MASTER ALLIANCE AGREEMENT

                                    BETWEEN

                         iBEAM BROADCASTING CORPORATION

                                      AND

                          WILLIAMS COMMUNICATIONS, LLC

THIS MASTER ALLIANCE AGREEMENT (this "Agreement") between Williams
Communications, LLC ("Williams"), a Delaware limited liability company, and
iBEAM Broadcasting Corporation, a Delaware corporation, ("iBEAM"), is effective
the ___ day of _____________, 2001 (the "Effective Date"). Williams and iBEAM
are individually referred to as a "Party" and collectively referred to as the
"Parties."

                                    RECITALS

WHEREAS, iBEAM has an Internet broadcast network that delivers streaming media
services and solutions to the Enterprise and Entertainment and Media markets;

WHEREAS, iBEAM desires to use Williams for all telecommunications-related
services in connection with iBEAM's Internet broadcast network, and Williams
desires to have a right of first offer and a right of first refusal with respect
to iBEAM's purchase of such services;

WHEREAS, Williams is a nationwide, single source provider of network services
for delivery of data on a wholesale basis and of video transmission and storage
services;

WHEREAS, the capabilities of each Party are complementary, and the relationship
contemplated by this Agreement (the "Alliance") will serve to broaden the base
of potential competitive opportunities for telecommunications services and other
applications for all market segments;

WHEREAS, the Parties are entering into a series of additional agreements to
implement the Alliance; and

WHEREAS, the Parties are entering into this Master Alliance Agreement to set
forth general provisions concerning the Alliance.

NOW THEREFORE, in consideration of the mutual covenants herein contained, iBEAM
and Williams agree as follows:


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1. Other Alliance Agreements

The Parties have previously entered into the following agreements: (1) a
Teleport Services Agreement dated December 13, 1999 (the "Teleport Services
Agreement"); and (2) a Data Services Agreement dated March 19, 2001 (the "Data
Services Agreement"). The Parties are now entering into the following additional
agreements to implement the Alliance, in addition to this Agreement: (3)
Amendment No. 1 to the Digital Services Agreement; and (4) a mediaXtranet
Services Agreement (the "mXn Agreement"). Collectively, these agreements,
together with this Agreement, are referred to as the "Alliance Agreements," and
copies of the other Alliance Agreements are attached hereto as follows:

         Exhibit A - Teleport Services Agreement
         Exhibit B - Data Services Agreement, as amended by Amendment No. 1
         Exhibit C - mXn Agreement

2. Preferred Provider

It is the intent of the Parties that, subject to the terms hereof, Williams
shall be the preferred provider of the Services (as defined below) to iBeam, and
that iBeam shall receive favorable pricing for Services obtained pursuant to
this Alliance Agreement.

A. For purposes of this Agreement a "Service" shall mean any of the following:

            o     ATM Service
            o     Frame Relay Service
            o     Private Line Service
            o     Transit Internet Service
            o     Dedicated Internet Service
            o     Optical Wave Service
            o     Colocation Service
            o     Network Monitoring, including network control center services
                  and other Professional Services
            o     Customer Care Services, including help desk
            o     Hosting of World Wide Web Sites and Content
            o     Digital Data Management
            o     Digital Data Storage
            o     Caching Service
            o     Internet Connectivity
            o     Satellite and Teleport Distribution Services
            o     Media Exchange (or Digital Data Distribution)
            o     Video Transmission / Backhaul Services

      Williams may update or modify the foregoing list of Services from time to
time upon written notice to iBEAM to reflect changes in Williams' standard
service offerings.


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B. If written contracts in addition to the Alliance Agreements are needed to
govern any Services, then Williams and iBEAM will negotiate in good faith to
execute services agreements or amendments to govern the provision of such
Services from Williams to iBEAM. Until these written services agreements have
been executed, Williams' standard terms and conditions shall govern any
provision of such Services to iBEAM.

C. iBEAM hereby grants to Williams a right of first offer (the "RFO") and a
right of last refusal (the "RLR") to sell Services to iBEAM, subject to and in
accordance with the following:

      (i) Right of First Offer. In the event that iBEAM desires to purchase a
      service that is the same as or substantially similar to a Service, iBEAM
      shall so notify Williams in writing and Williams shall have the right to
      present a written proposal to provide a Service to iBEAM before iBEAM
      seeks proposals from third parties. If Williams does not respond within
      five (5) business days after receipt of such notice from iBEAM, with
      either a)a written proposal or b) a notice that it intends to submit a
      written proposal, iBEAM shall have the right to seek proposals from third
      parties. If the service sought by iBEAM is one for which a proposal cannot
      reasonably be delivered by Williams within such five (5) day period, then
      Williams shall have a reasonable time period within which to submit a
      proposal, such reasonable time period not to exceed a date beyond which
      iBEAM would be unable to seek and consider proposals from third parties
      and to submit same to Williams as required by the RLR.

      (ii) Right of Last Refusal.

            a. In the event that iBEAM receives a bona fide proposal from a
      third party (a "Proposal") to provide a service to iBEAM that is the same
      as or substantially similar to a Service, iBEAM shall offer Williams the
      opportunity to make a proposal to iBEAM to provide such Service on the
      same terms as those contained in the Proposal (a "Matching Proposal").

            b. Williams shall have no less than five (5) business days after
      receipt of such notice from iBEAM of the terms of a Proposal in which to
      deliver to iBEAM notice that it intends to submit a written proposal or a
      written Matching Proposal, in which case iBEAM shall either (a) agree to
      the Matching Proposal within five (5) business days after receipt thereof,
      or (b) decline the Matching Proposal, in which case iBEAM shall not accept
      the Proposal either. If Williams does not deliver a written Matching
      Proposal to iBEAM within such time period, iBEAM shall have the right to
      purchase the service from the third party pursuant to the Proposal free
      and clear of any obligation to Williams under this RLR.

            c. The Parties acknowledge that end users of iBEAM at times may
      request iBEAM to use an alternative provider for services falling within
      the scope of the RFO


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      and/or RLR. In such event, iBEAM shall in good faith inform the end user
      of iBEAM's strategic relationship with Williams and, if Williams so
      requests, use reasonable efforts to arrange a meeting between
      representatives of Williams, representatives of iBEAM, and representatives
      of the end user in order to attempt to persuade the end user to use
      Williams instead of the alternative vendor. If the end user nevertheless
      requests that iBEAM use an alternative provider, then such transaction
      shall not be governed by the RFO or the RLR.

      (iii) Acceptance of Proposal. If Williams chooses to bid on services
      pursuant to subsection c (i) or c (ii) above, and Williams' bid is
      competitive with the overall market price for any specific service, then
      Williams will be awarded the project, provided that Williams' bid contains
      substantially similar commercial terms as any Proposal that would
      otherwise be selected by iBeam. The Parties agree that "overall market
      price" shall mean pricing available on a nationwide basis, disregarding
      segment specific pricing and promotional pricing, for services that are
      substantially the same as the services provided to iBeam by Williams. The
      Parties will attempt to resolve any disagreement regarding what is
      competitive with respect to any given Service.

D. The RFO and the RLR shall also be binding on iBEAM's Affiliates. An
"Affiliate" shall be an entity that controls, is controlled by, or is under
common control with a Party. Additionally, this provision shall survive any
change of "Control," as defined herein, of either Party and shall be binding
upon the entity resulting from the change of Control.

4. No Resale

It is the intent of the Parties that the Services are for the use of iBEAM only
to use to support its Internet broadcast network that delivers streaming media
services and solutions. Accordingly, iBEAM shall not resell any Services to
third parties. For example, iBEAM is receiving rack space as part of the hosting
Services under the mXn Agreement. iBEAM shall not resell that rack space to
third parties.

5. Term

The Term of this Alliance Agreement shall continue in effect for the shorter of
(a) five (5) years after the Effective Date, or (b) the date that Williams and
its Affiliates, in the aggregate, hold less than ten percent (10%) of the voting
rights associated with iBEAM's capital stock.

6. Alliance Managers

The "Alliance Manager" is an individual appointed by each Party and dedicated to
managing the Alliance relationship. iBEAM and Williams will each designate one
Alliance Manager from within their respective organizations. It shall be the
responsibility of the Alliance Manager to:

A.    Serve as the principal contact person for each Party to the other
      concerning Alliance matters;

B.    Expedite the accomplishment of Alliance projects;


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C.    Coordinate the activities of the Parties in furtherance of the goals of
      the Alliance;

D.    Seek any necessary internal approvals that may be necessary and desirable
      to conduct the business of the Alliance.

7. Alliance Planning

The Parties shall establish formal reviews not less frequently than each
calendar quarter. These meetings shall review iBEAM's needs for Services, and
any current issues regarding Williams' Services. The Alliance Managers shall
jointly call the meetings.

8. Common Infrastructure Platform

The Parties will work in good faith to develop a Future Infrastructure Plan. The
Future Infrastructure shall provide for a content delivery network that is
capable of delivering streaming services, for both live streams and non-live
content to iBEAM and Vyvx customers.

The Parties agreed to proceed with the following phased approach in this regard:

      Phase 1: A team of technical, operations and finance experts from each
party will develop, by July 30, 2001, an implementation plan for the IP and
collocate services to be provided by Williams ;

      Phase2: The team's second deliverable will be to prepare, by September 30,
2001, a high level network and systems topology for a Next Generation
Intelligent Streaming Platform, complete with identification of major
milestones, proposed schedules, and budgetary estimates for capital and expense
impacts.. This plan to be reviewed by the Parties and decisions reached as to
funding and implementation timing within the next 30 days after presentation of
the initial high level plan.

      Phase 3: Given appropriate adjustments for operational and financial
considerations, the goal for the implementation of the Future Infrastructure
Plan will be to complete the implementation by June 30, 2002, after which point
the Future Infrastructure will serve as the traffic network and system for iBeam
and Vyvx traffic.

iBeam agrees not to implement a Future Infrastructure Plan with any Party other
than Williams.

9. Intellectual Property

A.    Definitions

      (i) "Arbitration Panel" shall mean a panel of three arbitrators, none of
      whom shall be an employee of iBEAM or Williams or an Affiliate of iBEAM or
      Williams. One arbitrator shall be appointed by iBEAM, one arbitrator shall
      be appointed by Williams, and the third arbitrator shall be appointed by
      the two existing arbitrators. No potential


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      arbitrator may serve on the Arbitration Panel unless he or she has had
      experience valuing software technology. All aspects of any arbitration
      before the Arbitration Panel shall be treated as confidential. Neither
      iBEAM, Williams, nor the Arbitration Panel may disclose the existence,
      content or results of any such arbitration, except as necessary to comply
      with legal or regulatory requirements. Before making any such disclosure,
      a party shall give written notice to all other parties and shall afford
      such parties a reasonable opportunity to protect their interests. Any
      determination by the Arbitration Panel shall be binding on iBEAM and
      Williams.

      (ii) "Current Assets" shall have the meaning as defined by Generally
      Accepted Accounting Principles ("GAAP").

      (iii) "End User" shall not include any entity that has the right to
      sublicense the iBEAM Software Applications to others, or provide ASP or
      time-sharing access to the iBEAM Software Applications, including
      distributors, carriers, and service providers, but rather, includes
      entities who are using the iBEAM Software Applications to provide Streams
      to their end viewers.

      (iv) "iBEAM Software Applications" shall mean, collectively,
      PowerPresenter V.1., WebCast Encoder V.1., WebCast Scheduler V.1., WebCast
      NV Service V.1., WebCast Media Indexer V.1., Telephony System V.1.,
      Internet Real-Time Text Transmission V.1., 5.0 Authentication Plug-In
      V.1., Virtual Roadshow Administration V.3., Virtual Roadshow Client User
      Interface V.3., Transporter Administration V.3., Transporter Service V.3.,
      Publisher Service V.3., Producer V.3., NextVenue W. Media Server Security
      DLL V.1., and NextVenue Media Server Security DLL V.1.

      (v) "Revenue" shall have the meaning as defined by GAAP.

      (vi) "Streams" shall mean individual instances of simultaneously
      downloaded and viewed or listened to audio and/or video content.

      (vii) "Trigger Event" shall mean any one or more of the following: (i) 20%
      decrease in the monthly volume of Streams served in any two consecutive
      months exclusive of December by iBEAM (measured against the last 12 months
      moving average); (ii) decrease in Revenue by more than 25% in any given
      quarter, as compared to the immediately prior quarter; (iii) decrease in
      iBEAM's Current Assets below an amount equal to $10 million; (iv) decrease
      in iBEAM's net cash and equivalents by more than $10 million in any
      calendar quarter beginning in the first quarter of 2002; (v) loss of more
      than 50% of iBEAM's sales force; or (vi) loss of more than 33% of the
      development and support staff for the iBEAM Software Applications,
      exclusive of any reductions as contemplated by the Business Plan (as
      defined in the letter agreement re: Business Plan of even date herewith
      between the Parties).

B. Most Favored Pricing. During the term of this Agreement, in the event that
iBEAM makes or received an offer (and "Offer") for the sale, lease, license or
other disposition of the iBEAM Software Applications, or any part thereof, in
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of business as such business is conducted by iBEAM as of the date hereof, and
except for the provision of an iBEAM Software Application via a site license to
an individual iBEAM End User solely for the purpose of installation and use of
an iBEAM Software Application. If iBEAM intends to sell, lease, license or
otherwise dispose of an iBEAM Software Application pursuant to the terms of an
Offer, then, prior to the consummation of such transaction, iBEAM shall offer to
Williams in writing (a "Williams Offer") the right to acquire the same rights on
terms that are equivalent to the Offer. If Williams does not accept the Williams
Offer in writing within thirty (30) days after receipt thereof, Williams shall
be deemed to have rejected the Williams Offer. iBEAM represents and warrants to
Williams that, as of the date hereof, no third party has any rights in and to
the iBEAM Software Applications other than pursuant to iBEAM's standard Reseller
Agreement, a copy of such Reseller Agreement is attached hereto as Exhibit D, on
terms consistent with those having been offered to Williams, and pursuant to
licensing agreements between iBEAM and iBEAM Europe Limited and between iBEAM
and iBEAM Asia Ltd.

C. License Grant

      (i) License Grant. iBEAM hereby grants to Williams, a royalty-bearing
      (solely in accordance with Section 9.C.(iii) ("Royalty") below),
      non-exclusive, transferable, sublicensable right to copy, modify, use (in
      object code and source code form), distribute, create derivative works
      from, and display the iBEAM Software Applications (the "License"), which
      License shall become exercisable by Williams solely upon the occurrence of
      one or more of the Trigger Events.

      (ii) License Term. During the period beginning on the occurrence of one or
      more of the Trigger Events and continuing thereafter for a period of
      ninety (90) days (the "Cure Period"), the License may be exercised by
      Williams for so long as the Trigger Event(s) which prompted the License
      remain uncured by Williams as substantiated by detailed written
      documentation. In the event that iBEAM does not cure any such Trigger
      Event(s) during the Cure Period and provide Williams with such
      substantiating documentation, at Williams' option, (i) the License shall
      thereafter either be perpetual and may not be revoked by iBEAM at any
      time, or (ii) Williams may acquire the iBEAM Software Applications at the
      fair market value to be determined by the Arbitration Panel.

      (iii) Royalty. Upon the first commercial use of the iBEAM Software
      Applications by Williams pursuant to the License, Williams shall pay to
      iBEAM a monthly licensing fee equal to the fair market value for the
      licensing of similar software to be set by the Arbitration Panel. In the
      event that Williams chooses to acquire the iBEAM Software Application
      (pursuant to Section 9.C.(ii) ("License Term") above), Williams shall no
      longer be required to pay iBEAM any further monthly licensing fee.

      (iv) Software Support. If Williams exercises such License, for the term of
      any such License, iBEAM shall provide Williams the maintenance services
      set forth in Exhibit E, at fair market rates as set by the Arbitration
      Panel.


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D. Escrow Agreement. iBEAM, Williams and a nationally recognized escrow agent
selected by iBEAM and Williams shall enter into a standard source code escrow
agreement ("Escrow Agreement") providing Williams with access to the
then-current current source code and documentation for the iBEAM Software
Applications (the "Source Material") upon the occurrence of certain listed
events, including, without limitation, the Trigger Events and iBEAM's
bankruptcy. Such Source Material shall include, without limitation, source code
and documentation required for the normal use, maintenance, modification or
correction of the most current version of the iBEAM Software Applications.
Williams shall have the right to audit the Source Material to verify the
accuracy and completeness thereof. iBEAM shall ensure execution of same by the
escrow agent within [ten (10) days] after the Effective Date and provide
Williams with a true copy of the fully executed escrow-agent-executed copy of
the Escrow Agreement.

10. Further Agreements

Further agreements to implement the Alliance may be appropriate. Therefore, upon
reasonable request of a Party, the Parties shall meet and negotiate in good
faith to determine if additional Alliance agreements are appropriate and the
terms and conditions of any such agreements.

11. Assignment

Neither Party may assign nor delegate any of its rights or obligations under
this Agreement without the prior written consent of the other Party. However,
either Party may assign this Agreement to any Affiliate, so long as such
assigning Party guarantees the Affiliate's performance, and in such circumstance
shall provide the other with written notice thereof.

12. Amendment

No amendment of this Agreement shall be valid or binding on the Parties unless
such amendment shall be in writing and duly executed by an authorized
representative of each Party.

13. Breach, Cure and Termination

If iBEAM breaches any Alliance Agreement in a manner that has a material adverse
effect on the commercial value of the Alliance to Williams, and does not cure
such breach within fifteen (15) days after receipt of written notice from
Williams explaining in reasonable detail the basis of such breach, then Williams
shall have the right to terminate all or part of the Alliance upon not less than
ten (10) business days' prior written notice to iBEAM. If Williams breaches any
Alliance Agreement in a manner that has a material adverse effect on the
commercial value of the Alliance to iBEAM, and Williams does not cure such
breach within fifteen (15) days after receipt of written notice from iBEAM
explaining in reasonable detail the basis of such breach, then iBEAM shall have
the right to terminate all or part of the Alliance upon ten (10) business days'
prior written notice to Williams.

14. Cross-Default

In the event that iBeam materially breaches any of its obligations,
representations, warranties or covenants under any of the Transaction Documents
(as this term is defined under the Stock Purchase Agreement between Williams and
iBeam, dated June __, 2001), and does not cure such


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breach within fifteen (15) days after receipt of written notice from Williams
explaining in reasonable detail the basis of such breach, then Williams shall
have the right to terminate the Alliance upon not less than ten (10) business
days' prior written notice to iBeam. In the event that Williams materially
breaches any of its obligations, representations, warranties or covenants under
any of the Transaction Documents, and does not cure such breach within fifteen
(15) days after receipt of written notice from iBeam explaining in reasonable
detail the basis of such breach, then iBeam shall have the right to terminate
the Alliance upon not less than ten (10) business days' prior written notice to
Williams.

15. Headings

Headings contained herein shall in no way limit the subject matter they
introduce and shall not be used in construing this Agreement.

16. Publicity

Neither Party shall make a public announcement about this Agreement or the
Parties' discussions related to any aspect of it without the written consent of
the other Party. Either of the Parties may at anytime make announcements which
are required by applicable law, regulatory bodies, or stock exchange or stock
association rules, so long as the Party so required to make the announcement,
promptly upon learning of such requirement, notifies the other Party of such
requirement and discusses with the other Party in good faith that exact wording
of any such announcement.

17. Execution

This Agreement shall be executed in two duplicate copies, one for each Party,
each of which copies shall be deemed an original.

18. Relationship of Parties

The Alliance Agreements individually or in the aggregate shall not be construed
to create a partnership, joint venture, or any other form of legal entity.

19. Notices

Any notice, request, instruction or other document to be given hereunder by any
Party to any other Party under any section of this Agreement shall be in writing
and shall be given by facsimile with confirmation by overnight courier. to the
following addresses (or at such other address for a Party as shall be specified
by like notice):

             If to iBEAM:          iBEAM Broadcasting Corporation
                                   645 Almanor Avenue, Suite 200
                                   Sunnyvale, CA 94085
                                   Attn: General Counsel
                                   Fax: (408) 524-0567
                                   Telephone: (408) 830-3543


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             If to Williams:       Williams Communications, LLC
                                   One Williams Center, MD-27
                                   Tulsa, OK 74172
                                   Attn: Contract Administration
                                   Fax: 918-573-6578
                                   Telephone: 918-573-6277

             With a copy to:       Williams Communications, LLC
                                   One Williams Center, Suite 4100
                                   Tulsa, OK 74172
                                   Attn: General Counsel
                                   Fax: 918-573-3005
                                   Telephone: 918-573-5057

20. Severability

In case any one or more of the provisions contained in this Agreement shall for
any reason be held to be invalid, illegal or unenforceable in any respect by a
court or other authority of competent jurisdiction, such invalidity, illegality
or unenforceability shall not affect any other provision hereof, and this
Agreement shall be construed as if such invalid, illegal or unenforceable
provision had never been contained herein and, in lieu of each such illegal,
invalid or unenforceable provision, there shall be added automatically as a part
of this Agreement a provision as similar in terms to such illegal, invalid or
unenforceable provision as may be possible and be legal, valid and enforceable,
it being the intent of the Parties to maintain the benefit of the bargain for
both Parties.

21. Governing Law

This Agreement shall be construed in accordance with and governed by the laws of
the State of Delaware. .

22. Entire Agreement

This Agreement, together with the other Alliance Agreements attached as Exhibits
hereto, which are incorporated herein, contains the entire agreement of the
parties with respect to the subject matter hereof and supersedes any prior
understandings, oral agreements and/or writings between the Parties regarding
the subjects within this Agreement.


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IN WITNESS WHEREOF, the Parties hereto have caused this Agreement to be executed
by their respective authorized representatives.

WILLIAMS COMMUNICATIONS, LLC              iBEAM BROADCASTING CORPORATION


/s/ John Bumgarner                        /s/ Peter Desnoes
------------------                        -----------------
Signature of Authorized Representative    Signature of Authorized Representative

-----------------------------             Peter Desnoes
Printed Name                              -------------
                                          Printed Name
-----------------------------
Title                                     CEO
                                          ---
                                          Title


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Source: OneCLE Business Contracts.