
Dedicated Locations. As used herein, "Cidera Commercial Services" means  (i)
services offered by Cidera to Non-Enterprise Networks as of the Effective Date
or during the Term, whether for a charge or free-of-charge, provided that such
services are not streaming media or content delivery services, or execution of
applications for third party customers, or (ii) UseNet News,  Cache
Turbocharging, and Big File Mover (as they exist on the Effective Date or during
the Term provided that the service offerings do not substantially change from
the Effective Date).  Beginning on the date which is two and one-half years
after the Effective Date, Akamai shall no longer have the option to designate
locations as Dedicated Locations.

    2.7  VAST at Dedicated Locations. Cidera shall have the option to install
VAST (Virtual Application Server Technology) at the Dedicated Locations at its
own initial and recurring cost, but in the event of such an installation, shall
only use the VAST in connection with the provision of either Cidera Commercial
Services or Akamai Services (subject to the exception set forth in Section
2.11).


*** Confidential Treatment Requested
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    2.8  Dedicated Location Fees. At Dedicated Locations, AKAMAI agrees to pay a
dedicated site fee of [ * * * ] for the dedicated equipment referenced in
Section 2.6 in addition to the standard 7X24 streaming charges set forth in
Attachment B.
------------

    2.9  Confidentiality of Dedicated Location and Related Information.  Cidera
agrees to develop and implement reasonable and adequate measures to protect the
confidentiality of the list of those sites which are deemed Dedicated Locations
with the intention to limit the dissemination and/or disclosure of such
information to Akamai personnel and / or the Cidera Akamai Implementation team
only.  It is Cidera's intention to locate the core of the Cidera team dedicated
to Akamai in Boston during deployment of the Services.  Consistent with the
foregoing, Cidera will develop and maintain a list of Dedicated Locations (the
"Akamai Dedicated Location List"), and will segregate this information from
other Cidera customers or potential customers.  The Akamai Dedicated Location
List will also be segregated from general external and internal Cidera
distribution. Cidera shall not release the Akamai Dedicated Location List or
otherwise identify a Dedicated Location  to existing or prospective Cidera
customers. In addition, Cidera shall not disclose any information relating to
Dedicated Locations to any other Dedicated Location (including, without
limitation, to its employees, agents or representatives). In addition, Cidera
shall not disclose any information relating to any existing or prospective
Cidera customer (including, without limitation information regarding such
existing or prospective customer's services) to any Dedication Location
(including, without limitation, to its employees, agents or representatives).
Within 20 days of the Effective Date (or by such later date as the Parties
mutually agree in writing), Akamai and Cidera will mutually develop the specific
procedures and details for effectively segregating information relating to
Dedicated Locations, the process for managing such information, and the
guidelines for determining whether a breach of Cidera's obligations has
occurred; provided that, failure by the Parties to agree upon such guidelines
during the 20 day period shall not relieve Cidera of its obligations under this
Section 2.9.

    2.10  Additional Equipment at Dedicated Locations. Cidera shall have the
right to install a second String of Equipment if requested by a customer
pursuant to a bona fide purchase order for network services on a Cidera Site
Services Activation Form (P.O.).

    2.11  Movement of a Dedicated Location to a Public Site. Cidera will move
each Dedicated Location to the Cidera Public Site Catalog at any point in time
that [ * * * ]. Once a Location is in the Cidera Public Site Catalog, the VAST
at such Location will no longer be subject to the usage restrictions set forth
in Section 2.7.

    2.12  Unauthorized Disclosure of Dedicated Locations Information. In the
event that Cidera breaches its obligations set forth in Section 2.9 resulting in
information regarding Dedicated Locations being disclosed (each such occurrence,
a "Violation"), then the following procedures will be implemented. Should there
be more than [ * * * ] Violations in a [ * * * ] period, then the parties will
use good faith efforts to agree on procedures to prevent additional Violations,
and Cidera will have [ * * * ] to implement such procedures. If Cidera fails to
implement such procedures within the [ * * * ] period, and Akamai does not
terminate this Agreement pursuant to Section 4.2(a), then Cidera shall provide
Akamai with [ * * * ].

*** Confidential Treatment Requested
<PAGE>

     In the event that there are more than [ * * * ] Violations in any [ * * * ]
period, or if there is a breach in more than [ * * * ] of the Dedicated
Locations, whichever is greater at the time,  then the parties will agree on
procedures to prevent additional Violations, and Cidera will have [ * * * ] to
implement such procedures.  If Cidera fails to implement such procedures within
the [ * * * ] period, or if within [ * * * ] after such [ * * * ] period either
(i) the procedures are not working for their intended purpose in a manner
reasonably satisfactory to Akamai, or (ii) the breach has been repeated, then
from that point forward, all Locations that are Dedicated Locations at such time
and any additional Akamai sites that qualify to become Dedicated Locations
pursuant to this Agreement shall remain Dedicated Locations until an acceptable
procedure to prevent future Violations is agreed upon and the network remains
without a violation for a period of [ * * * ], at which time the Parties will
meet and  remove the restriction on Dedicated Locations.

    2.13  Services Pricing.  AKAMAI agrees to pay Cidera for the Services in
accordance with the 7x24 Services Pricing set forth in Attachment B. Service to
a Cidera Public Location shall require a minimum service commitment of 12
months. Service to Dedicated Location shall require a minimum service commitment
of 24 months.

    2.14  Network Commitment. Akamai agrees to initiate delivery of Akamai
Services utilizing the GBON to a minimum 350 Locations by 12/31/00; and 750
locations by 6/30/01; provided that Cidera has made at least [ * * * ] Locations
available in the Cidera Public Site Catolog by 6/30/01. Akamai agrees to
initiate delivery of Akamai Services utilizing the GBON to 1,500 total Locations
by 12/31/01, provided that Cidera has made [ * * * ] Locations available in the
Cidera Public Site Catalog by 12/31/01. For the purposes of the preceding
sentence, a site will be deemed "made available" in the Cidera Public Site
Catalog if a purchase order for services has been provided to and accepted by
Cidera with installation scheduled to occur within 30 days of the purchase order
date. Should these commitment levels not be met at the dates listed above,
Akamai agrees to pay the minimum charge for Services based upon the target
number of Locations at the then current bandwidth consumption levels as set
forth in Attachment B from that point forward until those minimum installations
are achieved. For example, if at 12/31/00 usage is at 5 Mbps and there are fewer
than 350 Locations, then beginning 1/01/01 the pricing will be for 350 Locations
at 5 Mbps.

    2.15  Ramp-Up Period. [ * * * ].

    2.16  Event Based Services. AKAMAI may also purchase event-based services
from Cidera. A matrix of pricing is contained in Attachment C.

    2.17  Pricing Confidentiality.  The prices contained in this Agreement are
considered confidential and disclosure of this information shall be treated
consistently with the Non-Disclosure Agreement executed between the Parties.

    2.18  [ * * * ].

*** Confidential Treatment Requested
<PAGE>

    2.19  The pricing shown in Attachment B is contingent upon delivery by
AKAMAI of encoded streams to the Cidera uplink facility in Laurel, MD. As a
component of the Initial Deployment (Section 2.1) Cidera and AKAMAI will
determine and mutually agree upon the method and delivery of the AKAMAI Media to
current and future Cidera uplink facilities or Content Receipt Points. Cidera
agrees that Akamai shall be permitted to deliver Akamai Media to the AboveNet
facility in Virginia for transfer to the Cidera uplink at such facility "Content
Receipt Points" means points withn the Cidera Network that Cidera places in
publicly general available Co-location Facilities for its customers to access
the Cidera uplinks. Akamai shall have the same access to Content Receipt Points
as Cidera provides to its other similarly situated customers.

    2.20  Other Charges. AKAMAI may elect to receive the Cidera Service at a new
Location at its option. If AKAMAI requests a Location where Cidera does not
desire to locate its service and equipment [ * * * ].

3.  Channel Conflict Arrangement

    During the Term, Cidera agrees to not directly provide audio/video
streaming content or streaming media application software required for hosting
to End Users.  The foregoing restriction shall not apply to Cidera's provision
of Cidera services for transport, server hardware and related infrastructure.
For the purposes of the first sentence of this Section, the term "END USER"
means a subscriber to the Internet who receives audio/video content directly
from the Internet.  In the event that Cidera breaches the foregoing covenant,
AKAMAI's sole remedy shall be as set forth in Section 4.2 and 6.

4.  Term And Termination

    4.1  Term. The term of this Agreement will commence on the Effective Date
and continue for a term of 48 months (the "Initial Term"). In the second, third
and fourth years of this Agreement, the prices set forth in Attachments B and C
shall [ * * * ].

    4.2  Termination. A Party may terminate this Agreement, upon written notice
to the other Party: (a) for any material breach of this Agreement, which the
defaulting Party fails to cure within thirty (30) days following written notice
of such breach; or (b) upon the other Party's insolvency or liquidation. AKAMAI
may terminate this Agreement for convenience upon fifteen (15) days' prior
written notice to Cidera and pre-payment in full of a Termination Charge (as
defined below). For the purposes of the preceding sentence, the term,
"Termination Charge" shall mean [ * * * ]. The Parties agree that in the event
of early termination by AKAMAI for convenience as provided for above, the
Termination Charge is a fair and reasonable fee for services rendered and
Cidera's cost incurred and is not to be construed as a penalty.

    4.3  Effect of Termination.  Sections 5, 6, 7, 8, and 9 shall survive any
termination or expiration of this Agreement for any reason.



*** Confidential Treatment Requested
<PAGE>

5.  Intellectual Property Rights

    5.1  Retention of Ownership. Except as expressly provided in this Agreement,
each Party retains ownership of its intellectual property and does not license
any of its intellectual property to the other Party.

    5.2  No Implied License.  Except as expressly set forth in this Agreement,
neither Party grants to the other Party, either directly or by implication, by
estoppel or otherwise, any rights or licenses.

    5.3  No Other Rights.  Notwithstanding anything in this Agreement to the
contrary, the rights granted in this Agreement do not include any right,
license, release or immunity, directly or indirectly, express, implied or by
estoppel, in or to any of either Party's process technology or other technology
under any patent, copyrights, trade secret, mask work or other intellectual
property right.  Except as expressly set forth in this Agreement, neither Party
shall modify, adapt, translate, prepare derivative works from, decompile,
reverse engineer, disassemble or otherwise attempt to derive source code from
software provided by one Party to the other or from any internal data files
generated by such software.

6.  Indemnification And Liability

     EACH PARTY (THE "INDEMNIFYING PARTY") HEREBY AGREES TO INDEMNIFY AND HOLD
HARMLESS THE OTHER PARTY (THE "INDEMNIFIED PARTY") AND THE INDEMNIFIED PARTY'S
PARENT, SUBSIDIARIES AND AFFILIATES, AND THE DIRECTORS, OFFICERS, EMPLOYEES,
AGENTS AND REPRESENTATIVES OF SUCH PARTY AND THOSE OF ITS AFFILIATES, FROM AND
AGAINST THE FULL AMOUNT OF ANY AND ALL THIRD PARTY CLAIMS, ACTIONS,
COUNTERCLAIMS, LAWSUITS, DAMAGES, LOSSES, JUDGMENTS AND EXPENSES, INCLUDING,
WITHOUT LIMITATION, REASONABLE ATTORNEYS' FEES AND EXPENSES, REASONABLE OUT-OF-
POCKET EXPENSES AND COURT COSTS, THAT SUCH PARTY AND/OR ANY OF THE FOREGOING
ENTITIES OR INDIVIDUALS MAY INCUR AS A RESULT OF OR OTHERWISE RELATED TO (i) ANY
MATERIAL BREACH BY INDEMNIFYING PARTY OF ANY OBLIGATION HEREUNDER, OR ACT OR
OMISSION OF PERFORMANCE BY THE INDEMNIFYING PARTY CONSTITUTING A MATERIAL BREACH
HEREUNDER, OR (ii) ANY CLAIM OF INFRINGEMENT OR MISAPPROPRIATION OF ANY
INTELLECTUAL PROPERTY OR PROPRIETARY RIGHTS OF ANY THIRD PARTY, INCLUDING
WITHOUT LIMITATION, COPYRIGHTS OR TRADEMARKS BASED UPON THE PROVISION OF
SERVICES AND/OR CONTENT BY THE INDEMNIFYING PARTY PROVIDED, HOWEVER, THAT THE
INDEMNIFIED PARTY MUST (i) GIVE TO THE INDEMNIFIED PARTY PROMPT WRITTEN NOTICE
OF ANY CLAIM, ACTION OR OTHER MATTER TO WHICH THIS INDEMNIFICATION APPLIES; (ii)
AFFORD TO THE INDEMNIFYING PARTY THE OPPORTUNITY TO PARTICIPATE IN AND CONTROL
(WITH LEGAL COUNSEL OF ITS CHOICE, PROVIDED SUCH LEGAL COUNSEL IS REASONABLY
ACCEPTABLE TO THE INDEMNIFIED PARTY), THE DISPOSITION (WHETHER BY COMPROMISE,
SETTLEMENT OR OTHER RESOLUTION) OF SUCH CLAIM, ACTION, SUIT OR OTHER MATTER,
PROVIDED THAT THE INDEMNIFYING PARTY ACKNOWLEDGES ITS
<PAGE>

INDEMNIFICATION OBLIGATIONS; AND (iii) FULLY COOPERATE WITH THE REASONABLE
REQUESTS OF THE INDEMNIFYING PARTY TO THAT END.

     EXCEPT FOR EACH PARTY'S INDEMNIFICATION OBLIGATIONS FOR INFRINGEMENT OF
THIRD PARTY INTELLECTUAL PROPERTY RIGHTS AND BREACH OF SECTIONS 5 AND 8, IN NO
EVENT SHALL EITHER PARTY BE LIABLE TO THE OTHER FOR INCIDENTAL, SPECIAL,
CONSEQUENTIAL, OR ANY OTHER INDIRECT LOSS OR DAMAGE, INCLUDING, WITHOUT
LIMITATION, LOST PROFITS, ARISING OUT OF THIS AGREEMENT OR ANY OBLIGATION
RESULTING THEREFROM, REGARDLESS OF THE FORM OF ACTION, WHETHER IN CONTRACT, TORT
(INCLUDING, WITHOUT LIMITATION, NEGLIGENCE), STRICT LIABILITY OR OTHERWISE.

     EXCEPT FOR EACH PARTY'S INDEMNIFICATION OBLIGATIONS FOR INFRINGEMENT OF
THIRD PARTY INTELLECTUAL PROPERTY RIGHTS AND BREACHES OF SECTIONS 5 AND 8, IN NO
EVENT SHALL THE AGGREGATE LIABILITY OF EITHER PARTY UNDER THIS AGREEMENT EXCEED
[ * * * ].

7.  Warranty Disclaimer

    EXCEPT AS EXPRESSLY PROVIDED HEREIN, NEITHER PARTY MAKES ANY
REPRESENTATIONS OR WARRANTIES, EITHER EXPRESS OR IMPLIED, AND BOTH PARTIES
SPECIFICALLY DISCLAIM ANY IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
A PARTICULAR PURPOSE WITH RESPECT TO THEIR RESPECTIVE SERVICES.

8.  Confidential Information

     Except as and to the extent required by law, neither Party will disclose or
use (other than for purposes of the definitive Agreement), and will direct its
representatives not to disclose or use (other than for purposes of the
definitive Agreement), to the detriment of the other Party, any Confidential
Information (as defined below) with respect to the business or the other Party
furnished, or to be furnished, by such Party, or their respective representative
to the other Party or its representatives at any time or in any manner other
than disclosures to employees on a need-to-know basis. For purposes of this
Paragraph, "Confidential Information" means any information about the ongoing
negotiations related to this Agreement or the business or activities of either
Party stamped "confidential" or identified in writing as such by a Party to the
other Party promptly following its disclosure.  Disclosure of Confidential
Information to employees and agents of the parties hereto will be limited to a
need-to-know basis under circumstances where the employee or agent is advised of
the confidential nature of the disclosure and is bound to keep said information
confidential.  Notwithstanding the foregoing, the following information shall
not be deemed Confidential Information: (i) information that is already known to
the recipient Party or its representatives who are not bound by a duty of
confidentiality prior to disclosure, in each case without a breach of a legal
obligation; (ii) information that becomes publicly available through no fault of
the recipient Party or its representatives; (iii) information

*** Confidential Treatment Requested
<PAGE>

that is independently developed by a Party without the use of or reference to
the Confidential Information of the other Party; or (iv) information that
properly comes into the recipient's possession from a third Party who is not
under an obligation to maintain the confidentiality of such information.
Notwithstanding anything contained herein, it shall not be a breach of this
provision for either Party to disclose Confidential Information to comply with
any applicable subpoena or other legal or regulatory requirement, so long as the
recipient notifies the disclosing Party prior to making such disclosure and
takes reasonable and lawful actions to avoid and/or minimize the extent of such
disclosure.  Akamai hereby consents to the filing of this Agreement as an
exhibit to the Registration Statement of Cidera on Form S-1 in connection with
its initial public offering, if Cidera, in its reasonable discretion, determines
that SEC regulations require such filing.  Akamai understands that as of the
Effective Date, Cidera has made such determination to file this Agreement.  In
addition, Cidera agrees that it shall use best efforts, consistent with
commercial reasonableness, to obtain "confidential treatment" of any
Confidential Information of AKAMAI which it is required to include in its SEC
filings, including its Registration Statement on Form S-1 which is presently
pending.  The parties agree to cooperate in connection with any such
confidential treatment request (the "Request").  To this end, Cidera agrees to
provide Akamai with drafts of the Request (including proposed redactions to the
publicly filed version of this Agreement) and any amendments thereto, a
reasonable period of time prior to submission to the SEC, for input from Akamai.
Akamai recognizes that the Request is time-sensitive and, accordingly, agrees to
promptly provide its input with respect to the Request and any amendments
thereto.  Upon the written request of the disclosing Party, the recipient Party
will promptly return to the disclosing Party or destroy any Confidential
Information in its possession and certify in writing to the disclosing Party
that it has done so.


9.  Miscellaneous

    9.1  Independent Contractor. The relationship of AKAMAI and Cidera
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 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.

    9.2  Assignment. Neither Party may, without the prior written consent of the
other Party, which consent will not be unreasonably withheld, assign this
Agreement, in whole or in part, and any attempt to do so shall be a material
default of this Agreement and shall be void. Notwithstanding the foregoing, this
Agreement may be assigned by AKAMAI as allowed by operation of law or to any
affiliate so long as Akamai remains primarily liable for such affiliate's
performance hereunder.

    9.3  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.

    9.4  Dispute Resolution.
<PAGE>

         (a)  Equitable Relief. The Parties agree that any breach of any of the
Parties' obligations regarding intellectual property and/or confidentiality
would result in irreparable injury for which there is no adequate remedy at law.
Therefore, in the event of any breach or threatened breach of a Party's
obligations regarding intellectual property or confidentiality, the aggrieved
Party will be entitled to seek immediate equitable relief in addition to its
other available legal remedies in a court of competent jurisdiction.

         (b)  Escalation. In the event of disputes between the Parties arising
from or concerning in any manner the subject matter of this Agreement, other
than disputes set forth in subsection (a) above, the Parties will first attempt
to resolve the dispute(s) through good faith negotiation. Upon written notice by
a Party to the other that a dispute exists, the exact nature of the dispute
shall be identified, and good faith discussions and negotiations shall be
conducted within fifteen (15) days directly between senior management at AKAMAI
and Cidera (currently, Avi Freedman for AKAMAI and Robert Dunham for Cidera, or
their respective designees), with input from their respective technical and
business teams as they desire, to fully address the issues raised. Such meetings
shall be limited to one-half day unless otherwise agreed, scheduled at a
mutually convenient time, place and method. Each representative shall be
authorized to fully negotiate for, and bind, his or her respective company. If
such negotiations fail to adequately resolve the issues raised, the Parties
shall be free to resort to any applicable remedy at law, including such
mediation or other alternative dispute resolution mechanisms as they may agree
to. All discussions pursuant to this Section are agreed to be in the course of
pursuing settlement and shall be inadmissible in any subsequent litigation.

         (c)  Remedies. The remedies set forth in this Agreement are in addition
to those available to the Parties at law or in equity (subject to the
limitations of liability and other restrictions set forth herein), except as
specified regarding pre-litigation dispute resolution. All rights and remedies,
legal or equitable, whether conferred hereunder, or by any other instrument or
law will be cumulative and may be exercised singularly or concurrently.

         (d)  Governing Law. Any claim arising under or relating to this
Agreement shall be governed by the internal substantive laws of the State of
Delaware, without regard to principles of conflict of laws. Each Party hereby
agrees to non-exclusive jurisdiction in the courts of the State of Delaware for
all disputes and litigation arising under or relating to this Agreement.
Furthermore, the Parties agree that the terms of The U.N. Convention on
Contracts for the International Sale of Goods do not apply to this Agreement.

    9.5  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.

    9.6  Force Majeure. If either Party is prevented from performing any of its
obligations under this Agreement (excluding payment obligations) 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 of the delay or inability to perform
due to such occurrence; provided, however, that if a Party suffering a force
<PAGE>

majeure event is unable to cure that event within thirty (30) days, the other
Party may terminate this Agreement immediately.

    9.7   Counterparts. This Agreement may be executed in two (2) 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.

    9.8   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.

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

    9.10  Notices. All notices, consents, waivers, and other communications
under this Agreement must be in writing and will be deemed to have been duly
given when (a) delivered by hand (with written confirmation of receipt), (b)
sent by telecopier (with written confirmation of receipt), provided that a copy
is mailed by registered mail, return receipt requested, or (c) when received by
the addressee, if sent by a nationally recognized overnight delivery service
(receipt requested), in each case to the appropriate addresses and telecopier
number set forth below (or to such other addresses and telecopier numbers as a
Party may designate by notice to the other Parties):

     If to AKAMAI, to:

          Akamai Technologies, Inc.
          500 Technology Square,
          Cambridge, MA  02139
          Attn: Avi Freedman
          Phone: 617-250-3000
          Fax: 617-250-4770

     with a copy to:

          Robert Ball, Vice President and General Counsel

     If to Cidera, to:

          Cidera, Inc.
          8037 Laurel Lakes Court
          Laurel, MD  20707
          Attn: Dutch Dunham
          Phone: 301-598-0500, x2201
          Fax: 301-598-0837
<PAGE>

     with a copy to:

          Edward D. Postal, Chief Financial Officer

     9.11  Modifications. This Agreement may not be modified, amended, changed
or discharged, in whole or in part, except as specifically provided herein or by
an agreement in writing signed by a duly authorized representative of each of
the parties.

10.  Event Publicity

     Within ten (10) business days of the execution of this Agreement, AKAMAI
and Cidera shall jointly issue a press release at a mutually agreed upon time,
the specific content of which will be agreed to by both Parties.

     AKAMAI agrees to allow placement of a mutually agreed upon logo and
overview of this Agreement in Cidera's registration statement on Form S-1,
excepting those attachments marked "AKAMAI Confidential" contained herein.

     Cidera also agrees to promote throughout the Term, in its applicable press
releases and public announcements, AKAMAI as and, with respect to total
frequency, visibility, and content of Cidera's applicable publicity and
promotion activities, at least as prominently other similarly situated customers
of Cidera.

     Notwithstanding anything herein the contrary, all press releases,
announcements and other forms of publicity made by either Party concerning this
Agreement must be mutually approved by the Parties in writing which approval
shall not be unreasonably withheld. Neither Party shall disclose to third
parties, other than its agents and representatives on a need-to-know basis, the
terms of this Agreement or any Schedule hereto without the prior written consent
of the other party, except either party shall be entitled to disclose (i) such
terms to the extent required by law or as permitted pursuant to Section 8; and
(ii) the existence of this Agreement. Except as provided herein, no license or
conveyance of any rights to a Party's logos, trade marks, service marks,
customer list, or customer logos, trade marks or service marks is granted or
implied by either party under this Agreement

11.  Entire Agreement

     The Agreement, the NDA and the Attachments hereto constitute the entire and
exclusive understanding between the parties with respect to the subject matter
of this Agreement and supersedes all previous written or oral communications or
understandings between the Parties relating to the subject matter the Agreement.
The Agreement may be amended only in a writing signed by both Parties.


Executed and Agreed by:
<PAGE>

CIDERA, INC.                                    AKAMAI TECHNOLOGIES, INC.


By: /s/ Thom F. Degnan                          By: /s/ Avi Freedman
   ------------------------------                   --------------------------
Thom F. Degnan                                  Avi Freedman
Senior Vice President, Business                 Vice President & Chief Network
   Development                                     Architect
Cidera Inc.                                     Akamai Technologies, Inc.
8037 Laurel Lakes Drive                         500 Technology Square
Laurel, MD  20707                               Cambridge, MA  02139
<PAGE>

                                 ATTACHMENT A:

                         Cidera Service Coverage Areas

1.0  North America:

Cidera 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. Cidera has an agreement with TeleSat Canada for distribution within the
provinces of Canada.  The placement of the satellite dish will be by Cidera
following a site survey to assure line of sight to the satellite being utilized
by Cidera.

2.0  Europe:

Cidera provides the ability to delivery content via its GBON in Europe to the
Pan-European and Nordic Countries by placing 0.9 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 Cidera following a site
survey to assure line of sight to the satellite being used by Cidera.

3.0  Asia and Latin America:

Cidera is currently finalizing negotiations to provide similar services to these
areas and anticipates availability during the Year 2000.
<PAGE>

                                 ATTACHMENT B:

                   AKAMAI 7X24 Services Price Matrix[ * * * ]










*** Confidential Treatment Requested
<PAGE>

                                  ATTACHMENT C

                           AKAMAI Event Based Pricing

                                   [ * * * ]
<PAGE>

                                 ATTACHMENT D:

                                PROOF OF CONCEPT

                              AKAMAI CONFIDENTIAL

                                   [ * * * ]







*** Confidential Treatment Requested
<PAGE>

                                  ATTACHMENT E

                    SITE CONFIGURATION AND DIVISION OF COST

A.  ISP LOCATIONS:

1.  [ * * * ] provides the antenna, cabling, receiver and an Ethernet switch.

2.  [ * * * ] connects the ethernet switch to the [ * * * ] service adapter for
    [ * * * ] services.

3.  [ * * * ] connects the ethernet switch to the ISP LAN with a 100Mb
    connection.

4.  [ * * * ] installs its equipment and any cabling between [ * * * ] equipment
    and the Cidera switch

5.  [ * * * ] may connect to the [ * * * ] connection to the ISP LAN, or may
    install a separate connection to the ISP LAN.

B.  CO-LO FACILITIES:

1.  [ * * * ] provides the antenna, cabling, receiver and the ethernet switch.

2.  [ * * * ] connects the ethernet switch to the [ * * * ] service adapter for
    [ * * * ] services.

3.  [ * * * ] connects the ethernet switch to the ISP LAN with a 100Mb
    connection.

4.  [ * * * ] installs its equipment and any cabling between [ * * * ] equipment
    and the Cidera switch.

5.  [ * * * ] is responsible for its rack space, connection to the Co-location
    facility's local area network, and any outbound charges on the ISP Network.

C.  Cross Connect Charges:

1.  At sites where Akamai is already located, [ * * * ] will install the cross
    connect and incur any and all charges related to such installation.

2.  At sites where Cidera is already installed, [ * * * ] will pay for the cross
    connect.

3.  At new sites where neither Cidera nor Akamai is previously installed,
    [ * * * ].




*** Confidential Treatment Requested
<PAGE>

D.  ISP Rack Space:

    1.  [ * * * ] is responsible for the cost of rack space.  Typically, an edge
        strategy requires only a small amount of equipment to provide services
        to the customers of the ISP. [ * * * ].

E.  ISP LANs

    To date, ISPs are not charging for traffic on their LANs.  They could,
    however, charge [ * * * ] at some point in time in the future.



*** Confidential Treatment Requested


                       **********************************