<PAGE>   1
                                                                   EXHIBIT 10.15

                        CONFIDENTIAL TREATMENT REQUESTED



                         MASTER HIGH SPEED DATA SERVICES
                                    AGREEMENT

This MASTER HIGH SPEED DATA SERVICES AGREEMENT (this "Agreement") is entered
into as of the 12 day of November 1998 ("Effective Date"), by and between I(3)S,
INC., a Texas corporation, with an address at 1330 River Bend, Suite 600,
Dallas, Texas 75247-4953 ("I(3)S"); and GTE MEDIA VENTURES INCORPORATED, a
Delaware corporation, with an address at 100 East Royal Lane, HQJ02C05, Irving,
Texas 75039 ("GTE").

                                    RECITALS

WHEREAS, GTE currently provides wireless and wireline, cable television
programming and other services to multiple dwelling units ("MDUs") and their
residents in several metropolitan markets throughout the United States;

WHEREAS, I(3)S provides broadband network services, including, without
limitation, high speed data services, as more specifically described in Exhibit
D attached hereto and incorporated herein by reference ("HSDS"), to multiple
system franchise cable operators ("MSOs"), private cable operators ("PCOs"),
apartment owners, and real estate investment trusts ("REITs"), nationwide; and

WHEREAS, GTE desires to enter into an agreement with I(3)S to provide HSDS to
MDUs selected by GTE in its business judgment, in accordance with the terms of
this Agreement (collectively, the "Properties" and individually, a "Property").

NOW, THEREFORE, the parties hereto hereby covenant and agree as follows:

                                    ARTICLE 1
                         REPRESENTATIONS AND WARRANTIES

1.1    REPRESENTATIONS AND WARRANTIES OF GTE. In order to induce I(3)S to enter
       into this Agreement, GTE represents and warrants (which representations
       and warranties shall survive the delivery of this Agreement) as follows:

         (a) ORGANIZATION AND QUALIFICATION. GTE is a corporation duly organized
             and validly existing and in good standing under the laws of the
             State of Delaware; has all requisite power and authority to own its
             property and assets and to carry on its business as, and in the
             places where, such property and assets are owned or such business
             is now conducted; and is duly qualified to do business and is in
             good standing in every other jurisdiction in which such
             qualification is necessary or desirable.

         (b) NO DEFAULTS. GTE is not in default under any instrument or
             agreement existing as of the date hereof by which GTE is bound that
             may adversely



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GTE HSDS Agreement
<PAGE>   2

             affect its ability to perform its obligations under this Agreement;
             and no default hereunder has occurred and is continuing.

         (c) TITLE. GTE has good, valid and indefeasible title to its property
             that pertains in any way to the provision of HSDS on the
             Properties, and all such property is free and clear of all adverse
             claims, interests and liens, except as has been heretofore
             disclosed in writing to I(3)S.

         (d) ENFORCEABLE OBLIGATIONS; AUTHORIZATION. This Agreement is a legal,
             valid and binding obligation of GTE, enforceable in accordance with
             its terms; the making and performance by GTE of this Agreement have
             been duly authorized by all necessary action; are within the power
             and authority of GTE; will not contravene or violate any legal
             requirement or charter of GTE; and will not result in the breach
             of, or constitute a default under, any agreement, instrument,
             judgement, license, order, franchise or permit to which GTE is a
             party, or any of its property may be bound or affected.

         (e) PERMITS, LICENSES, ETC. GTE possesses all material permits,
             licenses, franchise rights, trademarks, trademark rights, trade
             names, trade name rights and copyrights which are required to
             conduct its business.

         (f) MDU PROPERTY AND OPERATING AGREEMENTS. All MDU property or
             operating agreements to which GTE is a party that pertain to the
             Properties are in full force and effect, and no default has
             occurred with regard to any such MDU property or operating
             agreement that would adversely affect the provision of HSDS at any
             of the Properties.

         (g) INSURANCE. GTE carries insurance with reputable insurers covering
             GTE's property pertaining to HSDS and to the business conducted
             thereby, in such amounts and against such risks as are necessary
             for the provision of services to the Properties.

         (h) RIGHT OF ACCESS. GTE possesses the right under contract or will
             obtain the contractual rights to allow an adequate contractual
             access or entry for the provision of HSDS to all Properties where
             HSDS is to be provided during the term of this Agreement in favor
             of I(3)S.

         (i) SURVIVAL OF REPRESENTATIONS AND WARRANTIES. All representations and
             warranties made by or on behalf of GTE shall survive the execution
             and delivery of this Agreement, and any investigation at any time
             made by or on behalf of I(3)S shall not diminish its rights to rely
             thereon.

1.2    REPRESENTATIONS AND WARRANTIES OF I(3)S. In order to induce GTE to enter
       into this Agreement, I(3)S represents and warrants (which representations
       and warranties shall survive the delivery of this Agreement) as follows:




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GTE HSDS Agreement
<PAGE>   3

         (a) ORGANIZATION AND QUALIFICATION. I(3)S is a Texas corporation duly
             organized and validly existing and in good standing under the laws
             of the State of Texas; has all requisite power and authority to own
             its property and assets and to carry on its business as, and in the
             places where, such property and assets are owned or such business
             is now conducted; and is duly qualified to do business and is in
             good standing in the State of Texas and in every other jurisdiction
             in which such qualification is necessary or desirable, including,
             but not limited to, any jurisdictions contemplated by this
             Agreement.

         (b) NO DEFAULTS. I(3)S is not in default under any instrument or
             agreement existing as of the date hereof by which I(3)S is bound
             that may adversely affect its ability to perform its obligations
             under this Agreement; and no default hereunder has occurred and is
             continuing.

         (c) TITLE. I(3)S has good, valid and indefeasible title to its property
             that pertains in any way to HSDS, and all such property is free and
             clear of all adverse claims, interests and liens, except as has
             been heretofore disclosed in writing to GTE.

         (d) ENFORCEABLE OBLIGATIONS; AUTHORIZATION. This Agreement is a legal,
             valid and binding obligation of I(3)S, enforceable in accordance
             with its terms; the making and performance by I(3)S of this
             Agreement have been duly authorized by all necessary action; are
             within the power and authority of I(3)S; will not contravene or
             violate any legal requirement, shareholders agreement of I(3)S, or
             articles of incorporation or bylaws of I(3)S; and will not result
             in the breach of, or constitute a default under, any agreement,
             instrument, judgement, license, order, franchise or permit to which
             I(3)S is a party, or any of its property may be bound or affected.


         (e) PERMITS, LICENSES, ETC. I(3)S possesses all material permits,
             licenses, franchise rights, trademarks, trademark rights, trade
             names, trade name rights, copyrights and all other applicable
             intellectual property rights which are required to conduct the
             business of HSDS and to perform I(3)S, obligations under this
             Agreement.


         (f) INSURANCE. I(3)S carries insurance with reputable insurers covering
             I(3)S's property pertaining to HSDS and to the business conducted
             thereby, in such amounts and against such risks as is necessary for
             the provision of HSDS to the Properties, including (1) minimum
             limits of $1,000,000 per occurrence for bodily injury or death, (2)
             property damage liability with limits of at least $1,000,000 per
             occurrence of personal injury, and (3) $1,000,000 General Policy
             Aggregate (applicable to commercial general liability policies).

         (g) I(3)S LICENSES. I(3)S possesses all requisite licenses and
             applicable intellectual property rights from third parties
             necessary to provide HSDS to the Properties and their residents.




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GTE HSDS Agreement
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         (h) SURVIVAL OF REPRESENTATIONS AND WARRANTIES. All representations and
             warranties made by or on behalf of I(3)S shall survive the
             execution and delivery of this Agreement, and any investigation at
             any time made by or on behalf of GTE shall not diminish its rights
             to rely thereon.


                                    ARTICLE 2
                                      TERM

2.1    TERM. The term of this Agreement, including the financial provisions
       pertaining thereto, shall be for five (5) years commencing on the
       Effective Date; provided, however, that with respect to each Property
       covered hereby, the term of this Agreement shall always be coterminous
       with the term (including any extensions thereof) of the individual GTE
       agreement with MDU property owners or management companies to provide
       cable antennae television, direct broadcast satellite or
       telecommunications services thereto.


                                    ARTICLE 3
                                   EXCLUSIVITY

3.1    EXCLUSIVITY. Although it is intended that GTE and I(3)S will offer and
       provide HSDS, respectively, to the Properties, as mutually agreed between
       the parties, in all metropolitan areas where GTE and I(3)S maintain
       operations, neither GTE nor I(3)S shall be precluded from entering into
       agreements with third parties to provide HSDS to such parties' customers
       thereunder. Notwithstanding the foregoing, GTE shall not market, sell,
       provide or promote, or cause to be marketed, sold, provided or promoted,
       directly or indirectly, a service which is competitive with HSDS, in
       whole or in part, to the Properties served by I(3)S under the terms and
       provisions, and during the term, of this Agreement; accordingly, GTE
       shall not proactively market any Internet access service that competes
       with HSDS on the Properties during the term hereof; provided, however,
       that for purposes of this Section 3.1, GTE's branded dial-up Internet
       access service or GTE's branded DSL service shall not be considered a
       competing service with HSDS.


                                    ARTICLE 4
                          AFFIRMATIVE COVENANTS OF GTE

4.1    In consideration of the mutual agreements of the parties contained
       herein, GTE unconditionally covenants and agrees to do and perform, or
       cause to be done and performed, the following:

         (a) GTE shall maintain, or cause to be maintained, in full force and
             effect an adequate right of entry, which permits I(3)S hereunder to
             provide HSDS to the Properties throughout the term of this
             Agreement.



GTE HSDS Agreement                                                             4
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         (b) GTE shall maintain its corporate existence and remain in good
             standing under the laws of and in every jurisdiction in which such
             qualification to do business is necessary or desirable for purposes
             of this Agreement.

         (c) GTE shall not knowingly become in default and remain in default
             under any instrument or agreement which GTE is bound that may
             adversely affect its ability to perform its obligations under this
             Agreement.

         (d) GTE shall possess and maintain good, valid, indefeasible and
             marketable title to its property that pertains in any way to its
             performance under this Agreement, and all such property shall
             remain free and clear of any adverse claims, interests and liens,
             except as has been heretofore disclosed in writing to I(3)S, or
             except for rights of subordination granted to lenders of MDU
             owners.

         (e) GTE shall maintain in full force and effect all material permits,
             licenses, franchise rights, trademarks, trademark rights, trade
             names, trade name rights and copyrights which are required to
             conduct its business.

         (f) GTE shall maintain in full force and effect all MDU property or
             operating agreements pertaining to the provision of HSDS to the
             Properties, but shall have the right, in its sole discretion, to
             terminate any such agreement as long as I(3)S has not yet placed
             equipment on the affected Property.

         (g) GTE shall maintain in full force and effect adequate insurance with
             reputable insurers covering GTE's property pertaining to HSDS, in
             such amounts and against such risks as is necessary for the
             provision of services to the Properties.

         (h) GTE shall use all commercially reasonable efforts to assist I(3)S
             in providing HSDS on Properties mutually selected by GTE and I(3)S
             on terms and conditions mutually acceptable to I(3)S and GTE; which
             Properties shall be added as Riders to Exhibit A attached hereto
             and incorporated herein by reference for all purposes; provided,
             however, that subject to I(3)S' right of first refusal set forth in
             Section 8.2 hereof, GTE shall identify the Properties to be
             submitted to I(3)S for the provision of HSDS under this Agreement,
             and is not required to submit all of its MDU properties for the
             provision of HSDS under this Agreement.

         (i) As more specifically described in Exhibit B attached hereto and
             incorporated herein by reference, for Properties covered by this
             Agreement, GTE shall assume the obligations and timely pay all
             operating and capital costs and expenses, if any, associated with
             any and all:




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GTE HSDS Agreement
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                (1) Monthly recurring on-site headend, cabling and wiring
                    maintenance for equipment and facilities owned by GTE

                (2) Leasing agent sales commissions and property owner revenue
                    sharing, if any, required under agreements between property
                    owners or managers and GTE

                (3) Insurance on GTE-owned capital equipment related to HSDS

                (4) GTE-specific training for HSDS

                (5) MDU property CATV or other cabling and wiring upgrades

                (6) Adequate on-site MDU space for the installation and
                    maintenance of I(3)S equipment

                (7) Reasonable access to residents' apartments for the
                    installation and maintenance of customer premise equipment

                (8) Customer service representatives (non-I(3)S personnel)

                (9) Periodic access to the rent roll pertaining to the
                    Properties if permitted by GTE's agreements pertaining to
                    the Properties


                                    ARTICLE 5
                         AFFIRMATIVE COVENANTS OF I(3)S

5.1    In consideration of the mutual agreements of the parties contained
       herein, I(3)S covenants and agrees to do and perform, or cause to be done
       and performed, the following:

         (a) I(3)S shall maintain its corporate existence and remain in good
             standing under the laws of the State of Texas and in every other
             jurisdiction in which such qualification to do business is
             necessary or desirable for its performance under this Agreement.

         (b) I(3)S shall not become in default under any instrument or agreement
             by which I(3)S is bound that may adversely affect its ability to
             perform its obligations under this Agreement.

         (c) I(3)S shall possess and maintain good, valid, indefeasible and
             marketable title to its property that pertains in any way to HSDS,
             and all such property shall remain free and clear of any adverse
             claims, interests and liens, except as has been heretofore
             disclosed in writing to GTE.

         (d) I(3)S shall maintain in full force and effect all material permits,
             licenses, franchise rights, trademarks, trademark rights, trade
             names, trade name rights, copyrights, and all other applicable
             intellectual property rights which are required to conduct the
             business of HSDS and to perform I(3)S' obligations under this
             Agreement.

         (e) I(3)S shall maintain in full force and effect adequate insurance
             with reputable insurers covering I(3)S's property pertaining to
             HSDS and to the conduct of the




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<PAGE>   7
             business pertaining thereto, in such amounts and against such risks
             as are necessary for the provision of HSDS to the Properties,
             including (1) minimum limits of $1,000,000 per occurrence for
             bodily injury or death, (2) property damage liability with limits
             of at least $1,000,000 per occurrence of personal injury, and (3)
             $1,000,000 General Policy Aggregate (applicable to commercial
             general liability policies).

         (f) As more specifically described in Exhibit C attached hereto and
             incorporated herein by reference, I(3)S shall assume and pay all
             operating and capital costs and expenses associated with any and
             all:

             (1)  Monthly recurring private Internet exchange points

             (2)  Monthly recurring switch maintenance

             (3)  Monthly recurring POP transport

             (4)  Monthly recurring Dallas network operations center costs
                  (including installation costs)

             (5)  Customer support IP technicians and engineers (NOC, Help Desk
                  and field personnel)

             (6)  I(3)S-specific training

             (7)  Insurance on I(3)S capital equipment

             (8)  Switch site equipment (including installation costs)

             (9)  Peering point routers

             (10) Private Internet exchange point hardware (including
                  installation costs)

             (11) I(3)S network infrastructure equipment

             (12) Transport facilities

             (13) Backbone transport facilities

             (14) Peering interconnection facilities

             (15) Recurring property maintenance (Lce, Router, DSU/CSU)

             (16) Recurring IP headend maintenance

             (17) CSR platform and services (non-GTE)

             (18) Internet browser platform user license

             (19) MDU property IP equipment (Lce, Router, DSU/CSU)

             (20) IP master headend equipment

             (21) Local loop transport costs

             (22) Customer billing and collections

             (23) HSDS marketing and promotion

             (24) Any other costs associated with providing HSDS

             (25) All activities referenced in Exhibit C to this Agreement


                                    ARTICLE 6
                   HIGH SPEED DATA SERVICES PROVIDED BY I(3)S

6.1    DESCRIPTION OF HSDS. During the term of this Agreement, I(3)S shall
       provide, or cause to be provided; the high speed data services, in whole
       or in part, more particularly described and set forth in Exhibit D.



GTE HSDS Agreement                                                             7
<PAGE>   8

6.2    HSDS SUBSCRIBER TERMS AND CONDITIONS. I(3)S and GTE shall jointly
       develop, in good faith, an HSDS Subscriber Agreement to govern the
       provision of HSDS on the Properties.


                                    ARTICLE 7
                          HSDS SERVICE LEVEL STANDARDS

7.1    DEFINITION OF HSDS SERVICE LEVEL STANDARDS. Subject to the conditions,
       qualifications and limitations set forth herein, including, without
       limitation, those set forth in Exhibit E attached hereto and incorporated
       herein by reference, during the term of this Agreement, I(3)S warrants
       and represents that it shall offer, or cause to be offered, and shall
       provide, or cause to be provided, HSDS at or exceeding the service level
       standards pertaining to various aspects of HSDS, as more particularly
       described and set forth in Exhibit E.


                                    ARTICLE 8
             REVENUE ALLOCATION; CUSTOMER ACCESS PRICING; BRANDING;
                               OTHER GTE SERVICES

8.1    REVENUE ALLOCATION. All monthly HSDS revenue generated by customers under
       the Agreement will be billed and collected by I(3)S throughout the term
       of the Agreement; provided, however, that, by the fifteenth (15th) day of
       each month I(3)S shall pay GTE a revenue sharing fee ("GTE Revenue
       Sharing Fee") calculated on the basis of customer access revenue
       (exclusive of, without limitation, customer premise equipment
       installation charges, customer service charges, customer equipment sales
       or leases, sums "passed through" on a no-mark up basis collected by or on
       behalf of I(3)S, and comparable or similar charges) actually collected by
       or on behalf of GTE and I(3)S for the immediately preceding month in
       accordance with the following table:

<TABLE>
<CAPTION>
           Penetration on Property                 GTE Revenue Sharing Fee
(Sum of the total number of paying customers   (Percentage of Gross Connectivity
             per day, per month                            Revenue)
   divided by the total units on property)


<S>                                            <C>
0% to 10%                                                     *
Greater than 10% to 15%                                       *
Greater than 15% to 20%                                       *
Greater than 20% to 30%                                       *
Greater than 30% to 40%                                       *
Greater than 40%                                              *
</TABLE>




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GTE HSDS Agreement
<PAGE>   9

8.2    MODIFICATION OF REVENUE SHARING FEES; RIGHT OF FIRST REFUSAL BY I(3)S;
       MOST FAVORED PARTNER PROVISION. GTE acknowledges and agrees that the
       Revenue Sharing Fees set forth above are predicated upon I(3)S providing
       HSDS to substantially all of the Properties mutually agreed between I(3)S
       and GTE. With respect to I(3)S' provision of HSDS to GTE MDU properties,
       I(3)S shall have the right of first refusal to provide HSDS to all MDU
       properties served or to be served by GTE where GTE provides or will
       provide satellite master antennae television, wireline CATV, or direct
       broadcast satellite services and has elected, in its business judgment,
       to offer HSDS to residents thereof. In the event that GTE presents an
       MDU property to I(3)S for the provision of HSDS, I(3)S shall either
       approve or refuse such MDU property within fifteen (15) business days
       from the date GTE first presents the MDU property to I(3)S for approval.
       In the event that I(3)S fails to respond within said fifteen (15) day
       period; it will be deemed to have refused the right to provide HSDS to
       said MDU property, unless the parties agree to extend said fifteen (15)
       day approval period. During the term of this Agreement, I(3)S shall offer
       GTE the most favored terms that I(3)S has then contracted for with other
       non-affiliated third party partners pertaining to HSDS in the MDU market
       for the same terms and conditions that GTE and I(3)S have entered into
       under this Agreement for all future Properties that become subject to
       this Agreement thereafter, unless said terms and conditions are less
       favorable than the terms and conditions hereof in which case GTE may
       elect to continue to adopt the terms and conditions of this Agreement.

8.3    CUSTOMER ACCESS PRICING; MARKET PLANS. With the intent to increase HSDS
       penetration at each of the Properties served under this Agreement, I(3)S
       shall upon consultation with GTE establish the price and rates at which
       access to the HSDS is made available to customers and end-users, the
       initial rates for which are set forth in Exhibit F attached hereto;
       provided, however, that in the event that I(3)S is generally providing
       access to the HSDS in the same Standard Metropolitan Statistical Area
       (SMSA) at subscriber rates which are substantially lower than the rates
       and prices I(3)S is then charging customers and end-users for the same
       access services hereunder, then upon written request by GTE, I(3)S shall
       lower the rates and prices hereunder to be competitive with the lower
       rates generally being charged by I(3)S for said access services in the
       same SMSA. Further, I(3)S shall remain competitive with the prices then
       being charged by other comparable high speed, broadband Internet access
       services generally being offered by commercial HSDS providers in the same
       SMSA. Marketing plans pertaining to HSDS on the Properties shall be
       established by I(3)S with significant input and advice from GTE, and
       subject to GTE's approval, which approval shall not be unreasonably
       withheld, delayed or conditioned.

8.4    BRANDING. With respect to HSDS, and the promotion thereof, upon
       consultation with GTE, I(3)S shall establish the brand names, logos,
       labels, trademarks, service marks and other such identifying promotional
       characteristics pertaining to the same throughout the term of this
       Agreement. It is intended by the parties that the HSDS will be branded
       BroadbandNOW!(TM), and I(3)S hereby grants to GTE a royalty-free,
       nonexclusive, nontransferable license during the term of this Agreement
       to use the




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<PAGE>   10

       BroadbandNOW(TM) name, service mark, trademark and logo in GTE's printed
       material and advertising of any kind pertaining to the offering of HSDS
       to MDU properties. Except as specifically set forth in this Agreement,
       nothing in this Agreement shall grant, suggest or imply any authority for
       one party to use the name, trademarks, service marks or trade names of
       the other for any purpose whatsoever. Without the prior written consent
       of GTE, which consent shall not be unreasonably withheld, delayed or
       conditioned, I(3)S shall not acquire any right to use, and shall not use,
       the name "GTE", the GTE logo, or any other GTE trademark or service mark
       known to I(3)S.

8.5    OTHER GTE SERVICES. With respect to other GTE services then being offered
       by GTE and its affiliates throughout the term of the Agreement that may
       be contracted for by I(3)S in connection with the provision of the HSDS
       hereunder and pursuant to other agreements or relationships with third
       parties, I(3)S and GTE shall negotiate in good faith to allow GTE or its
       affiliates the opportunity to provide such services to I(3)S on terms and
       conditions acceptable to I(3)S and at prices and rates which are
       competitive with other similar or comparable providers of such services
       in markets then being served by GTE, or as tariffed.


                                    ARTICLE 9
                        SPECIFIC HSDS SOFTWARE WARRANTIES

9.1    OWNERSHIP; AUTHORITY. I(3)S represents and warrants that the software
       utilized hereunder for the provision of HSDS (collectively, the
       "Products") are free and clear of all liens and encumbrances, and that it
       has full power and authority to utilize the rights granted to it with
       respect to such Products without the consent of any other person or that
       such consent has been obtained, and that to the knowledge of I(3)S the
       Products utilized hereunder will not infringe or violate any copyright,
       trade secret, trademark, patent or other intellectual property rights of
       any third party


                                   ARTICLE 10
                                 INDEMNIFICATION

10.1   INTELLECTUAL PROPERTY RIGHTS INDEMNIFICATION. I(3)S shall defend,
       indemnify and hold harmless GTE, its parent, subsidiaries, affiliates,
       directors, officers, shareholders, employees and agents and its
       successors and assigns, from and against any and all claims, demands,
       actions, liabilities, losses, damages and expenses, including, without
       limitation, settlement costs and reasonable attorneys' fees, arising out
       of or relating to any actual or alleged infringement of any third party's
       trade secrets, trademark, service mark, copyright, patent or other
       intellectual property rights (the "Intellectual Property Rights") in
       connection with the use of said Intellectual Property Rights hereunder.
       I(3)S's obligation pursuant to the immediately preceding sentence is
       subject to the following conditions: (i) GTE shall give I(3)S prompt
       written notice of all actions, claims or threats against GTE of




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<PAGE>   11

       infringement or violation of Intellectual Property Rights; (ii) GTE shall
       permit I(3)S to elect to assume complete control of such claims at its
       sole discretion and expense; provided, however, that GTE may elect, in
       such case, to retain its own counsel, at GTE's expense, to represent
       GTE's interest; and further, provided, however, that I(3)S will fully
       cooperate with GTE and keep it fully informed and refrain from entering
       into any settlement or agreed judgment without GTE's prior written
       consent, which consent shall not be unreasonably withheld, delayed or
       conditioned; and (iii) GTE shall cooperate fully with I(3)S in defending
       against claims, including making known or available to the indemnifying
       party, upon reimbursement of all costs associated with provision or
       reproduction of, all records and document pertaining to claims.

10.2   CROSS INDEMNIFICATION FOR OBLIGATIONS UNDER THIS AGREEMENT. Each party
       hereby agrees to indemnify, defend and hold harmless the other party from
       any and all damages, liabilities, costs and expenses, including, without
       limitation, reasonable attorneys' fees and expenses, arising out of,
       under or in connection with the indemnitor party's duties, obligations,
       actions or performance under this Agreement, or the indemnitor party's
       gross negligence or willful misconduct.


10.3   LIMITATION OF LIABILITY. It is expressly understood that GTE makes no
       projection, representation or warranty regarding the amount of revenue
       that may be earned by I(3)S under this Agreement. Neither party shall be
       liable to the other party for any indirect, incidental, special, or
       consequential damages of any kind whatsoever; provided, however, that
       this limitation of liability shall not apply to either party's
       indemnification obligations under this Agreement.


                                   ARTICLE 11
                        PROTECTION OF PROPRIETARY RIGHTS

11.1   DEFINITION. During the term of this Agreement, I(3)S and GTE will provide
       to each other or will come into possession information relating to each
       other's business which is considered confidential or proprietary (the
       "Confidential Information"). Confidential Information shall include,
       without limitation, the HSDS software and documentation, all of I(3)S's
       and GTE's trade secrets and all know-how, design, invention, plan or
       process and information relating to I(3)S's and GTE's respective business
       operations, services, products, research and development and all other
       information that is marked "confidential" or "proprietary" prior to or
       upon disclosure, or which, if disclosed orally, is identified by the
       disclosing party as being Confidential Information in writing within
       thirty (30) days after its initial disclosure.

11.2   RESTRICTIONS; NON-DISCLOSURE; NON-USE. Each party shall use its best
       efforts to maintain the confidentiality of such Confidential Information
       and not show or otherwise disclose such Confidential Information to any
       third parties, including, but




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<PAGE>   12

       not limited to, independent contractors and consultants, without the
       prior written consent of the disclosing party. Each party shall use the
       Confidential Information solely for purpose of performing its obligations
       under this Agreement. Further, neither party shall use or exploit,
       directly or indirectly, the Confidential Information of the other party.
       There shall be no implied license granted to the receiving party by the
       disclosing party to use Confidential Information by virtue of the
       disclosure of such Confidential Information hereunder. Each party shall
       indemnify and hold harmless the other party from any loss or damage the
       other party may sustain as a result of the wrongful use or disclosure by
       such party (or any employee, agent, licensee, contractor, assignee or
       delegatee of the other party) of its Confidential Information.

11.3   AUTHORIZED DISCLOSURES. Notwithstanding the obligations described in
       Section 9.2 above, neither party shall have any obligation to maintain
       the confidentiality of any Confidential Information which: (i) is or
       becomes publicly available by other than unauthorized disclosure, by the
       receiving party; (ii) is independently developed by the receiving party
       without reference to Confidential Information of the disclosing party as
       established by documentary evidence in the receiving party's files; or
       (iii) is received from a third party who has lawfully obtained such
       Confidential Information without a confidentiality restriction. If
       required by any court of competent jurisdiction or other governmental
       authority, the receiving party may disclose to such authority, data,
       information or material involving or pertaining to Confidential
       Information to the extent required by such order, provided that the
       receiving party shall first have used its best efforts to obtain a
       protective order reasonably satisfactory to the disclosing party
       sufficient to maintain the confidentiality of such data, information or
       materials.

11.4   LIMITED ACCESS. Each party shall limit the use and access of Confidential
       Information to such party's bonafide employees or agents who have a need
       to know such information for purposes of conducting the receiving party's
       business. Each party shall notify all employees and agents who have
       access to Confidential Information or to whom disclosure is made that the
       Confidential Information is the confidential, proprietary property of the
       disclosing party and shall instruct such employees and agents to maintain
       the Confidential Information in confidence.

11.5   CONTINUING OBLIGATIONS. Each party's obligations under this Article 9
       shall survive the termination of this Agreement for three (3) years
       thereafter.


                                   ARTICLE 12
                     DEFAULT; EARLY TERMINATION; EXPIRATION

12.1   DEFAULT. Upon the occurrence of any of the following events, a party
       shall be deemed to be in default under this Agreement:

         (a) Material breach of any warranty or representation by the defaulting
             party;




                                                                              12
GTE HSDS Agreement
<PAGE>   13

         (b) Material failure to perform the defaulting party's obligations
             hereunder, including with respect to I(3)S its failure to (i)
             maintain the service standards set forth in Section 7.1 hereof, and
             (ii) make the payments to GTE set forth in Section 8.1 hereof.

         (c) The defaulting party's ceasing to conduct business in the normal
             course, insolvency, the making of a general assignment for the
             benefit of its creditors, suffering or permitting the appointment
             of a receiver or similar officer for its business or assets or
             availing itself of, or becoming subject to, any proceeding under
             the United States Federal Bankruptcy Laws or any federal or state
             statute relating to solvency or the protection of the rights of
             creditors; or

         (d) Making of any warranty, representation, statement or response in
             connection with this Agreement which was untrue in any material
             respect on the date it was made by the defaulting party.

12.2   REMEDIES. In the event the defaulting party fails to cure any default set
       forth hereunder for a period of thirty (30) days after written notice of
       such default by the non-defaulting party, the non-defaulting party may
       terminate this Agreement without further obligation on the part of the
       non-defaulting party, and pursue any claims at law or in equity against
       the defaulting party.

12.3   FAILURE TO EXERCISE REMEDY. The remedies set forth above are cumulative,
       but the non-defaulting party is under no obligation to exercise any such
       remedy. The exercise of, or failure to exercise, any such remedies shall
       not prevent any future exercise of the same or any other remedies or
       release the defaulting party from its obligations under this Agreement.

12.4   EFFECT OF TERMINATION. Early termination or expiration of this Agreement
       shall not impair either party's then accrued rights, obligations,
       liabilities or remedies hereunder.

12.5   EXAMINATION; AUDIT RIGHTS. I(3)S agrees that GTE has the right to audit
       or otherwise examine, or have audited or otherwise examined, on an annual
       basis all applicable books, records, documents, and other data of I(3)S,
       including computations and projections, specifically and only relating to
       the GTE Revenue Sharing Fee under this Agreement, and I(3)S' billing and
       collection of revenues from HSDS subscribers. If GTE's audit reveals that
       GTE has been underpaid its GTE Revenue Sharing Fee by a percentage in
       excess of five percent (5%) over the period of the audit, I(3)S shall pay
       GTE's reasonable costs of the audit, in addition to paying all past due
       amounts owed to GTE. I(3)S shall make available at its principal place of
       business at all reasonable times during normal business hours the
       materials described in the first sentence of this Section 12.5 for
       examination, audit, or reproduction. In the event that this Agreement is
       completely or partially terminated, the records relating to the GTE
       Revenue Sharing Fee shall be made




                                                                              13
GTE HSDS Agreement
<PAGE>   14

       available for two (2) years after any termination of this Agreement.
       Records pertaining to appeals or to litigation or the settlement of
       claims arising under or relating to either party's performance under this
       Agreement shall be made available until disposition of such appeals,
       litigation or claims.


                                   ARTICLE 13
                           NOTICE; PUBLIC DISCLOSURES

13.1   NOTICE. Any notice, demand or other communication required or permitted
       by any provision of this Agreement shall be deemed to have been
       sufficiently given or served for all purposes when delivered in person or
       sent by registered or certified mail, return receipt requested, all
       postage and other charges prepaid, to the respective addresses of the
       parties first noted above, or at such other address as may be designated
       by notice from such party to the other party pursuant to their terms of
       this section. In addition, a copy of all notices given to GTE under this
       Agreement shall be sent to: Sandra Skogen, Law Department, GTE
       Communications Corporation, 6665 North MacArthur Blvd., Irving, Texas
       75039; 972-465-4826 (Fax).


13.2   PUBLIC DISCLOSURES. All media releases, public announcements, and public
       disclosures by either party of its employees, agents or representatives
       relating to this Agreement or the subject matter hereof, excluding any
       announcement beyond the control of this disclosing party, will be
       approved by the non-disclosing party in writing prior to release.


                                   ARTICLE 14
                                  MISCELLANEOUS

14.1   ENTIRE AGREEMENT. This Agreement, together with the schedules,
       attachments and exhibits attached hereto or referred to herein,
       constitutes the entire Agreement and understanding among the parties
       hereto and is the final expression of their Agreement and no evidence of
       oral or other written promises shall be binding. All other prior
       agreements or understandings related to the subject hereof among the
       parties, whether written or oral, shall be null and void and of no
       further force and effect upon the execution of this Agreement. This
       Agreement shall be binding upon and inure to the benefit of the parties
       hereto and their respective successors and permitted assigns.

14.2   INCORPORATION BY REFERENCE. The schedules, exhibits and attachments
       referred to herein or attached hereto are hereby incorporated in and to
       this Agreement and made a part hereof by this reference.

14.3   AMENDMENT; MODIFICATION. This Agreement may not be supplemented, amended,




                                                                              14
GTE HSDS Agreement
<PAGE>   15
       modified or otherwise altered except by written instrument executed by
       all the parties hereto and no course of dealing or trade usage among or
       between the parties shall be effective to supplement, amend, modify or
       alter this Agreement.


14.4   WAIVER. The failure to enforce or to require the performance at any time
       of any of the provisions of this Agreement herein shall in no way be
       construed to be a waiver of such provisions, and shall not affect either
       the validity of this Agreement, any part hereof or the right of any party
       thereafter to enforce each and every provision in accordance with the
       terms of this Agreement.

14.5   GOVERNING LAW. THIS AGREEMENT SHALL BE GOVERNED BY AND CONSTRUED IN
       ACCORDANCE WITH THE LAWS OF THE STATE OF TEXAS, WITHOUT REGARD TO ITS
       CONFLICTS OR CHOICE OF LAWS. VENUE FOR ANY ACTION BROUGHT UNDER THIS
       AGREEMENT SHALL BE IN DALLAS, DALLAS COUNTY, TEXAS.

14.6   SEVERABILITY. If any severable provision of this Agreement is deemed
       invalid or unenforceable by any judgment of a court of competent
       jurisdiction, the remainder of this Agreement shall not be affected by
       such judgment, and this Agreement shall be carried out as nearly as
       possible according to its original terms and intent, unless to do so
       would substantially impair the underlying purposes of this Agreement.

14.7   CAPTIONS. The captions appearing in this Agreement are included solely
       for convenience of reference and shall not be construed or interpreted to
       affect the meaning or interpretation of this Agreement.

14.8   FORCE MAJEURE. Neither party shall be responsible for any failure to
       comply with or for any delay in performance of the terms of this
       Agreement, including, but not limited to, delays in delivery, where such
       failure or delay is directly or indirectly caused by or results from
       events of force majeure beyond the control of either party. These events
       shall include, but not be limited to, fire, flood, earthquake, accident,
       civil disturbance, war, acts of God, or acts or government.

14.9   HIRING PROHIBITED. Unless otherwise mutually agreed between the parties,
       during the term of this Agreement and for a period of one (1) year
       thereafter, neither party shall solicit for hire or hire any employee of
       the other party who has performed services under this Agreement.

14.10  PERFORMANCE REVIEW. In the event of any dispute or controversy between
       the parties of any kind or nature, upon the written request of either
       party, each of the parties will appoint a designated officer whose task
       it will be to meet for the purpose of resolving such dispute or
       controversy or to negotiate for an adjustment to any provision of this
       Agreement needed to resolve such dispute or controversy. Such officers
       will discuss the dispute or controversy and negotiate in good faith in an
       effort to resolve the dispute or controversy or renegotiate the
       applicable section




                                                                              15
GTE HSDS Agreement
<PAGE>   16

       or provision of this Agreement without the necessity of any formal
       proceeding relating thereto. No formal proceedings for the judicial or
       arbitrational resolution of such dispute or controversy may be commenced
       until either or both of the designated officers conclude in good faith
       that an amicable resolution through continued negotiation of the matter
       at issue is not likely to occur, or until thirty (30) days have elapsed
       from the date of the written request, whichever is sooner.


14.11  BINDING NATURE; ASSIGNABILITY. This Agreement will be binding on the
       parties hereto, and their respective successors and assigns. Upon prior
       written notice to the other party, either party may assign its rights and
       delegate its duties under this Agreement; provided however, that the
       assignee party must unconditionally assume in writing, and agree to be
       bound by, the right, duties and obligations of the assignor party under
       this Agreement. Notwithstanding this section, no consent is required for
       an assignment of this Agreement by GTE to a parent, subsidiary or
       affiliate.

14.12  RELATIONSHIP OF THE PARTIES. Notwithstanding anything to the contrary in
       this Agreement, under no circumstances will either party be deemed to be
       in any relationship with the other party carrying with it fiduciary or
       trust responsibilities. The parties do not intend for this Agreement or
       the relationship established thereby to be considered the formation of a
       joint venture or partnership between the parties for any purpose. The
       persons provided by each party for the performance of its obligations
       hereunder shall be solely that party's employees and shall be under the
       exclusive direction and control of that party. They shall not be
       considered employees of the other party for any purpose. Each party shall
       be responsible for compliance with all laws, rules and regulations
       involving, but not limited to, employment of labor, hours of labor,
       health and payment of taxes, including federal, state and municipal
       taxes, chargeable or assessed with respect to its employees, such as
       Social Security, unemployment, workers' compensation, disability
       insurance, and federal and state withholding. Each party shall indemnify
       the other party for any loss, damage, liability, claim, demand, or
       penalty that may be sustained by reason of its failure to comply with
       this provision.

14.13  COMPLIANCE WITH APPLICABLE LAWS. Each party represents and warrants that
       the services performed by such party pursuant to this Agreement shall be
       in compliance with all applicable federal and state laws, rules and
       regulations.




                                                                              16
GTE HSDS Agreement
<PAGE>   17

IN WITNESS WHEREOF, the parties hereto have executed this Agreement as of the
date first above written.


I(3)S, INC.                                      GTE MEDIA VENTURES INCORPORATED


By: /s/ MATTHEW HUTCHINS                         By: /s/ WILLIAM D. WILSON
    --------------------                             ---------------------------
    Matthew Hutchins                             Title: President
    Vice President, Business Development               --------------
     & Corporate Affairs                         Printed Name: William D. Wilson
                                                               -----------------


Date: 11/4/98                                    Date: 11/12/98
      ------------------                               -------------------------


                                                                         [STAMP]


                                                 APPROVED AS TO FORM
                                                 /s/ KATHLEEN E. PALTER 11-10-98
                                                 -------------------------------
                                                       KATHLEEN E. PALTER
                                                        GTE LEGAL DEPT.




                                                                              17
GTE HSDS Agreement
<PAGE>   18

                                    EXHIBIT A
                               MDU PROPERTY RIDERS

                           FORM OF MDU PROPERTY RIDER
                         (Type of Information Required)



1.   MDU Property Owner/Agent: ________

2.   Term of Property Agreement: ________

3.   Acknowledgement by Owner of Right of HSDS Access to Property.

4.   Location of MDU Property: ________

5.   Contact Person/Leasing Agent: ________

6.   CATV/MATV Site Survey Information:

7.   Number of Units: ________

8.   Number of Buildings: ________

9.   Current Occupancy: ________

lO.  Existing Property (including age) or New Build: ________

11.  PC Ownership Survey: ________

12.  Existing/Proposed Local Loop Trunking:




                                                                              18
GTE HSDS Agreement
<PAGE>   19

                                    EXHIBIT B

                              PROPERTY NETWORK AND
                           LOCAL LOOP CHARACTERISTICS

GTE'S RESPONSIBILITIES:

o    Build or obtain exclusive access to and maintain CATV infrastructure to
     comply with FCC requirements.

o    Build or obtain exclusive access to and maintain property CATV
     infrastructure to provide bi-directional cable delivery to all subscribers.

o    Maintain the upgraded bi-directional CATV infrastructure to exceed the
     minimal operational requirements of the I(3)S cable modem system, which
     are:

<TABLE>
<CAPTION>
Minimum Cable Television Network Requirements                Value
              for i3s.net HSDS
<S>                                               <C>

Amplitude variations inband
  Forward channel                                 5 dB total
  Return channel                                  5 dB total

Group delay variation inband
  Forward channel                                  60 nsec/MHz, 240 nsec total
  Return channel                                  200 nsec/MHz, 800 nsec total

Maximum tap to tap variation                      27 dB

Dynamic range on receiver                         -15 dBmV to +15 dBmV

Maximum return/upstream loss                      49 dB

Minimum carrier to noise                          22 dB

Minimum carrier to interference                   25 dB
</TABLE>


Provide, or cause to be provided, two (2) six MHz video channels within the CATV
infrastructure bandwidth on Internet served properties; one (1) in the spectrum
from 54 MHz to 750 MHz and one (1) in the 5MHz to 50 MHz spectrum; and reserve
another two (2) additional video channels, in the same spectrums for future
expansion as Subscriber penetration on the property increases.

Provide, or cause to be provided, proper space, security and power for data
communication equipment necessary to provide Internet delivery and other data
services on the property.

Provide, or cause to be provided, coaxial connection (coax drop) to each
Subscriber's unit. Designate an engineering point of contact for I(3)S Network
Operations Center (NOC) to report problems or failures twenty-four hours per
day, seven days per week (24x7).



I(3)S / GTE Media Ventures Exhibits                                 Confidential




<PAGE>   20
                                    EXHIBIT C
                                POINT OF PRESENCE
                     FEATURES AND ESTABLISHMENT REQUIREMENTS

I(3)S RESPONSIBILITIES:

     Install, maintain and operate data delivery equipment for each property
     offering HSDS. Installation and maintenance will meet or exceed
     manufacturer's specifications. Through itself or its agents, GTE will
     assist I(3)S with pre-installation engineering planning and site survey
     questionnaires, installation, testing and preparation of maintenance
     schedules.

     Integrate all data delivery equipment for each property into the I(3)S
     Element Management System portion of its Network Management Platform using
     SNMP and RMON. I(3)S will monitor all data delivery equipment twenty-four
     hours per day, seven day per week (24x7).

     Assume the cost of the acquisition of I(3)S-specified data communication
     equipment conforming to the I(3)S design for HSDS and necessary to provide
     termination and delivery of HSCS between the Subscriber and the I(3)S POP
     in each Market.

     Order, provision, install and maintain local loop pathways between each
     property and I(3)S POP in each Market with a bandwidth of not less than
     1.544 mb/s (T1). In addition, as the number of Subscribers on each property
     increases, scale the local loop bandwidth so that each simultaneously
     active user averages approximately 1 mb/s ninety eight percent (98%) of the
     time. Both parties acknowledge that the end-to-end performance of HSDS is
     probabilistic and subject to anomalous short-lived usage patterns by
     Subscribers which will affect both the utilization of the local-loop
     circuits and the I3s.net national backbone from time to time.

     Configure and operate all data delivery equipment to efficiently integrate
     with the rest of the I3s.net network.

     Acquire, install and maintain data communication equipment at each POP for
     the termination and transmission of HSDS from properties to the i3s.net
     national network backbone.

     I(3)S will determine the location of its main presence in each Market to be
     consistent with its own operational practices (which currently include
     co-locating within its carrier's central offices in each Market).

     Acquire, install, maintain and operate Internet peering relationships at
     public and private Internet Exchange Points (EP) with other Tier 1 Internet
     backbone networks throughout the United States.

     Acquire, install, maintain and operate computers and software to provide
     Network Management and provide Internet services for Subscribers. To
     provide these functions, I(3)S will employ a combination of
     locally-distributed-to-the-POP servers as well as globally centralized
     servers consistent with its overall network design and operational
     practices.

     Order, provision, install, maintain and operate data transport/carriage
     pathways from each POP, EP and/or NOC with a bandwidth not less than 45
     mb/s (DS-3) interconnection. In addition, as the number of Subscribers on
     Market increases, scale the bandwidth so that each simultaneously active
     user averages approximately 1 mb/s ninety eight percent (98%) of the time.
     Both parties acknowledge that the end-to-end performance of HSDS is
     probabilistic and subject to anomalous short-lived usage patterns by
     Subscribers which will affect both the utilization of the local-loop
     circuits and the i3s.net national backbone from time to time.



I(3)S / GTE Media Ventures Exhibits                                 Confidential




<PAGE>   21

                              EXHIBIT C (CONTINUED)

                               CUSTOMER HELP LINE
                          SERVICE AND REQUIRED FEATURES

 I(3)S RESPONSIBILITIES

          Provide toll free numbers for:

                  Inquires about the HSDS product
                  Ordering and scheduling installation of HSDS products
                  Billing inquiries
                  Initial technical support inquires

          Operate 24x7 customer service call center operation.

          Maintain sufficient customer service staff and call center capacity to
          connect to Subscribers within 5 minutes of call entering processing
          operation.

          Resolve billing issues within 24 hours 95% of time.

          Resolve property network issues within 24 hours 95% of time.

          Develop and publish escalation procedure for Help Desk and attendants
          related to network issues.

          Provide toll free number for:

                  Technical support for all HSDS issues
                  Technical support for Subscriber CPU hardware and software
                  issues related to HSDS Technical support for cable modem
                  issues

          Answer toll free line consistent with the GTE/I(3)S service co-brand

          Operate 24x7 customer service call center operation.

          Maintain sufficient customer service staff and call center capacity to
          connect to Subscribers within 5 minutes of call entering processing
          operation.

          Resolve technical issues within 24 hours if a phone call is required
          95% of time.

          Resolve technical issues within 48 hours if a truck roll is required
          95% of time.

          Develop and publish escalation procedure for Help Desk and attendants
          related to network issues.

          Develop and publish escalation procedures for GTE to contact regarding
          technical issues related to the network.

          Provide training support for GTE's customer service representatives
          (train-the-trainer support).



I(3)S / GTE Media Ventures Exhibits                                 Confidential




<PAGE>   22

                              EXHIBIT C (CONTINUED)

                 SUBSCRIBERS' HARDWARE AND SOFTWARE INSTALLATION
                  SPECIFICATIONS AND INSTALLATION REQUIREMENTS

I(3)S SHALL:

          Verify that potential Subscribers' personal computers meet the
          I(3)S-established minimum requirements for the supplied software and
          the HSDS service.

          Make an appointment with each new Subscriber to meet the I(3)S
          installation personnel for the installation of the HSDS in the
          Subscriber's unit.

          Supply I(3)S with Subscribers' information required to install,
          provision and complete the set up of Subscribers' HSDS service. GTE
          and I(3)S will jointly develop an appropriate paper-form-based system
          or automated system to facilitate this process.

          Provide, or cause to be provided, coaxial connection to the
          Subscriber's specified location.

          Verify, or cause to be verified, that the coaxial connection completed
          to the Subscriber's specified location exceeds the minimum operational
          requirements for the I(3)S/supplied cable modem and the I(3)S HSDS
          service.

          Verify, or cause to be verified, that all CATV services function
          properly after I(3)S completes installation.

          Maintain a sufficient inventory of cable modems for each Market and
          develop procedures to restock cable modems as used in Subscriber
          installations.

          Issue and install the required number of cable modems for the service
          requested by the Subscriber.

          Meet the Subscriber at the Subscribers location at the scheduled time
          within the tolerances and limits as defined in the I(3)S Service Level
          Agreement.

          Install the required cable modems(s) in the Subscriber's unit.

          Install any required network interface cards (NICs), TCP/IP protocols
          and Internet software suite in the Subscriber's personal computer.

          Offer the Subscriber a brief introduction to the HSCS to be performed
          at the time of installation. This introduction will include how to
          launch the service, how to find the training material on the i3s.net
          Web site, how to find the Subscriber Support Section on the i3s.net
          Web site and how to call for technical assistance or support.

          Obtain signatures required to verify that installation was executed
          properly and to the satisfaction of the Subscriber.

          Provide GTE with a copy of the installation transaction documentation
          verifying that the completed installation is ready for billing. This
          documentation will include the cable modem delivery receipt, the ISP
          contract and the completed work order.



I(3)S / GTE Media Ventures Exhibits                                 Confidential




<PAGE>   23

                              EXHIBIT C (CONTINUED)

                       PROCEDURES FOR DETECTION AND NOTICE
                 OF GTE PROPERTY NETWORK OR LOCAL LOOP FAILURES


I(3)S SHALL:

          Use the cable modem system, and certain network management features
          that it provides, to monitor the availability and quality of GTE's
          property network (its CATV plant).

          Report to GTE's designated engineering point of contact any problems
          observed by the I(3)S NOC in the course of operating the cable modem
          system network management features.

          Report to GTE's designated engineering point of contact any problems
          determined by Subscriber contact in the course of operating the
          Subscriber Help Desk.

          Offer to GTE a read-only direct computer interface into the I(3)S
          cable modem system's network management platform for the purposes of
          direct observation of the information produced by the management
          platform and possible enhancement of GTE's Property network
          operations. If GTE elects to implement a read-only direct-computer
          interface, GTE will be responsible for all of the costs associated
          with such an interface.



I(3)S / GTE Media Ventures Exhibits                                 Confidential




<PAGE>   24

                                    EXHIBIT D

                  DEFINITION OF HIGH-SPEED DATA SERVICES (HSDS)
                            FEATURES AND REQUIREMENTS

The I(3)S HSDS includes:

     o    Data Network services that provide transport and peering functions to
          the global Internet, including, without limitation:

               o    A broadband access network on MDU properties composed of one
                    or more headend reference nodes, a coaxial or hybrid fiber
                    coaxial (HFC) cable television distribution system and one
                    or more cable data modems (CDM);

               o    A local loop network that connects the headend reference
                    node on each MDU property to the I(3)S regional
                    point-of-presence (POP) in each metropolitan area served by
                    I(3)S;

               o    A regional point-of-presence network that connects the POP
                    to the i3s.net national Internet backbone;

               o    A national Internet backbone consisting of broadband
                    communication facilities for the transport of data among
                    I(3)S POPs and public and private Exchange Points where data
                    and Internet routing information will be exchanged with
                    other networks peered with i3s.net;

               o    A national Network Operations Center (NOC).

     o    Certain computer services that include.

               o    Membership system for user authentication and authorities;

               o    Personalization services for customizing content to user
                    preferences;

               o    Internet mail (SMTP and POP3);

               o    Internet newsgroups (NNTP) composed of approximately 25,000
                    newsgroups;

               o    Internet World Wide Web (HTTP) services;

               o    Internet chat (IRC and MIRC);

               o    White-pages-style directory services;

               o    Internet locator services;

               o    Conferencing and collaboration bridges;

               o    Streaming multimedia services such as Microsoft's NetShow
                    and Progressive Network's RealMedia;

               o    Electronic commerce services.

     o    A branded suite of client software that include:

               o    Web browser;

               o    Mail reader;

               o    News reader;

               o    Chat client;

               o    Conferencing and collaboration client;

               o    Appropriate plug-ins and ActiveX controls.

     o    Certain customer service functions that include:



I(3)S / GTE Media Ventures Exhibits                                 Confidential




<PAGE>   25

               o    A National Customer Care Center;

               o    A telephone and network-based customer help desk;

               o    A Trouble Reporting facility;

               o    A customer billing system.

     o    Certain multimedia-rich content that showcases the capabilities of
          HSDS that includes:

               o    Original content created by I(3)S;

               o    Aggregated content created by others but licensed by I(3)S
                    and improved for uses in a HSDS system;

               o    Aggregated content created by others but licensed by I(3)S
                    and used unimproved.



I(3)S / GTE Media Ventures Exhibits                                 Confidential




<PAGE>   26

                                    EXHIBIT E
INTRODUCTION

              This Exhibit entitled "Service Level Agreement" ("SLA") sets out
              operation specifications and requirements for HSDS provided by
              I(3)S for the residents or customers of GTE Media Ventures
              Incorporated (herein sometimes called "Teaming Associate"). The
              SLA shall encompass data services originating and terminating
              within the I(3)S internetwork ("i3s.net").

              The HSDS provided by I(3)S shall meet the operations specification
              and requirements stated herein, which are generally stated in
              terms of events or outcomes, rather than terms of specific
              hardware, software or procedural requirements. For the purposes of
              the SLA, i3s.net shall relate to that portion of the global
              Internet operated by I(3)S, originating within end users' customer
              premises and terminating within I(3)S computers or transported and
              peered at a public or private Internet Exchange Point.

              For the purposes of the SLA, a "Trouble" or "Trouble Report" shall
              relate to i3s.net or I(3)S provided services (or resold services),
              but shall exclude customer error, defects in "customer premises
              equipment" ("CPE"), defects in customers' computers, defects in
              distribution coaxial cable, defects in distribution fiber optics
              defects in cable television systems and network problems
              experienced by destination networks at or beyond Internet Exchange
              Points.


PERFORMANCE REQUIREMENTS

              PERCENT CUSTOMER SERVICE ORDER BEGINNING COMMITMENT DATES TIMELY
              MET

                       This parameter is generally indicative of the timely
                       beginning of work on orders from customers for new
                       service or orders to make changes in their existing
                       service.

                       The timely beginning parameter is calculated by dividing
                       the total Customer Service Orders begun on or before the
                       date and clock hour promised to the customer that the
                       service order would be started by the total number of
                       service orders initiated in each calendar month and
                       multiplying by 100.

                       I(3)S shall exhibit greater than 90% Customer Service
                       Order Beginning Commitment Dates Timely Met per month.


              PERCENT CUSTOMER SERVICE ORDER COMPLETION COMMITMENT DATES TIMELY
              MET

                       This parameter is generally indicative of the timely
                       completion of work on orders from customers for new
                       service or orders to make changes in their existing
                       service and the timely completion of those service
                       orders.

                       The timely completion parameter is calculated by dividing
                       the total Customer Service Orders completed on or before
                       the date and clock hour promised to the customer that the
                       service order would be completed by the total number of
                       service orders initiated in each calendar month and
                       multiplying by 100.

                       I(3)S shall exhibit greater than 90% Customer Service
                       Order Completion Commitment Dates Timely Met per month.



                                                         Service Level Agreement
                                                                     Page 1 of 4




<PAGE>   27

              PERCENT OF NETWORK AVAILABILITY

                       This parameter is generally indicative of the
                       availability of the network to transport and peer
                       customer data at an Internet Exchange Point, or, in the
                       event that the customer data is to be fulfilled by
                       computers within i3s.net, generally indicative of the
                       availability of to transport data to the I(3)S servers
                       and the availability of the servers.

                       This parameter is calculated by dividing the number of
                       seconds that the network is available for each customer
                       by the total number of customer-seconds in each calendar
                       month and multiplying by 100.

                       Specifically excluded from the Network Availability
                       calculation shall be regularly scheduled maintenance
                       windows or ad hoc maintenance windows scheduled and
                       announced 24 hours in advance in the i3s.net Customer
                       Support Web Site.

                       Specifically excluded from the Network Availability
                       calculation shall be periods of time where the cable
                       television distribution plant (operated by the Teaming
                       Associate or its designated third party operator) exceed
                       the follow table of acceptable values:


<TABLE>
<S>                                         <C>
Amplitude Variation Inband Upstream         1 dB/MHz., 5 dB total
---------------------------------------------------------------------------
Amplitude Variation Inband Downstream       1 dB/MHz., 5 dB total
---------------------------------------------------------------------------
Group Delay Variation Inband Upstream       200 nsec./MHz., 800 nsec. total
---------------------------------------------------------------------------
Group Delay Variation Inband Downstream     60 nsec./MHz., 240 nsec. total
---------------------------------------------------------------------------
Tap to Tap Level Variation                  <27 dB
---------------------------------------------------------------------------
</TABLE>


                       I(3)S shall exhibit greater than 98% Network Availability
                       per month.


              PERCENT CUSTOMER CALLS ANSWERED within 45 Seconds by I(3)S
              PERSONNEL

                       This parameter is based upon the number of customers
                       calls answered within 15 seconds by a human operator or
                       by an ACD queue greeting during the hours of operation of
                       the I(3)S National Customer Care Center and thereafter to
                       be answered by a customer representative with 30 seconds.
                       At a minimum, the I(3)S National Customer Care Center
                       shall operate from 8:00 a.m. to 5:00 p.m. Central Time,
                       Monday through Friday exclusive of holidays.

                       This parameter is calculated by dividing the number of
                       calls answered with 45 seconds by the total number of
                       calls answered seconds in each calendar month and
                       multiplying by 100.

                       I(3)S shall exhibit greater than 90% of Customer Calls
                       Answered within 45 Seconds per month.


              PERCENT OF TROUBLE REPORTS RESOLVED TIMELY

                       This parameter is related to the number of Trouble
                       Reports resolved within the following windows:

                           o  For Trouble Reports received by I(3)S at the I(3)S
                              National Customer Care Center prior to 2:00 p.m.
                              Central Time, Monday through Friday, excepting
                              holidays, will be cleared by the end of the next
                              business day.



                                                         Service Level Agreement
                                                                     Page 2 of 4




<PAGE>   28

                           o  For Trouble Reports received by I(3)S at the I(3)S
                              National Customer Care Center after 2:00 p.m.
                              Central Time, Monday through Friday, excepting
                              holidays, will be cleared by noon of the second
                              business day thereafter.

                       This parameter is calculated by dividing the total
                       trouble reports cleared on or before the date and clock
                       hour promised to the customer the total number of Trouble
                       Tickets cleared in each calendar month and multiplying by
                       100.

                       I(3)S shall exhibit greater than 90% Trouble Reports
                       Cleared Timely per month, according to the terms of this
                       section for trouble that can be resolved by I(3)S alone.


              PERCENT CUSTOMER REPAIR VISIT APPOINTMENTS MET

                       This parameter is related to the customer commitments
                       made by the I(3)S National Customer Care Center for
                       repairs that require a repair visit to customers' sites
                       or premises.

                       This parameter is calculated by dividing the total
                       Customer Repair Visits Appointments met on or before the
                       date and clock hour promised to the customer by the total
                       number of Customer Repair Visit Appointments initiated in
                       each calendar and multiplying by 100.

                       I(3)S shall exhibit greater than 90% Customer Repair
                       Commitment Met per month.


              PERCENT OF CUSTOMER BILLS PREPARED TIMELY

                       This parameter is related to the generation of Customer
                       Bills for delivery to customers by mail, electronic mail
                       or credit card billing.

                       This parameter is calculated by dividing the number of
                       Customer Bills generated and sent to customers within
                       twenty (20) business days of the end of the billing cycle
                       by the total number Customer Bills generated in each
                       calendar month and multiplying by 100.

                       I(3)S shall exhibit greater than 95% Customer Bills
                       Prepared Timely per month.


              PERCENT OF CUSTOMER BILLS PREPARED ACCURATELY

                       This parameter is related to the accuracy of Customer
                       Bills for delivery to customers by mail, electronic mail
                       or credit card billing.

                       This parameter is calculated by dividing the number of
                       Customer Bills generated that do not require an
                       adjustment due to a billing error caused I(3)S by the
                       total number Customer Bills generated in each calendar
                       month and multiplying by 100.

                       I(3)S shall exhibit greater than 95% Customer Bills
                       Prepared Accurately per month.


REPORTS



              I(3)S shall undertake commercially reasonable efforts to provide
              to Teaming Associates reports within twenty (20) business days of
              the end of each calendar month, the reports listed below in this
              section, each of which may be provided separately or provided on a
              consolidated basis:



                                                         Service Level Agreement
                                                                     Page 3 of 4




<PAGE>   29

                       A report depicting total subscribers, gross new customers
                       and gross customers terminated separated by product tier
                       and property.

                       New service orders, Trouble Reports opened and closed or
                       cleared as appropriate separated by date and property.

                       Aggregate I(3)S National Customer Care Center data
                       depicting the distribution of call waiting time in
                       general and the percent calls answered and calls
                       abandoned respectively.

                       Billing summaries describing the date(s) bills were sent
                       to customers, and the billed revenue disaggregating major
                       categories of service.


HOLIDAYS

              New Years Day


              Memorial Day

              Independence Day

              Labor Day

              Thanksgiving

              Day after Thanksgiving

              Christmas

              And any other holiday recognized by I(3)S



                                                         Service Level Agreement
                                                                     Page 4 of 4




<PAGE>   30

                                    EXHIBIT F

                  HSDS INITIAL SUBSCRIBER RATES, SERVICE LEVELS
                     AND INSTALLATION AND EQUIPMENT CHARGES


Initial Subscriber charges shall be:

<TABLE>

<S>                                                              <C>
         64 kb/s contention-based non-burstable                  $29.95 per month
         1.00 mb/s contention-based burstable                    $39.95 per month
         1.54 mb/s contention-based with reserved bandwidth      $79.95 per month

         Small office, home office (SOHO)                        $500.00 per month
         Vanity DNS hosting                                      $100.00 per month

         Installation fee                                        $99.00 non-recurring
         Network interface card (NIC)                            market price (assumed to be $60)

         LanCity LCp cable modem purchase                        $395.00 non-recurring
         Monthly rental of LCp                                   initially $10.00 per month
</TABLE>



I(3)S / GTE Media Ventures Exhibits                                 Confidential