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                                                                   EXHIBIT 10.18



                        CONFIDENTIAL TREATMENT REQUESTED



                         MASTER HIGH SPEED DATA SERVICES
                                    AGREEMENT


       THIS MASTER HIGH SPEED DATA SERVICES AGREEMENT (this "Master Agreement")
is entered into as of the 22nd day of June 1999, by and between I(3)S, Inc., a
Texas corporation, with a place of business at 1440 Corporate Drive, Irving
Texas 75038 ("I3S"); and SEREN INNOVATIONS, INC., a Minnesota corporation with a
place of business at 15 South 5th Street, Suite 500, Minneapolis, MN 55402
("SEREN"). I3S and SEREN are hereinafter sometimes individually referred to as a
"party", and collectively as the "parties".

                                    RECITALS

       WHEREAS, SEREN is developing multiple franchise cable television systems
(collectively, "MSOs") in various markets throughout the United States;

       WHEREAS, I3S provides broadband Internet protocol network Services,
including, without limitation, those high speed data services, which are more
specifically described in the Exhibits attached hereto and incorporated herein
by reference (the "HSDS"), to multiple system franchise cable operators
nationwide; and

       WHEREAS, SEREN and I3S desire to exclusively provide HSDS to the Hybrid
Fiber Coaxial System (HFC) Networks owned or operated by SEREN, and listed in
Exhibit C, pursuant to the terms and provisions of this Agreement which, in
part, gives I3S an exclusive right of access to provide HSDS to such HFC
Networks.

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

                                    ARTICLE 1
                         REPRESENTATIONS AND WARRANTIES

       1.1    REPRESENTATIONS AND WARRANTIES OF SEREN.

       AUTHORITY.  This Agreement has been duly authorized, executed and
delivered by SEREN and constitutes a valid and legally binding Agreement of
SEREN, and neither the execution and delivery, nor the performance, of the
provisions of this Agreement shall conflict with or result in (a) a breach,
violation or default under the Certificate of Incorporation and Bylaws of SEREN,
if applicable; or any material agreement binding on SEREN that would affect its
obligations hereunder; or (b) the breach or violation of any law, order, rule,
ordinance, regulation, judgement or decree of an governmental authority having
jurisdiction.


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       SURVIVAL OF REPRESENTATIONS AND WARRANTIES.  All representations and
warranties made by or on behalf of SEREN shall survive the execution and
delivery of this Agreement, and any investigation at any time made by or on
behalf of I3S shall not diminish its rights to rely thereon.

       1.2    REPRESENTATIONS AND WARRANTIES OF I3S.

       AUTHORITY.  This Agreement has been duly authorized, executed and
delivered by I3S and constitutes a valid and legally binding Agreement of I3S,
and neither the execution and delivery, nor the performance, of the provisions
of this Agreement shall conflict with or result in (a) a breach, violation or
default under the Certificate of Incorporation and Bylaws of I3S, if applicable;
or any material agreement binding on I3S that would affect its obligations
hereunder; or (b) the breach or violation of any law, order, rule, ordinance,
regulation, judgement or decree of an governmental authority having
jurisdiction.

       PERMITS, LICENSES, ETC. I3S possesses all material permits, licenses,
franchises rights, trademarks, trademark rights, trade names, trade name rights
and copyrights which are required to conduct the business of HSDS.

       I3S LICENSES. I3S possesses all requisite licenses from third parties
necessary to provide the HSDS to the HFC Network.

       SURVIVAL OF REPRESENTATIONS AND WARRANTIES. All representations and
warranties made by or on behalf of I3S shall survive the execution and
delivery of this Agreement, and any investigation at any time made by or on
behalf of SEREN shall not diminish its rights to rely thereon.

                                    ARTICLE 2
                                      TERM

       2.1   TERM.  This Master Agreement shall have an initial term of ten
(10) years from the Effective Date; provided, however, that the initial term may
be automatically extended after the tenth anniversary of the Effective Date for
additional one (1) year terms unless one party provides the other party with
prior written notice, delivered no earlier than 180 days prior to the expiration
of initial term (or any renewal thereof) of this Master Agreement, of the
notifying party's intent to terminate this Master Agreement. Notwithstanding
anything contained in this Section 2.1 to the contrary, with respect to the HFC
Network pertaining to St. Cloud, Minnesota, the initial term of this HFC Network
Agreement shall be seven (7) years from the Effective Date. With respect to each
additional HFC Network that becomes subject to this Agreement, the initial term
of this Agreement pertaining thereto shall be either the later of (i) six (6)
years commencing on the date that the HSDS are first provided at said HFC
Network, or (ii) five (5) years commencing on the date that SEREN completes the
construction of the two-way hybrid fiber coaxial cable distribution plant past
100,000 prospective HSDS subscribers.


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                                    ARTICLE 3
                                   EXCLUSIVITY

       3.1    EXCLUSIVITY. During the term of this Agreement, neither party
shall provide, market or support, or cause to be provided, marketed or
supported, directly or indirectly, a competitive service to HSDS which is
deployed over the I3S national IP backbone to said HFC Network franchise service
area except in accordance with the terms and conditions hereof; provided,
however, that (i) for HFC Networks listed in Exhibit C at the date of signing
this Master Agreement, I3S shall not be precluded from providing HSDS under
other agreements with third parties that have been entered into prior to the
date of signing this Master Agreement; (ii) for future Seren HFC Networks not
listed in Exhibit C at the date of signing this Master Agreement, I3S shall not
be precluded from providing HSDS under other agreements with third parties that
have been entered into prior to the date that said HFC Network(s) is added by
amendment to Exhibit C; and (iii) SEREN shall not be precluded from receiving
long haul IP backbone services from Qwest and Means pursuant to the terms of the
respective agreements between SEREN and said third parties entered into prior to
the date of signing this Master Agreement.

       3.2    I3S RIGHT OF FIRST REFUSAL. I3S shall have a right of first
refusal to provide broadband data services not defined as HSDS hereunder in the
event that SEREN decides to offer such services at a HFC Network covered by this
Agreement. In the event that SEREN does not select I3S to provide any such
broadband data services, but either provides them itself or from a third party,
then SEREN and I3S shall agree, in good faith, to establish a mutually
acceptable means of compensation for I3S to the extent that any such broadband
data services require the use of assets owned by I3S hereunder. The decision to
accept or reject any such proposal from I3S or the timing thereof, is totally
within the discretion of Seren.

       3.3    SEREN'S RIGHT OF FIRST REFUSAL. SEREN shall have the right to
receive broadband data services not defined as HSDS hereunder from I3S in the
event that I3S decides to offer such services at a HFC Network covered by this
Agreement on terms and conditions mutually acceptable to the Parties.

                                    ARTICLE 4
                               SEREN'S OBLIGATIONS

       4.1    GENERAL OBLIGATIONS. In consideration of the mutual agreements of
the parties contained herein, SEREN expressly covenants and agrees to do and
perform, or cause to be done and performed, the following:

       (i)    SEREN grants I3S an exclusive right to provide HSDS as more
particularly set forth in Exhibit B attached hereto and incorporated herein by
reference to the HFC Network; and

       (ii)   SEREN shall, at its own expense, provide and maintain the
equivalent of at least four (4) video channels worth of bandwidth, or as
mutually agreed to by the Parties from time to


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time, on the cable antennae distribution facilities (the "System") at the HFC
Network headend to provide the HSDS; and

       (iii)  SEREN shall, at its own expense, operate and maintain the video or
telecommunications headend to the specifications described in Exhibit B (the
"Specifications") sufficient to ensure that the HSDS are properly delivered over
the local loop; and shall assume the operating and capital cost of the
following:

                   o  Monthly recurring local loop costs to the HFC Network
                      headend;
                   o  Monthly recurring property maintenance (Lce, Router);
                   o  Monthly recurring IP headend maintenance;
                   o  Customer Service Representative platform;
                   o  Internet browser platform user license;
                   o  HFC Network property IP equipment (Lce, Router);
                   o  Non-recurring local loop transport costs;
                   o  Customer billing and collections;
                   o  Subscriber premise equipment installation and maintenance;
                   o  Tier 1 customer care and support; and
                   o  Co-location facilities and HSDS CMTS or xDSLAM, and
                      related equipment, at each HFC Network headend or
                      telecommunications central office

       (iv)   after the initial training by I3S as provided for herein, SEREN
shall pay the cost for training its own personnel to maintain the System up to
the Specifications; and

       (v)    SEREN shall maintain commercial general liability insurance with
minimum limits of not less than $1,000,000 per occurrence for bodily injury (or
death) and property damage liability with limits of at least $1,000,000 per
occurrence [Personal Injury and $1,000,000 General Policy Aggregate (applicable
to Commercial General Liability Policies)] which names I3S as an additional
insured; and

       (vi)   on behalf of I3S, SEREN shall secure access to all properties of
SEREN as necessary to provide the HSDS; and

       (vii)  the employees, agents, or contractors of I3S shall have reasonable
access, at no charge, to the HFC Network and facilities of SEREN in connection
with and to perform any and all work reasonably necessary to provide the HSDS at
the HFC Network, including, but not limited to, installation, inspection,
maintenance, repair or removal of equipment, or to facilitate the provision of
the HSDS to customers; and

       (viii) each party's employees, contractors, or agents will, while on the
premises of any other party, comply with all applicable law and regulations and
any reasonable written rules or regulations of SEREN applicable to all tradesmen
or contractors on the premises; and

       (ix)   all revenue sharing or other payments to SEREN for discharging its
obligations hereunder shall be as set forth herein. I3S shall have no other
obligation to pay any revenue


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shares, commissions, or other consideration to SEREN in connection with the
provision of HSDS; and

       (x)    any and all maintenance or other problems with respect to I3S'
obligations set forth in Exhibit B (HSDS Service Level Agreement) hereunder will
be reported directly to I3S to the point of contact designated in writing by I3S
(the "Contact") for resolution by I3S; and

       (xi)   SEREN will provide a secure air-conditioned space, at no charge,
to I3S for the storage of all equipment reasonably necessary to provide the HSDS
at the HFC Network Headend; and

       (xii)  SEREN will provide electricity necessary to power I3S co-located
equipment; and

       4.2    MARKETING. SEREN and I3S will consult and develop a joint
marketing strategy designed to co-brand and promote the HSDS hereunder.


                                    ARTICLE 5
                          AFFIRMATIVE COVENANTS OF I3S

       5.1    GENERAL OBLIGATIONS. In consideration of the mutual agreements of
the parties contained herein, I3S covenants and agrees to do and perform, or
cause to be done and performed, the following:

       (i)    I3S possesses and shall maintain for the term of this Agreement
any and all property, right, title or interest necessary to lawfully provide the
HSDS as contemplated in this Agreement, and all such property, right, title and
interest shall remain free and clear of any adverse claims, interests and liens.

       (ii)    I3S possesses and shall maintain in full force and effect for the
term of this Agreement, all material permits, licenses, franchise rights,
trademarks, trademark rights, trade names, trade name rights and copyrights
which are required to provide the HSDS.

       (iii)  With respect to performance hereunder, I3S agrees to maintain, at
all times during the term of this Agreement, as a minimum, commercial general
liability insurance with minimum limits of $1,000,000 per occurrence for bodily
injury (or death) and property damage liability with limits of at least
$1,000,000 per occurrence [Personal Injury and $1,000,000 General Policy
Aggregate (applicable to Commercial General Liability Policies)] and any
additional insurance and/or bonds required by law. Upon request, I3S agrees to
furnish certificates or other acceptable proof of the foregoing insurance and
name SEREN as an additional insured and also name such Owners and Operators as
an additional insured who may request it. I3S warrants that it meets or exceeds
all insurance requirements stated herein and those that are required by the laws
in the State of Texas.


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       (iv)   As more specifically described in Exhibit A (description of HSDS
provided by I3S) attached hereto and incorporated herein by reference, I3S
shall assume and pay all operating and capital costs and expenses associated
with any and all:

                   Monthly recurring private Internet exchange points;
                   Monthly recurring switch maintenance;
                   Monthly recurring POP transport;
                   Monthly recurring Dallas network operations center costs
                   (including installation costs);
                   Customer support IP technicians and engineers (NOC
                   personnel);
                   I3S-specific training, to include HSDS system launch at the
                   HFC Network and integration support, customer premise
                   equipment installation, marketing and sales training for
                   residential and commercial services, Tier 1 customer care and
                   support training, and operational procedural training for the
                   Services;
                   Insurance on I3S capital equipment;
                   I3S-specific travel and entertainment;
                   Switch site equipment (including installation costs);
                   Peering point routers;
                   Private Internet exchange point
                   hardware (including installation costs);
                   I3S network infrastructure equipment;
                   Transport facilities to the HFC Network Headend;
                   Backbone transport facilities;
                   IP master headend equipment; and
                   Tier 2 and 3 customer care and IP engineering support
                   IP Addresses

       (v)    I3S shall activate a metropolitan Point of Presence within sixty
(60) days of receipt of written notification from SEREN that it is prepared to
commence the delivery of HSDS at a HFC Network.

       (vi)   Seren shall have operational responsibility for a DS-3 circuit
between I3S' metropolitan Point of Presence in Minneapolis, Minnesota and
SEREN's HFC Network CATV head end in St. Cloud, Minnesota; provided, however,
that I3S shall assume, and SEREN shall no longer pay, the monthly recurring cost
of said DS-3 circuit on the first (1st) day of the immediately succeeding month
that at least 2,500 subscribers are receiving HSDS at the HFC Network for St.
Cloud, Minnesota.

       (vii)  I3S understands and agrees that the Subscribers of the HSDS are
Seren's customers. I3S agrees that, except as described in Article 3.1, during
the term of this Agreement and for a period of six months during the transition
upon termination period set forth in Section 12.5 hereof, it shall not attempt
to solicit Seren's customers for HSDS or other similar services within the HFC
Network franchise service territory.

       (viii) Provide Seren with specific PC hardware and software subscriber
requirements.

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                                    ARTICLE 6
                            DESCRIPTION OF THE HSDS

       6.1    DESCRIPTION OF THE HSDS. During the term of this Agreement, I3S
shall provide, or cause to be provided, to HFC Networks, the HSDS, more
particularly described and set forth in Exhibit A attached hereto and
incorporated herein by reference.


                                    ARTICLE 7
                  DEFINITION OF HSDS SERVICE LEVEL STANDARDS

       7.1    DEFINITION OF SERVICE LEVEL STANDARDS. Subject to the conditions,
qualifications and limitations set forth herein, during the term of this
Agreement, I3S shall use its commercially reasonable efforts to offer, or cause
to be offered, the HSDS level standards pertaining to various aspects of the
HSDS, as more particularly described and set forth in Exhibit B attached hereto
and incorporated herein by reference.


                                    ARTICLE 8
          REVENUE ALLOCATION; CUSTOMER ACCESS PRICING; BRANDING

       8.1    REVENUE ALLOCATION. With respect to HSDS utilizing HFC cable modem
technology to serve Seren's customers, monthly recurring Internet access revenue
received from HSDS Subscribers at HFC Networks (the "Revenue") will be paid
directly by customers to SEREN; provided, however, that, by the twenty-fifth day
of each calendar month hereafter SEREN shall pay I3S a share of the Revenue in
an amount equal to **** of the Revenue; provided, however, that in no event
shall said share of the Revenue be less than ** per Subscriber per month; and
further provided, however, that in no event shall said share of the Revenue be
less than (i) ** per month upon achieving the first 1000 prospective HSDS
subscribers at an HFC Network, (ii) ** per month upon achieving at least **
prospective HSDS subscribers at said HFC Network, and (iii) ** per month upon
achieving at least ** prospective HSDS subscribers at said HFC Network, and at
all times thereafter, for each municipal cable television headend.

         With respect to HSDS utilizing technology other than HFC cable modem
technology to serve Seren customers, monthly recurring Internet access revenue
received from Subscribers (the "Revenue") will be paid directly to SEREN;
provided, however, that, by the twenty-fifth day of each calendar month
hereafter SEREN shall pay I3S a share of the Revenue in an amount equal to ****
** of the Revenue; provided, however, that in no event shall said share of the
Revenue be less than ** per Subscriber per month.

         In addition to its ability to terminate as provided for in Article 12,
in the event that I3S fails to meet the SLA standards of Exhibit B, for any
given month, Seren shall be relieved from paying the monthly revenue minimums
identified above.


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       8.2    CUSTOMER ACCESS PRICING. With the intent to increase HSDS
penetration at each HFC Network, SEREN, in consultation with I3S shall establish
the price at which access to the HSDS is made available to subscribers.

       8.3    BRANDING. With respect to the HSDS, and the promotion thereof, I3S
and SEREN shall mutually establish the brand names, logos, labels, trademarks,
HSDS marks and other such identifying promotional characteristics pertaining to
the same throughout the term of this Agreement.

       8.4    RE-EVALUATION OF ECONOMIC TERMS. Thirty-six (36) months after the
Effective Date, and upon the expiration of each twenty-four (24) month period
thereafter, or in the event of any final regulatory or judicial proceedings,
changes or decisions affecting the HSDS at the HFC Network, the parties agree to
renegotiate the Revenue Allocation in good faith in accordance with current
market standards, such that the Revenue Allocation shall be increased or
decreased if either party is economically disadvantaged hereunder, or receiving
an inordinate proportion of the revenue associated with HSDS in relation to its
investment or contribution to the relationship established hereby.

         In addition, I3S agrees to decrease its percentage share of Revenue
by * for every * HSDS Subscribers that Seren achieves on an aggregate basis for
all of its HFC Networks, excluding the St. Cloud HFC Network. However, except as
provided for in this Section 8.4 above, in no event shall I3S receive less than
* Revenue Share as provided for herein.

       8.5    COMPED SERVICE. I3S understands and agrees that, upon advance
written notice to I3S, Seren shall have the ability to provide comped (i.e.
free) Internet access services to employees, primary and secondary schools,
libraries and local governmental facilities. No Revenue will be due I3S as a
result of such services being offered by Seren.

                                    ARTICLE 9
                          SPECIFIC SOFTWARE WARRANTIES

       9.1    OWNERSHIP; AUTHORITY. I3S represents and warrants that the
software utilized hereunder (collectively, the "Products") are free and clear of
all liens and encumbrances, and that it has full power, license 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 I3S the Products utilized hereunder will not infringe or
violate any copyright, trade secret, trademark, patent or other intellectual
property rights of any third party.

       9.2    SOFTWARE COMPATIBILITY. I3S will accommodate any subscriber
browser (e.g. Netscape, Explorer) or operating systems (Windows, NT, MAC, Unix).

       9.3    SEREN'S Y2K REQUIREMENTS. All computer systems and applications,
and all embedded computer components and devices maintain full functionality,
performance, and future maintainability, accurately process date/time data
(including but not limited to, calculating, comparing, sorting, and sequencing)
from, into, between, and throughout the twentieth and twenty-first centuries. In
addition to all other contract requirements, I3S agrees


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that the services and/or equipment provided to Seren under this agreement are
Year 2000 compliant. I3S agrees that its operations will be capable of
continuing an uninterrupted flow of goods and services into and through the year
2000. I3S agrees that the computing software and hardware, supplies, material,
or equipment ("Equipment") purchased, rented, leased or acquired for use by
Seren is compliant with Seren's "Year 2000 Requirements," (defined below) and
said Equipment shall not be accepted in part or whole by Seren unless
specifically disclosed and agreed to by Seren in writing.

                                   ARTICLE 10
                                 INDEMNIFICATION

       10.1   INTELLECTUAL PROPERTY RIGHTS INDEMNIFICATION. I3S shall defend,
indemnify and hold harmless SEREN, its 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, HSDS mark, copyright, patent or other
intellectual property rights (the "Intellectual Property Rights") in connection
with the use of said Intellectual Property Rights hereunder. I3S's obligation
pursuant to the immediately preceding sentence is subject to the following
conditions: (i) SEREN shall give I3S prompt written notice of all actions,
claims or threats against SEREN of infringement or violation of Intellectual
Property Rights; (ii) SEREN shall permit I3S to elect to assume complete control
of such claims at its sole discretion and expense; and (iii) SEREN shall
cooperate fully with I3S 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.  INDEMNIFICATION. Each party shall indemnify the other against all
liability, loss, damage, and expense resulting from injury to or death of any
person (including injury to or death of their employees) or loss of or damage to
tangible real or tangible personal property (including damage to their property)
or the environment, but only to the extent that such liability, loss, damage or
expense was proximately caused by its breach of this Agreement or by any
negligent act or omission, willful misconduct or violation of law on the part of
the party from whom indemnity is sought ("the Indemnitor"), its agents,
employees, subcontractors or assignees. Indemnitor shall have the right to
assume defense of the claim with counsel reasonably acceptable to Indemnitee.
Indemnitee shall be entitled to participate in the defense of the claim with its
own counsel at its sole expense.


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                                   ARTICLE 11
                        PROTECTION OF PROPRIETARY RIGHTS

       11.1   CONFIDENTIAL INFORMATION. Information to be held in confidence
shall be clearly marked "Proprietary" or "Confidential." Information which is
conveyed orally shall be deemed confidential only if prior to disclosure it is
indicated as being confidential and written confirmation identifying the
confidential or proprietary information is provided to the receiving party
within ten (10) business days after it was discussed orally.

       11.2   RESTRICTIONS. Each party shall use its reasonable 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 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. Unless approved in advance by the non-disclosing party, except
for the existence of this Agreement, the terms and provisions of this Agreement
shall remain strictly confidential and shall not be disclosed to any third party
other than a party's attorneys, accountants and other professional advisers.

       11.3   AUTHORIZED DISCLOSURES. Notwithstanding the obligations described
in Section 11.2 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; 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 bona-fide 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 11 shall survive the termination of this Agreement for two (2) years
thereafter.

       11.6   CONFIDENTIALITY OF TERMS. Unless approved in advance by the
non-disclosing party, except for the existence of this Agreement, the terms and
provisions of this Agreement shall remain strictly confidential and shall not be
disclosed to any third party other than a party's attorneys, accountants and
other professional advisers.


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       11.7   SEREN SUBSCRIBERS. Without the prior written consent of
Seren, I3S will not disclose information about Seren customers who are being
offered HSDS or who have subscribed to HSDS. In addition, I3S will not market
any other services to Seren customers without giving Seren prior notification.
I3S shall not reveal the name or addresses of Seren customers to any third party
except as necessary to fulfill its obligation to provide the HSDS. I3S shall not
permit any third party to use the Seren customer names for any purpose unrelated
to this Agreement.

                                   ARTICLE 12
                              DEFAULT; TERMINATION

       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 misrepresentation by the defaulting
party;

  (b) Material failure to perform the defaulting party's obligations hereunder,
including with respect to I3S its failure to maintain the HSDS standards set
forth in Section 7.1 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 within thirty (30) days, except for defaults
pursuant to Section 12.1(c) which shall have a cure period of ninety (90) days,
after written notice of such default by the non-defaulting party specifying the
acts or omissions constituting the default with reference to the sections of
this Agreement which have allegedly been breached, 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. Termination of this Agreement shall not
impair either party's then accrued rights, obligations, liabilities or remedies
hereunder.


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       12.5   TRANSITION UPON TERMINATION. Notwithstanding the termination
of this Agreement, I3S shall maintain its facilities and continue to provide the
HSDS to the HFC Networks for a reasonable period of time (not to exceed six (6)
months from the date of termination) until SEREN has made arrangements with
another Internet service provider, and I3S shall cooperate with SEREN in an
orderly and efficient transition of the Subscribers to any other Internet
service provider designated by SEREN.

                                   ARTICLE 13
                           NOTICE; PUBLIC DISCLOSURES

       13.1   NOTICE. All notices pursuant to this Agreement shall be in writing
and may be personally delivered or sent by overnight courier or by Certified or
Registered mail. All notices personally delivered shall be deemed delivered at
the time of such delivery. All notices sent by Certified or Registered mail
shall be deemed delivered five (5) days after deposited in the US mail. All
notices sent by overnight courier shall be deemed made one (1) business day
after delivery to such courier HSDS. Any party may designate a change of address
upon ten (10) days written notice.

                                       If to I(3)S, to:
                                       I(3)S, Inc.
                                       1440 Corporate Drive
                                       Irving Texas 75038
                                       Attn: Mr. Jim Price, CEO

                   with a copy to:
                                       I(3)S, Inc.
                                       1440 Corporate Drive
                                       Irving Texas 75038
                                       Attn: Matt Hutchins, President


                                       If to SEREN, to:
                                       SEREN Innovations, Inc.
                                       15 South 5th Street, Suite 500
                                       Minneapolis, MN 55402
                                       Attn: President

       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
                               DISPUTE RESOLUTION

         In the event a dispute arise between SEREN and I3S, or the successors
or assigns of either of them, regarding this Master Agreement or any particular
HFC Network Agreement, the


                                       12
<PAGE>   13

aggrieved party shall promptly notify the other Party of its intent to invoke
this dispute resolution procedure after such dispute arises. If the Parties
shall have failed to resolve the dispute within ten (10) days after delivery of
such notice, each Party shall, within five (5) days thereafter nominate a senior
officer of its management to meet at any mutually agreed location to resolve the
dispute. Should the Parties be unable to resolve the dispute to their mutual
satisfaction within ten (10) days after such nomination, such dispute shall be
settled by arbitration.

         The Party desiring arbitration shall give notice to the other Party in
writing specifying the question or questions to be settled and at the same time
naming an arbitrator. The Party receiving such notice shall within ten (10) days
thereafter give to the other Party a like written notice giving the name of an
arbitrator chosen by it and specifying any additional matter on which an award
is desired. If the Party receiving notice of arbitration fails to name an
arbitrator within ten (10) days, then the second arbitrator shall be appointed
by the American Arbitration Association. Only Parties qualified as specialists
in the matter in controversy will be appointed as arbitrators. The third
arbitrator shall, within ten (10) days of the appointment of the second
arbitrator, be selected by the two arbitrators theretofore appointed. If
arbitrators shall have been appointed by the respective parties and shall have
failed to select the third arbitrator, within the time provided herein, the
third arbitrator shall upon application of either of the parties to the
arbitration, be appointed by the American Arbitration Association within ten
(10) days after receipt of a Party's application to appoint a third arbitrator.
The arbitrators shall proceed immediately to hear and determine the matter in
controversy. Each Party shall be entitled to produce witnesses and appear in
person and by counsel before said arbitrators, but the number of witnesses to be
heard, the length of argument, the time consumed in such hearing, and the
general conduct of the proceedings shall conform to the rules promulgated by the
American Arbitration Association. The arbitrators shall be limited to accepting
the position contended for by either I3S or Seren, without modification, in
making their award. The arbitrators shall be instructed that their awards must
be made within forty-five (45) days of the appointment of the third arbitrator,
subject to any reasonable delay due to unforeseen circumstances. The award of
the arbitrators shall be drawn up in writing and signed by the arbitrators, or a
majority of them, and shall be final and binding on the Parties, and the Parties
shall abide by the award and perform the terms and conditions thereof. The award
of the arbitrators shall be made retroactive to the date the first Party
notified the other Party of its intent to invoke the dispute resolution
procedure. Unless otherwise determined by the arbitrators, the fees and expenses
of the arbitrator named by I3S shall be paid by I3S, the fees and expenses of
the arbitrator named by Seren shall be paid by Seren and the fees and expenses
of the third arbitrator shall be paid in equal proportions by the Seren and I3S.
Save as herein otherwise expressly provided, the rules of the American
Arbitration Association shall apply; provided, however, that wherever and
whenever there is conflict between the provisions of this Article and the
provisions of the said rules, the provisions of this Article shall apply.

         Notwithstanding any other remedies, and in the event that either Party
brings legal action upon the other Party for failing to perform any of its
obligations or failing to act in accordance with the provisions of this
Agreement, the Party which prevails in such legal action shall be entitled to
recover all reasonable legal fees incurred with regard to the legal action from
the other Party.


                                       13
<PAGE>   14


         I3S is obligated to continue providing HSDS as provided for herein
during the pendency of any dispute.

                                   ARTICLE 15
                                  MISCELLANEOUS

       15.1   ENTIRE AGREEMENT. This Master Agreement, together with the
schedules, attachments and exhibits attached hereto or referred to herein,
constitutes the entire Agreement and understanding among the parties hereto with
respect to the provision of the HSDS at the HFC Networks and is the final
expression of their Agreement on that subject 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.

       15.2   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.

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

       15.4   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.

       15.5   GOVERNING LAW. This Agreement, and any claims, counterclaims and
cross suits, shall be governed by and construed in accordance with the local
laws of the state in which the defendant or non-enforcing party resides, without
regard to conflicts of law principles. Each party hereby irrevocably submits to
the jurisdiction of the state or federal courts of the state in which the
defendant or non-enforcing party resides for the resolution of disputes
hereunder.

       15.6   CONTINUITY OF CONTRACT. 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.

       15.7   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
<PAGE>   15


       15.8   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.

       15.9   HIRING PROHIBITED. 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.

       15.10  PERFORMANCE REVIEW. In the event of any dispute or controversy
between the parties of any kind or nature, except in circumstances where
equitable relief is deemed necessary by either party in its sole discretion,
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 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.

       15.11  BINDING NATURE; ASSIGNMENT. 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.

       15.12  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. I3S has the sole
right to supervise, manage, contract, direct, procure, perform or cause to be
performed the day-to-day work to be performed by I3S under this Agreement unless
otherwise expressly provided herein or agreed to by the parties in writing.

       15.13  COUNTERPARTS. This Agreement may be signed in counterparts with
the same effect as if the signature on each counterpart were upon the same
instrument.

       15.14  SEVERABILITY. The Parties agree that multiple HFC Networks may
become subject to this Agreement. Any default or termination (whether voluntary
or involuntary) by any party with respect to a particular HFC Network shall
operate as a default or termination only


                                       15
<PAGE>   16

with respect to the parties' responsibilities and obligations as they relate to
the specific HFC Network or HFC Networks, as the case may be. Unless otherwise
agreed to by the parties with respect to the particular default, a default shall
be construed, where possible, to exclude unaffected HFC Networks.

       15.15  COMPLIANCE WITH APPLICABLE LAWS. I3S represents and warrants that
the provision of the HSDS pursuant to this Agreement shall be in compliance with
all applicable federal and state laws, rules and regulations.

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



I(3)S, INC.                        SEREN INNOVATIONS, INC.


By: /s/ MATTHEW HUTCHINS           By:   /s/ GLYNIS HIRSCHBERGER
   --------------------------         --------------------------------
   Matthew Hutchins                Printed Name: Glynis Hirschberger
   President                                    ----------------------
                                   Title: President and CEO
                                         -----------------------------

Date:  6/22/99                     Date:    6/21/99
     ------------------------           ------------------------------


                                       16
<PAGE>   17

                                LIST OF EXHIBITS




 EXHIBIT A: Description of the High Speed Data Services Provided by I3S

 EXHIBIT B: HSDS Service Level Agreement

 EXHIBIT C: HFC Network List


                                       17
<PAGE>   18

                                    EXHIBIT A

             DESCRIPTION OF HIGH SPEED DATA SERVICES PROVIDED BY I3S


The I3S HSDS is a data network that provides transport and peering functions of
Internet Protocol (IP) data traffic, including, without limitation:

o  Broadband access networks at the HFC Network composed of one or more
   broadband access technologies including but not limited to coaxial or hybrid
   fiber coaxial (HFC) cable television distribution systems, twisted-pair
   copper-wire-based telephone distribution systems, twisted-pair
   copper-wire-based local area network distribution systems and
   fiber-optic-based local area network distribution systems;

o  Local loop networks that connects the broadband access networks on each HFC
   Network to the I3S regional points-of-presence (POPs) in each metropolitan
   area served by I3S;

o  Regional point-of-presence networks that connects the POPs to the i3s.net
   national IP backbone;

o  A national IP backbone consisting of broadband communication facilities for
   the transport of data among I3S POPs and public and private Exchange Points
   where data and Internet routing information will be exchanged with other
   networks peered with i3s.net as part of the global Internet;

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 or
                more newsgroups;
      o         Internet World Wide Web (HTTP) services;
      o         Internet chat (IRC and MIRC);
      o         Conferencing and collaboration bridges;
      o         Streaming multimedia services such as Microsoft's NetShow and
                Progressive Network's RealMedia;
      o         A branded suite of client software that include:
      o         Web browser;
      o         Mail reader;
      o         News reader;
      o         Chat client;


                                       1
<PAGE>   19
      o         Chat client;

      o         Conferencing and collaboration client;

      o         Appropriate plug-ins and ActiveX controls.

o  Certain customer HSDS functions that include:

      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 I3S;

      o         Aggregated content created by others but licensed by I3S and
                improved for uses in a HSDS System;

      o         Aggregated content created by others but licensed by I3S and
                used unimproved.


                                       2
<PAGE>   20
                                  REQUIREMENTS
                      RELATED TO BROADBAND ACCESS NETWORKS
             UTILIZING MULTIPLE BROADBAND ACCESS TECHNOLOGIES (mBAT)


SEREN'S RESPONSIBILITIES

         Provide, or cause to be provided, as mutually agreed between the
         parties, suitable physical-layer coaxial-cable, twisted-pair
         copper-wire, or fiber-optic distribution plant on each SEREN property
         that will meet or exceed I3S specifications;

         Maintain, or cause to be maintained, physical layer distribution plants
         built and owned by SEREN that are used for I3S's HSDS;

         Install, maintain and operate data delivery equipment for each HSDS HFC
         Network. Installation and maintenance will meet or exceed
         manufacturer's specifications and the requirements set forth in the
         Agreement. Through itself or its agents, SEREN will assist I3S with
         pre-installation engineering planning and HFC Network site survey
         questionnaires;

         Assume the cost of the acquisition of all data communication equipment
         necessary to provide HSDS and to provide termination and delivery of
         HSDS between the Subscriber and the I3S POP in each Market;

I3S RESPONSIBILITIES:

         Provide technical specifications for suitable physical-layer
         distribution plants for I3S's HSDS;

         Inspect and accept or reject, according to the mutually agreed
         specifications, physical-layer distribution plants proposed by SEREN as
         suitable for 13S's HSDS;

         Integrate all data delivery equipment for each HFC Network into the I3S
         Element Management System portion of its Network Management Platform
         using SNMP and/or RMON. I3S will monitor all data delivery equipment
         twenty-four hours per day, seven day per week (24x7);

         Without limitation on the foregoing or the attached SLA, 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;

         Provide HSDS transport through the POP to Headend, except as noted
         herein.


                                       3
<PAGE>   21

                             ADDITIONAL REQUIREMENTS
                      RELATED TO BROADBAND ACCESS NETWORKS
                 UTILIZING CABLE TELEVISION DISTRIBUTION SYSTEMS


SEREN'S RESPONSIBILITIES (THESE RESPONSIBILITIES SPECIFICALLY APPLY TO THE
EXTENT HSDS IS TO BE PROVIDED BY I3S BY MEANS OF AN INTERCONNECTION TO SEREN'S
CATV DISTRIBUTION PLANT AT EACH HFC NETWORK. SEREN SHALL USE ALL COMMERCIALLY
REASONABLE EFFORTS TO PERFORM THESE RESPONSIBILITIES.):

    Cause CATV infrastructure to comply with FCC requirements;

    Upgrade, or cause to be upgraded, property CATV infrastructure to provide
    bi-directional cable delivery to all subscribers;

    Cause the upgraded bi-directional CATV infrastructure to exceed the minimal
    operational requirements of the I3S cable modem system, which are:

<TABLE>
<CAPTION>
----------------------------------------------------------------------------------------------------
           MINIMUM CABLE TELEVISION NETWORK                                VALUE
             REQUIREMENTS 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, four (4) six MHz (or as mutually agreed to by
the Parties from time to time) video channels within the CATV infrastructure
bandwidth on Internet served properties; two (2) in the spectrum from 54 MHz to
750 MHz and two (2) in the

                                       4
<PAGE>   22

    5MHz to 50 MHz spectrum; and reserve additional video channels, in the same
    spectrums for future expansion as Subscriber penetration at the HFC Network
    increases; and


    Designate, or cause to be designated, an engineering point of contact for
    each cable company operating the cable television distribution system for
    I3S Network Operations Center (NOC) to report problems or failures related
    to the cable television distribution system twenty-four hours per day, seven
    days per week (24x7).

I3S RESPONSIBILITIES:

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

        Within (15) fifteen minutes of notice, report to SEREN's designated
        engineering point of contact any problems observed by the I3S NOC in the
        course of operating the cable modem system network management features;
        and

        Within (15) fifteen minutes of notice, report to SEREN's designated
        engineering point of contact any problems determined by Subscriber
        contact in the course of operating the Subscriber Help Desk.

        I3S to provide NOC connections and services to monitor end to end
        network connections.


                                       5
<PAGE>   23

                           LOCAL LOOP CHARACTERISTICS

SEREN'S RESPONSIBILITIES

     Provide, or cause to be provided, proper space, security and power for
     Local Loop termination and transmission equipment necessary to provide
     Internet delivery and other data services at each HFC Network.

     Order, provision, install and maintain local loop communications links
     between each HFC Network and I3S POP in each Market with a bandwidth as
     mutually agreed to by the Parties.

I3S RESPONSIBILITIES:

     Install, maintain and operate local loop termination and transmission
     equipment necessary for each property offering HSDS. Installation and
     maintenance will meet or exceed manufacturer's specifications and the
     requirements set forth in the Agreement. Through itself or its agents,
     SEREN will assist I3S with pre-installation engineering planning and site
     survey questionnaires;

     Integrate all local loop termination and transmission equipment for each
     HFC Network into the I3S Element Management System portion of its Network
     Management Platform using SNMP and/or RMON. I3S will monitor all local loop
     termination and transmission equipment twenty-four hours per day, seven day
     per week (24x7);

     Assume the cost of the acquisition of all local loop termination and
     transmission equipment necessary to provide HSDS and to provide termination
     and delivery of HSDS between the Property and the I3S POP in each Market;

     Without limitation on the foregoing or the attached SLA, 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; and

     Configure and operate all local loop termination and transmission equipment
     to efficiently integrate with the rest of the I3S.net network.


                                       6
<PAGE>   24

                                POINT OF PRESENCE
                    FEATURES AND ESTABLISHMENT REQUIREMENTS

I3S RESPONSIBILITIES:

     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;

     I3S 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, I3S 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; and

     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,
     provided however, I3S is not guaranteeing bandwidth throughput from its POP
     to subscribers.

                                       7
<PAGE>   25

                           I3S INFORMATION OPERATIONS
             CONTENT PRODUCTION; SEREN/BROADBAND NOW!(TM) LAUNCH PAGE

I3S operates, and shall operate for the term of this Agreement, an information
content operation for creating original content or aggregating content created
by others and licensed to I3S for inclusion in the I3S body of content. This
material will consist of but not limited to informational, educational,
recreational, entertainment and business content. This body of content will be
offered to Subscribers of the HSDS product.

Without limitation on paragraph 1 above, I3S will create content as creative
and/or business opportunities present themselves. The I3S content will be
updated as I3S, using its editorial judgment, sees fit, but in no event less
frequently than good industry practice.

Certain portions of this content will be offered to all Subscribers free of
charge (Basic Content). Other portions of the content may be offered to
Subscribers on an optional fee basis for unlimited access to a fixed package of
content (Premium Content). Another certain portion of the content may be offered
to Subscribers on an optional fee basis for access to a specific time-limited
event (Pay-Per-View Content).

In addition to the fees charged customers for content, I3S may solicit and sell
national advertising and other revenue-producing transaction opportunities that
will appear on certain portions of the content.

All fees for premium content, pay-per-view content, national advertising and
revenue-producing transactions shall be determined solely by I3S.

The potential revenue set forth here for content shall not be subject to other
provisions in the Agreement (including attachments) regarding revenue sharing,
fees and pricing.

I3S, or its content partners, will design, produce and update, as necessary, all
content and be responsible for all such costs.

I3S shall initially design, produce and update, as necessary, a customized
launch page (the "Launch Page") for Subscribers, which can be used to market and
promote the HSDS, and, on I3S's standard time and materials rates (or as
otherwise agreed by the parties), SEREN's other SERVICES. In addition, the
Launch Page will include hyperlinks to SEREN's corporate web sites as directed
by SEREN. The Launch Page shall meet the technical, functional and appearance
requirements specified by I3S. I3S shall from time to time update the Launch
Page throughout the Term in accordance with the terms of this Agreement. I3S may
offer Subscribers Launch Pages that are personalized (by property) and that, in
addition to the features described above, may promote the I3S content offerings
and provide direct hyperlinks to the I3S content.

In no event, at any time during the term of this Agreement, shall I3S knowingly
permit or use any (i) content in the SEREN/Broadband Now! web site or within its
information content operations which contains obscene material, sexually
explicit adult programming, or indecent material as defined in Section 47
C.F.R.76.701(g); (ii) material in the SEREN Broadband

                                       8
<PAGE>   26

Now! web site soliciting or promoting unlawful conduct; or (iii)
programming in the SEREN/Broadband Now! web site that may or could have been
subject to the Telecommunications Act of 1996, Section 641, relating to the
scrambling of sexually explicit adult video HSDS programming.

CONTENT PUBLISHING PLATFORM


       o  I(3)S will provide SEREN access to its automated publishing system for
          the purposes of SEREN publishing localized content in each of its
          geographic markets into the SEREN/BroadbandNOW! information service.
       o  SEREN's local content will be contained within the brand and Internet
          domain of BroadbandNOW!
       o  SEREN will provide the editorial and advertising content and be
          responsible for the costs of its creation.
       o  SEREN will sell advertising that may be associated with the local
          content it creates and keep any resulting revenue.
       o  I(3)S will provide a Web-based and/or email-based interface for
          SEREN's personnel to enter editorial content into the I3S publishing
          system.
       o  I(3)S will provide a workflow process for SEREN to manage and approve
          the publication of editorial content.
       o  I(3)S will provide the use of its standard publishing templates for
          publishing SEREN's local content in the BroadbandNOW! pages.
          Development of specialized or non-standard publishing templates
          requested by SEREN will be at SEREN's expense.



I(3)S CONTENT PHILOSOPHY

       o  Internet access is always an "open" experience.
       o  Customers spend time on our network only when it offers a high degree
          of value.
       o  They use our content and services because they want to, not because
          they have to.
       o  We develop content and services that take advantage of the unique
          value of the broadband experience rather than trying to rebuild or
          replace those services our customers already use and enjoy.

                          CONTENT DEVELOPMENT STRATEGY

       o  Bring the best content and services onto our network.
       o  Focus on a new class of services that are broadband specific or that
          are greatly enhanced by broadband.
       o  Develop original content and a new interface designed specifically for
          this medium and this audience, delivering a coherent whole.

STRATEGY: THE BEST OF THE NET

       There are some "basics" users expect:

              1. Search


                                       9
<PAGE>   27

              2. News

              3. Weather

              4. Stock Quotes, etc.

       Rather than rebuilding these functions, we enhance the experience of
using them.

                        STRATEGY: A NEW CLASS OF SERVICES

       o  There is an emerging new category of services that are broadband only
          or that are greatly enhanced by broadband.

       o  High-bandwidth content and services that were only theorized before
          can be delivered now.

       o  I(3)S is investing in the infrastructure to bring these services
          on-network and to integrate them highly with the rest of our offering.

 Strategy:  Built for Broadband

       o  I(3)S has developed an original platform and leading edge interface
          designed for broadband that brings it all together.

       o  And developed a new class of content, built from the ground up
          specifically for our broadband audience.

 Timeline:  Version 2.0 - March 1999

       o  Sections expanded from four to seven, establishing a platform for more
          original and aggregated content
       o  Greatly expanded localization
       o  Broadcast.com integration
       o  Backup service
       o  Portal partner
       o  Expanded help and customer account management and services

                          TIMELINE: VERSION 3.0 - Q3/Q4

       o  CD-ROM library online
       o  Other Targets/Goals:

              1. Online Gaming
              2. Expanded audio and video library
              3. Web-based email

       o  With greater depth comes a higher degree of personalization

                                       10
<PAGE>   28


                     LOCALIZATION: LEVEL 1 -- NATIONAL VIEW

       o   Smaller markets get a national view with access to most or all
           services not specifically tailored to their local market

       o   This is where the competition stops!

       Localization: Level 2 -- Localized View

       o   In larger markets, all services are customized to the local area:

                 1.   Local news, weather, sports, links, etc.
                 2.   Localized libraries of aggregated video, audio, multimedia
                      content

                  LOCALIZATION: LEVEL 3 -- ORIGINAL DEVELOPMENT

       o   Markets with large populations, or markets of strategic importance
           also get:

                 1.   Original, exclusive, local content developed specifically
                      for broadband and specifically for the local market
                      through two methods:

                 2.   Local I3S teams develop content

                 3.   Local partners develop content exclusively for I(3)S

       o   Seren shall be entitled to create, author, promote and otherwise
           engage in the business related to local content offerings. Within the
           Seren/BBnow Homepage, Seren shall be allocated the local area as
           mutually agreed to be the Parties. Seren shall be entitled to solicit
           and insert advertising and other revenue producing transactions on
           local content for its own account in such allocated local area of the
           homepage. I3S agrees to facilitate the ability of Seren to create,
           update and insert both the local content and advertising originated
           by Seren.

       o   Seren and I3S will form an Editorial Board to ensure continuity
           between the Local and National content pages.


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                        CUSTOMER ADVOCACY CENTER FEATURES

I3S RESPONSIBILITIES

       Provide a toll free number for:


              Initial technical support inquires
              Technical support for all HSDS issues
              Technical support for Subscriber CPE issues related to HSDS

       Answer toll free line consistent with the SEREN/I3S HSDS co-brand.

       Operate 24x7 customer care call center operation.

       Maintain sufficient customer services staff and call center capacity to
       connect to Subscribers within 1 minutes of call entering processing
       operation.

       Develop and publish escalation procedure for Customer HSDS
       Representatives related to network issues.

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


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


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<PAGE>   30

                 SUBSCRIBERS' HARDWARE AND SOFTWARE INSTALLATION
                  SPECIFICATIONS AND INSTALLATION REQUIREMENTS

SEREN SHALL:

       Verify that potential Subscribers' personal computers meet the
       I3S-established minimum requirements for the supplied software and the
       HSDS;

       Make an appointment with each new Subscriber to meet the installation
       personnel for the installation of the HSDS in the Subscriber's unit;

       Collect the Subscriber information required to install, provision and
       complete the set up of Subscribers' HSDS. Seren and I3S will 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 Seren-supplied CPE and the I3S HSD;

       Verify, or cause to be verified, and if necessary, promptly (but not more
       than a reasonable time frame set by SEREN) perform repairs such that all
       access network services function properly (and to not less than the
       standards pre-existing I3S HSDS operations) after I3S completes
       installation and throughout the provision of HSDS;

       Maintain a sufficient inventory of CPE for each Market and develop
       procedures to restock CPE as used in Subscriber installations;

       Issue and install the required CPE for the HSDS requested by the
       Subscriber;

       Meet the Subscriber at the Subscribers location at the scheduled time
       within the tolerances and limits as defined in the I3S HSDS Service Level
       Agreement;

       Install the required cable modems(s) and have HSDS operational in the
       Subscriber's unit within the number of days of a Subscriber's request set
       forth in Section 6.4 of the Agreement;

       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 HSDS to be performed at
       the time of installation. This introduction will include how to launch
       the HSDS, 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;


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<PAGE>   31

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

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



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<PAGE>   32

                                    EXHIBIT B
                          HSDS SERVICE LEVEL AGREEMENT

This HSDS Level Agreement is attached and made a part of the Master High Speed
Data Services Right of Access and Marketing Agreement by and between I3S, Inc.
and Seren Innovations, Inc. (the "Agreement"). I3S shall use all commercially
reasonable efforts to perform these responsibilities.

INTRODUCTION

This Exhibit entitled "HSDS Level Agreement" ("SLA") sets out operation
specifications and requirements for HSDS provided by I3S for the residents or
customers of applicable SEREN HFC Networks. The SLA shall encompass data
SERVICES originating and terminating within the I3S internetwork ("i3s.net").

The HSDS provided by I3S 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 I3S, originating within end users' customer
premises and terminating within I3S 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 I3S provided SERVICES (or resold SERVICES) and the Equipment and
I3S-maintained facilities, but shall exclude customer error, defects in Customer
Premises Equipment ("CPE"), defects in customers' computers, defects in property
cable or wiring plants, defects in fiber optic distribution systems, defects in
cable television distribution systems and network problems experienced by
destination networks at or beyond Internet Exchange Points.

The terms and conditions of this SLA do not limit I3S's obligations set forth
elsewhere in the Agreement, but if there is a conflict with respect to HSDS
obligations between this SLA and the Agreement, this SLA shall control.

PERFORMANCE REQUIREMENTS

PERCENT CUSTOMER HSDS ORDER BEGINNING COMMITMENT DATES TIMELY MET

       Except for self-installs, I3S will provide final Remote Provisioning of
Modem within one hour of notification by Seren.

PERCENT CUSTOMER HSDS ORDER COMPLETION COMMITMENT DATES TIMELY MET

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


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<PAGE>   33

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

       I3S shall exhibit greater than 90% Customer HSDS Order Completion
       Commitment Dates Timely Met per month.

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 I3S 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 upon 72 hours advance
       notification by I3S, 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 access distribution plant (operated by SEREN or
       its designated third party operator) exceed the operational standards set
       by I3S for each type of Broadband access technology.

       I3S shall exhibit greater than 99.8% Network Availability per month.

       I3S to provide latency no greater than 120MS.

       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, provided however, I3S is not guaranteeing bandwidth throughput from
       its POP to subscribers.

PERCENT TIER 2 CUSTOMER CALLS ANSWERED WITHIN 45 SECONDS BY I3S 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 I3S National Customer Care Center and
       thereafter to be answered by a human customer representative within 30
       seconds. At a minimum, the I3S National Customer Care Center


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<PAGE>   34

       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 Customer Care Center calls
       answered in each calendar month and multiplying by 100.

       I3S 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 I3S at the I3S 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.

       o     For Trouble Reports received by I3S at the I3S 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.

       I3S 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 I3S alone.


       I3S shall exhibit greater than 90% Customer Repair Commitment Met per
       month.

REPORTS

       I3S shall provide to SEREN 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:

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

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


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<PAGE>   35

       Aggregate I3S National Customer Care Center data depicting the
       distribution of call waiting time in general and the percent calls
       answered and calls abandoned respectively.


HOLIDAYS


       New Years Day
       Memorial Day
       Independence Day
       Labor Day
       Thanksgiving
       Day after Thanksgiving
       Christmas



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<PAGE>   36

                                    EXHIBIT C

                               HFC NETWORK LISTING

1.     Seren's HFC Network serving St. Cloud, Minnesota and related service
       areas.

2.     Seren's HFC Network serving Contra Costa County, California.


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