EXHIBIT 10.1


                    JOINT MARKETING AND SERVICES AGREEMENT


      This JOINT MARKETING AND SERVICES AGREEMENT (this "Agreement") is made
and entered into as of the 22nd day of July 1997 (the "Effective Date"), by and
between IXC Internet Services, Inc., a Delaware corporation ("IXC"), and PSINet
Inc., a New York corporation ("PSINet").

      WHEREAS, IXC and PSINet have entered into an IRU and Stock Purchase
Agreement of even date herewith (the "IRU Agreement"), pursuant to which IXC
will provide to PSINet the right to use certain fibers and capacity on IXC's
fiber optic telecommunications system and PSINet will exchange therefor shares
of its stock;

      WHEREAS, PSINet is in the business of providing, on a dial and dedicated
basis to wholesale and end user customers, Internet connectivity and related
services;

      WHEREAS, IXC desires to create and market various service offerings to
customers incorporating or consisting entirely of an Internet services
component; and

      WHEREAS, PSINet is willing to provide such Internet services, and IXC is
willing to purchase such Internet services, on the terms and subject to the
conditions of this Agreement.

      NOW, THEREFORE, in consideration of the premises and the mutual covenants
of this Agreement, the Parties agree as follows:

1.          DEFINITIONS.

            For purposes of this Agreement, certain terms have been defined
below and elsewhere in this Agreement (including the attached Schedules) to
encompass meanings that may differ from, or be in addition to, the normal
connotation of the defined word. Unless the context clearly indicates
otherwise, any term defined or used in the singular shall include the plural. A
defined word intended to convey its special meaning is capitalized when used.

      "AFFILIATE" has the meaning set forth in Section 19.1 of the IRU
Agreement.

      "AGREEMENT" has the meaning set forth in the preamble.

      *

      "CLAIM" means any pending or threatened claim, action, proceeding or suit
by any Third Party.

      "CONFIDENTIAL INFORMATION" has the meaning set forth in Section 10.1.

      "CURE PERIOD" has the meaning set forth in Section 9.2.1.

      "DAMAGES" means any loss, debt, liability, damage, obligation, claim,
demand, judgment or settlement of any nature or kind, known or unknown,
liquidated or unliquidated, including without limitation all reasonable costs
and expenses incurred (legal, accounting or otherwise).




*     Confidential material has  been omitted and filed separately with the
      Securities and Exchange Commission





<PAGE>
      "DOCUMENTATION" shall mean Reseller Documentation and End User
Documentation.

      "EFFECTIVE DATE" has the meaning set forth in the preamble.

      "END USER DOCUMENTATION" shall mean all documentation provided by PSINet
for use by end users of its services in connection with the use and operation
of the materials describing such services, as such documentation may be
amended, modified or supplemented from time to time.

      "INDEMNIFYING PARTY" has the meaning set forth in Section 13.1.

      "INFRASTRUCTURE" has the meaning set forth in Section 6.1.

      "INTELLECTUAL PROPERTY RIGHTS" shall mean all intangible property rights
protectible by law throughout the world including all copyrights (including,
without limitation, the exclusive right to reproduce, distribute copies of,
display and perform the copyrighted work and to prepare derivative works),
copyright registrations and applications, trademark rights (including trade
dress), trademark registrations and applications, service mark rights, service
mark registrations and applications, patent rights (including the right to
apply therefor), patent applications therefor (including the right to claim
priority under applicable international conventions) and all patents issuing
thereon, and inventions, whether or not patentable, together with all utility
and design, know-how, specifications, trade names, mask-work rights, trade
secrets, moral right, author's rights, algorithms, rights in packaging,
goodwill and other intangible property rights, as may exist now and/or
hereafter come into existence, and all renewals and extensions thereof,
regardless of whether any of such rights arise under the laws of the United
States or of any other state, country or jurisdiction.

      "INTERNET" has the meaning set forth in Section 19.1 of the IRU
Agreement.

      "IRU AGREEMENT" has the meaning set forth in the recitals of this
Agreement.

      "IXC" has the meaning set forth in the preamble.

      "IXC CUSTOMER" means any purchaser of a service offering that includes
Services provided by PSINet under this Agreement. As used in this Agreement, an
"IXC Customer" shall include (i) any party with which IXC enters into an
agreement relating to the sale of services that include Services, (ii) any
party that purchases Services for which billing is provided by IXC, (iii) any
party that purchases Value-Added Services from IXC pursuant to Section 5.1.1,
and (iv) any purchaser of services that include Services from an IXC Reseller.
In cases where IXC uses Services provided by PSINet under this Agreement for
its own internal purposes, IXC shall be deemed an "IXC Customer" for purposes
of this Agreement.

      "IXC CUSTOMER INFORMATION" shall mean all information relating to each
IXC Customer collected in connection with the provision of Services to such IXC
Customer, including without limitation the name, address, usage, features and
services purchased, locations served, payment history and all other information
identifiable to a particular customer.

      "IXC DOCUMENTS" has the meaning set forth in Section 5.1.4.

      "IXC INTERNET SERVICES" means those Services offered by IXC to IXC
Customers.

      "IXC RESELLERS" has the meaning set forth in Section 5.1.1.





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<PAGE>
      "IXC SALES SUPPORT GROUP" has the meaning set forth in Section 3.2.

      "MANAGED CONNECTIVITY SERVICES" or "MCS" has the meaning set forth in
Section 2.1.1.

      "MARKS" shall mean trade names, logos, trademarks, trade devices, trade
dress, service marks, symbols, abbreviations or registered marks, or
contractions or simulations thereof, or any other indicia or origin.

      "MATERIAL PROVISION" shall mean any provision of this Agreement
(including, without limitation, payment provisions) the breach of which by one
Party is determined by an arbitration pursuant to Section 15.18 to constitute a
material adverse effect on the use and enjoyment by the other Party of the
benefits of this Agreement.

      "MULTIPLE END-USER RESTRICTIONS" has the meaning set forth in Section
5.1.2.

      "OPPORTUNITY CONSULTING SERVICES" or "OCS" has the meaning set forth in
Section 2.1.3.

      "PARTY" means IXC, individually, or PSINet, individually.

      "PARTIES" means IXC and PSINet, collectively.

      "PERSON" has the meaning set forth in Section 19.1 of the IRU Agreement.

      "PSINET" has the meaning set forth in the preamble.

      "PSINET DOCUMENTS" has the meaning set forth in Section 7.4.

      "PSINET MARKS" shall mean the PSINet Primary Marks, the PSINet VAS Marks,
such other Marks as are used by PSINet to promote, advertise and market the
Services, and such other Marks as the Parties shall agree upon in writing.

      "PSINET POINT OF PRESENCE" shall mean one of the points of presence
representing a point of interconnection on the PSINet network. The initial
PSINet Points of Presence are listed in Schedule 6.2 to this Agreement, and
PSINet shall promptly update such schedule during the Term on reasonable notice
to IXC. At any time during the term of this Agreement, PSINet Points of
Presence could be collocated with points of presence on the IXC network
pursuant to Section 6.1.

      "PSINET PRIMARY MARKS" shall mean the Marks "PSINet" and "PSINet" and
logo types thereof all as the same may be changed from time to time.

      "PSINET VAS MARKS" shall mean such Marks as are used by PSINet to
promote, advertise and market Value Added Services.

      "RELEASING PARTY" has the meaning set forth in Section 12.2.

      "RESELLER DOCUMENTATION" shall mean all documentation made available by
PSINet for use by any reseller or distributor of services of the type
comprising the Services to describe the methods and procedures used by PSINet
in the provisioning and support of users of services of the type comprising any
of the Services provided under this Agreement, as such documentation may be
amended, modified or supplemented from time to time.

      "SALES SUPPORT SERVICES" has the meaning set forth in Section 3.1.

      "SERVICES" means Managed Connectivity Services, Value Added Services and
Opportunity Consulting Services.





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<PAGE>
      "TERM" has the meaning set forth in Section 9.1.

      "THIRD PARTY" means an entity other than a Party or any Affiliate of a
Party.

      "TRANSACTION DOCUMENTS" has the meaning set forth in Section 19.1 of the
IRU Agreement.

      "VALUE ADDED SERVICES" or "VAS" has the meaning set forth in Section
2.1.2.

2.          SERVICE DESCRIPTION(S).

      2.1   INITIAL DESCRIPTION OF SERVICES PROVIDED BY PSINET. From and after
the Effective Date, on the terms and subject to the conditions set forth in
this Agreement, PSINet shall provide to IXC, and IXC shall have the right to
purchase from PSINet, the following services:

            2.1.1 Managed Connectivity Services ("MCS"), which consist of the
provision of dial-up and dedicated access to the Internet via the PSINet
network to customers and all related products and services now or hereafter
offered or provided by PSINet that deliver or facilitate such access. The
initial Managed Connectivity Services shall comply with the applicable
descriptions set forth on Schedule 2.2, for PSINet's Intranet, LAN-on-Demand,
InterMAN, InterFrame, Wholesale Dial and InterRamp services, including, without
limitation, the functional, technical and performance requirements set forth in
such Schedule. From time to time, the Parties may agree on such modifications
to the functional, technical and performance requirements for MCS as are
necessary to address requirements of IXC Customers. At such times as PSINet
provides enhanced versions of MCS, PSINet shall make such enhanced versions of
MCS available to IXC, and the Parties may agree, for purposes of this
Agreement, upon the functional, technical and performance requirements for such
services, which requirements shall, at a minimum, ensure that such services
comply with the applicable minimum requirements in Section 2.2.

            2.1.2 Value Added Services ("VAS"), consisting of the following
services and products now or hereafter offered by PSINet or a controlled United
States Affiliate: (i) InternetPaper, (ii) Internet Security Services, (iii)
PSIWeb, (iv) any other services or products developed jointly by the Parties,
and (v) any other services or products now or hereafter marketed or offered by
PSINet as a generally available service or product offering other than MCS
which are not subject to exclusive marketing relationships with Third Parties.
The initial Value Added Services shall comply with the applicable descriptions
set forth on Schedule 2.2. From time to time, the Parties may agree on such
modifications to the functional, technical and performance requirements for VAS
as are necessary to address requirements of IXC Customers. At such times as
PSINet provides enhanced versions of VAS, PSINet shall make such enhanced
versions of VAS available to IXC, and the Parties may agree, for purposes of
this Agreement, upon the functional, technical and performance requirements for
such services, which requirements shall, at a minimum, ensure that such
services comply with the applicable minimum requirements in Section 2.2.

            2.1.3 Opportunity Consulting Services ("OCS"), will consist of
pre-sales technical support and post-sales development and/or implementation
support to address specific IXC-identified market opportunities. At such times
as the situation warrants, the Parties may agree, for purposes of this
Agreement, upon the functional, technical and performance requirements for such
services, which requirements shall, at a minimum, ensure that such services
comply with the applicable minimum requirements in Section 2.2. Certain joint
teaming efforts of the Parties shall be conducted in accordance with Schedule
2.1.3 hereto.

            2.1.4 IXC shall have the right and option to have any other PSINet
services included under this Agreement on terms and conditions reasonably




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<PAGE>
consistent herewith. In addition, upon such time that PSINet discontinues a
service generally among its customers, PSINet may remove such service from this
Agreement, but only after providing IXC with at least 30 days' prior written
notice of its intention to do so. If PSINet so removes a service, PSINet will
continue to honor all existing IXC and IXC Reseller service agreements with end
customers by continuing to make such service available to IXC Customers through
the shorter of (i) the end of the term of their respective service agreements,
and (ii) the end of the two-year period commencing on the expiration of
PSINet's 30-day notice period.

            2.1.5 Notwithstanding anything to the contrary contained herein,
PSINet reserves the right to modify, alter, improve or change any and all of
the PSINet services comprising the Services covered by this Agreement, and this
Agreement will cover the sales of Services as they may be modified, altered,
improved or changed by PSINet from time to time. Subject to Section 2.1.4, in
all cases where such modification, alteration or change will reduce the
functionality of any PSINet service component comprising the IXC Internet
Services, PSINet will not effect such modifications, alterations or changes
without IXC's specific written approval. Such approval will not be unreasonably
withheld, delayed or conditioned.

      2.2   MINIMUM REQUIREMENTS. The MCS, VAS and OCS provided by PSINet under
this Agreement, as described in Schedule 2.2, shall at all times meet the
following minimum requirements:

            2.2.1 The MCS, Internet Security Services and PSIWeb services
provided by PSINet under this Agreement shall be offered and provided with
features and a level of quality that, on average and taken as a whole, equal or
exceed that provided by other leading providers of Internet services offering
comparable services in a substantial portion of the geographic area in which
Services are available pursuant to this Agreement. The Parties agree to work
together on a broader range of service offerings as needed to address market
demand. For purposes of this Agreement, Services shall be deemed to be
available to IXC in any geographic area in which PSINet provides services to
customers or, subject to the last sentence of Section 2.7, in which PSINet has
an Affiliate, strategic partner or other cooperating provider providing
services in such area of the type made available to IXC under this Agreement.

            2.2.2 The MCS and VAS provided by PSINet under this Agreement shall
be offered and provided with features and an overall level of quality that
equals or exceeds that which PSINet offers or provides any other customer.

            2.2.3 The MCS and VAS provided by PSINet under this Agreement shall
comply with all Documentation relating to the MCS and VAS offered or provided
by PSINet as of the Effective Date and as updated from time to time provided
that no such update may operate to have a material adverse impact on (i) any
MCS or VAS (including without limitation the level or quality of service
provided to IXC Customers), taken as a whole, without the prior written consent
of IXC (which shall not be unreasonably withheld, delayed or conditioned),
except to the extent necessary to deal with network emergencies and other
circumstances beyond the control of PSINet, in which case PSINet shall consult
with IXC concerning such change as soon as reasonably practicable, or (ii) any
other Services without providing IXC with advance written notice of such
changes as soon as reasonably practicable.

            2.2.4 PSINet shall not make any changes (i) to any MCS or VAS that
may reasonably be expected to have a material adverse impact on such Service
(including without limitation the level or quality of service provided to IXC
Customers), taken as a whole, without the prior written consent of IXC, except
to the extent necessary to deal with network emergencies and other
circumstances beyond the control of PSINet, in which case PSINet shall consult
with IXC concerning such change as soon as reasonably practicable, or (ii) to
any OCS




                             -5-
<PAGE>
Services provided IXC without providing IXC with advance written notice of such
changes as soon as reasonably practicable.

            2.2.5 The OCS provided to IXC by PSINet shall be performed by
PSINet employees or its subcontractors as deemed by PSINet to be best qualified
and available to perform the task at hand as identified by IXC. Under no
circumstances may PSINet change subcontract relationships in effect at the time
of proposal submission without IXC's specific written approval. Such approval
shall not be unreasonably withheld, delayed or conditioned. PSINet officers
supervising the performance of the services will be empowered to commit the
resources of PSINet to the extent and scope of such officer's authority.

            2.2.6 In the event that Services, as defined herein, or portions of
Services, are provided to IXC by PSINet via a contractual relationship with a
Third Party, PSINet is obligated to maintain such a relationship to the extent
practicable. Should such relationship require that IXC enter into a similar
agreement with the Third Party, PSINet shall use commercially reasonable
efforts to assist IXC in establishing the relationship and securing rates and
levels of service of at least those provided to PSINet by the Third Party.

      2.3   DOCUMENTATION. PSINet represents that (i) Schedule 2.3 contains a
true and complete list of all Documentation relating to the MCS and VAS offered
or provided by PSINet as of the Effective Date, and (ii) true and complete
copies of all such Documentation have been provided to IXC prior to the
Effective Date. In the event PSINet amends, modifies or supplements any such
Documentation, or creates new Documentation in connection with enhanced
versions of MCS or additional VAS added pursuant to Section 1.1, PSINet shall
as soon as practicable provide IXC with written notice of any such amendments,
modifications, supplements or new Documentation, including copies of the
foregoing.

      2.4   LICENSE TO DOCUMENTATION AND OTHER INTELLECTUAL PROPERTY RIGHTS.

            2.4.1 PSINet grants IXC and IXC Resellers a limited, non-exclusive,
royalty-free, license, in the geographic area in which Services are available
to IXC pursuant to this Agreement, throughout the Term, to (i) copy, but not
modify sales literature and product descriptions (Schedule 2.3 list) in any
form, (ii) integrate the Documentation, or any part thereof, into IXC's
catalogs, price lists, brochures and related sales materials, and (iii)
demonstrate, market, distribute and solicit orders for the Services and
warrants that it has such right to grant. The grant of the foregoing license
shall not entitle or in any way be construed to entitle IXC to (a) use PSINet
Marks in connection with IXC's sales, advertisements and promotion of the
Services, except in materials provided (or approved by PSINet prior to IXC's
use thereof) by PSINet; (b) distribute any Services outside the United States
of America in violation of any United States export restrictions; (c)
distribute any Services outside of the geographic areas in which Services are
then available to IXC pursuant to this Agreement; (d) sublicense any of its
rights under this Agreement, except as expressly permitted by this Agreement;
or (e) make any agreement or incur any liability for or on behalf of PSINet
except as expressly contemplated by this Agreement.

            2.4.2 Except for the limited license specifically granted to IXC in
this Agreement, PSINet shall at all times retain full and exclusive right,
title and ownership interest in and to the Services, the PSINet network, all
PSINet Marks and any and all other Intellectual Property Rights or trade secret
rights related thereto. IXC shall notify PSINet of any action by any Third
Party known or suspected by IXC to constitute an infringement of PSINet's
proprietary rights. IXC shall honor all reasonable requests by PSINet, other
than engaging as a party in litigation, to perfect and protect, at PSINet's
expense, any rights of PSINet in the Services, the PSINet network or such
Intellectual Property Rights or trade secret rights.





                             -6-
<PAGE>
            2.4.3 PSINet represents that no further licenses to Intellectual
Property Rights are needed by IXC to market, offer, provision or use the IXC
Internet Services as contemplated by this Agreement, in the geographic area in
which Services are available to IXC pursuant to this Agreement.

      2.5   PSINET LIABILITY FOR AFFILIATE OBLIGATIONS. To the extent that
PSINet's performance of its obligations hereunder causes PSINet to assign or
delegate all or part of its liabilities, obligations and commitments hereunder
to any of its Affiliates, PSINet covenants and agrees that it shall use its
reasonable efforts to cause any such Affiliate to perform such liabilities,
obligations and commitments in accordance with the terms and provisions hereof.
In the event of such an assignment or delegation, PSINet shall remain liable
for all of its liabilities, obligations and commitments hereunder.

      2.6   FORECASTS. The Parties agree to coordinate in estimating the level
and location of demand and traffic for Services during the term of this
Agreement. In that connection, no later than the 15th day of the first month of
each calendar quarter during the term of this Agreement, IXC will provide
PSINet with its projected requirements for each Service, indicating amounts,
types and location during each of the following four calendar months. In the
event that there should be a material change in IXC's proposed requirements as
set forth in the most recent forecast, IXC, as promptly as practicable, shall
update such forecast in order to reflect such change. These forecasts shall be
used for the planning convenience of PSINet and shall not be binding upon IXC,
but PSINet intends to use the forecasts to estimate needed staffing, network
provisioning and product levels for its performance of the terms of this
Agreement and shall only be responsible for using commercially reasonable
efforts to satisfy demand to the extent it materially exceeds such forecasts.
IXC shall provide its initial projected requirements for Services within 15
business days after the Effective Date. All forecasts provided under this
Section 2.6 shall be treated as Confidential Information of IXC pursuant to
Section 10.

      2.7   GEOGRAPHIC SCOPE. It is the intent of the Parties that IXC be
permitted to provide the IXC Internet Services to the IXC Customers, on the
terms and subject to the conditions of this Agreement, in all of the geographic
areas in which PSINet is now, or at anytime during the Term is then, providing
services to its customers. Notwithstanding the foregoing, IXC acknowledges and
understands that PSINet is not now capable of independently providing certain
services in certain geographic areas outside of the continental United States
of America. To the extent that IXC desires to provide IXC Internet Services to
IXC Customers situated in such geographic areas and PSINet has an Affiliate,
strategic partner or cooperating provider offering services therein, IXC may
request that PSINet obtain a quote from such Affiliate, strategic partner or
cooperating provider for such IXC Internet Services. Within five business days
after such request, PSINet shall contact the appropriate Affiliate, strategic
partner or cooperating provider for purposes of obtaining such quote. The
provision of services under this Section 2.7 by such Affiliate, strategic
partner or cooperating partner to PSINet shall be the subject of negotiation
and, if reached by such parties, agreement.*  Notwithstanding anything in this
Agreement to the contrary, PSINet shall not be obligated to provide Services to
an IXC Customer or Third Party in those geographic areas in which PSINet is not
offering services unless (i) it has an Affiliate, strategic partner or
cooperating provider in a particular geographic area, and (ii) such Affiliate,
strategic partner or cooperating provider agrees to provide such services on
terms and conditions to Texas' satisfaction.



*    Confidential material has been  omitted  and filed separately with the
     Securities and Exchange Commission




                                -7-
<PAGE>
      2.8   SERVICES PROVIDED BY IXC. PSINet shall be presented with the
opportunity to execute IXC's standard reseller agreement for IXC service, on
the terms and subject to the conditions set forth in such agreement.


3.    *

      3.1    * From the Effective Date, PSINet shall offer and provide *  as
specified in Schedule 3.1.

      3.2    * PSINet shall create and manage * exclusively for the purpose of
* under Section 3.1.  PSINet shall * with knowledgeable, experienced and
trained Internet professionals capable of providing * consistent with Schedule
3.1.

      3.3    * During the Term, PSINet shall staff the * with * full-time
professionals *.  Any additional * requested by IXC shall be considered as *.
IXC shall reimburse PSINet * incurred in connection with * requested by IXC,
provided that PSINet shall use good business judgment to minimize such
expenses.


4.    CUSTOMER SUPPORT SERVICES.

      4.1   PSINet will provide customer support through its customer support
group or through a Third Party (as determined by PSINet in its sole discretion)
for the Services (other than InterRamp Remote Access services) sold to IXC
Customers as contemplated by this Agreement; provided that PSINet will not be
responsible for providing customer support to any IXC Customer purchasing
Services under a private label which exceeds the level of support which PSINet
is obligated to provide to its customers pursuant to PSINet's service
agreements for the applicable Services, as such agreements may be amended from
time to time. PSINet also may assist IXC with making arrangements for the
provision of customer support with respect to the InterRamp Remote Access
services to be sold to IXC Customers pursuant to this Agreement. IXC
acknowledges, however, that IXC is solely responsible for the provision of such
customer support and PSINet shall have no liability with respect thereto.

      4.2   Notwithstanding the foregoing, IXC shall be responsible for all
pricing and service plans, billing and collections with respect to IXC
Customers.


5. IXC RIGHTS AND RESPONSIBILITIES.

      5.1   IXC USE AND SALES OF SERVICES.

            5.1.1 IXC may use the Services made available to it pursuant to
this Agreement, on the terms and subject to the conditions hereof, (i) for its
own account, (ii) subject to Section 5.1.2, for resale to IXC Customers, or
(iii) subject to Section 5.1.2, for resale to Third Parties for further resale
or distribution (such Third Parties which, notwithstanding the definition of
"Third Parties" herein, include, without limitation, IXC Customers (including
those which are Affiliates of IXC) are referred to herein as "IXC Resellers"),
either alone or in combination with any other products and services. Services
offered by IXC that incorporate MCS and VAS made available to it pursuant to
this Agreement shall, at IXC's discretion, be branded exclusively as IXC
services or otherwise as IXC shall determine. IXC shall specify the design of
any user interface associated with any MCS or VAS, consistent with the
preceding sentence.


*    Confidential material has been omitted and  filed  separately with the
     Securities and Exchange Commission




                               -8-
<PAGE>
IXC will have complete discretion to determine the prices to be charged to IXC
Customers for the Services provided under this Agreement and IXC shall be
solely responsible for establishing and collecting customer charges for
services it or its customers offer through the PSINet network and for preparing
and mailing invoices to IXC Customers. In addition, IXC shall be responsible
for payment of the total amounts invoiced it by PSINet (except for any amounts
disputed by IXC in good faith) regardless of whether IXC is paid by its
customers. Subject to the provisions of Section 5.4, IXC shall also have
complete discretion to determine the other terms and conditions on which IXC
makes such Services available to IXC Customers; provided that neither IXC nor
its customers may offer warranties or representations for the Services that
would obligate or otherwise bind PSINet beyond those stated in the applicable
service agreements.

Except as otherwise provided in this Agreement, except as reasonably necessary
for PSINet to assist IXC during the introduction of IXC Internet Services under
this Agreement, IXC shall provide the primary interface to IXC Customers in
connection with the marketing, offering or provision of IXC services that
incorporate the Services, including (a) providing first tier support for
non-MCS and non-VAS IXC services and (b) handling communications to and
business relations with IXC Customers related to contractual agreements,
handling invoicing and payment matters, and handling inquiries and questions
from IXC Customers about Services.

            5.1.2 Subject to Section 2.7, IXC acknowledges and agrees that it
may not offer for sale or distribution to any IXC Customer or IXC Reseller any
Services until such Services are made generally available by PSINet in the
applicable geographic area. Without limiting the generality of the foregoing,
IXC acknowledges and agrees that no Service may be offered for sale or
distribution by IXC to any IXC Customer or IXC Reseller for multiple end-user
use in any particular geographic area until such Service is made generally
available by PSINet for multiple end-user use in such geographic area (the
"Multiple End-User Restrictions"). IXC will use reasonable efforts to cause
each IXC Reseller to include a provision in its agreements with its customers
that such customer will not engage in any conduct that would violate any of the
Multiple End-User Restrictions.

            5.1.3 Notwithstanding anything in Section 5.1.1 to the contrary,
the Parties agree that the determination of customer interfaces, marketing,
provisioning and delivery for jointly developed new product or services
offerings incorporating IXC services or Services as described herein will be
determined by mutual agreement.

            5.1.4 PERIODIC AUDIT RIGHTS. PSINet shall have the right, upon
reasonable notice and at a date and time mutually agreed upon by the Parties,
to enter the premises of IXC for the purpose of auditing any of IXC's books of
accounts, documents, records (in any media), papers and files (the "IXC
Documents") relating to its compliance with the provisions of this Agreement.
PSINet shall bear the expense of the audit unless the audit reveals that (i)
the amounts collected by PSINet from IXC hereunder are more than two (2)
percent less than that which should have been paid by IXC to PSINet, or (ii)
IXC has not complied with either or both of the first two sentences of Section
5.1.2, in which case, the entire cost of the audit shall be borne by IXC.
Payment of any amounts found due and owing PSINet shall be made promptly by IXC
upon demand by PSINet.

      5.2   USE OF MARKS. Except as provided herein or by advance written
consent of the other Party, each of IXC and PSINet agrees not to (i) display or
use, in advertising or otherwise, any of the other's Marks, (ii) permit any
Affiliate to display or use any of the other's Marks, or (iii) give permission
to display or use any of the other's Marks to any Third Party. Any use by one
Party of any of the other's Marks shall be subject to such other Party's
advance approval in writing, in its discretion, subject to compliance with
guidelines provided by it.




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<PAGE>
Neither Party shall claim ownership or any other rights in any of the other's
Marks. Upon termination or expiration of this Agreement, any and all rights or
privileges granted by IXC or PSINet to use any Marks shall immediately expire
and each Party shall immediately discontinue the use of such Marks. Nothing
herein shall preclude either Party from making factual references to the other
in government filings, disclosure documents and other public statements, except
as otherwise set forth in the IRU Agreement.

      5.3   INTRODUCTORY MARKETING CAMPAIGN. IXC shall have complete discretion
regarding its marketing of the Services provided that neither IXC nor its
customers may offer warranties or representations for the Services that would
obligate or otherwise bind PSINet beyond those stated in the applicable service
agreements or to make any other warranties, promises or representations with
respect to the Services or the PSINet network. In connection with such
marketing activities, IXC shall prominently mention PSINet's role in the
provision of such services in an introductory press release, the content of
which shall be mutually agreed to by the Parties in accordance with Section
19.11 of the IRU Agreement.

      5.4   PROVISIONS APPLICABLE TO END USERS.

            5.4.1 IXC'S USE OF SERVICES. IXC's use of Services in IXC's
capacity as end user of Services for its own account shall be governed by
Schedule 5.4.1 and the terms and conditions of this Agreement generally.

            5.4.2 AGREEMENTS WITH IXC CUSTOMERS OTHER THAN IXC. IXC's
agreements with IXC Customers (other than IXC) to provision Services shall
comply with Schedule 5.4.2.

6.    INFRASTRUCTURE.

      6.1   USE OF IXC EQUIPMENT AND FACILITIES. Except as otherwise agreed to
by the Parties, in providing the Services to IXC under this Agreement, PSINet
may, in its sole discretion, purchase infrastructure, equipment, facilities and
services necessary for the transmission of data (collectively,
"Infrastructure") from IXC provided (i) PSINet is not restricted from
purchasing such Infrastructure from IXC under contractual obligations binding
on PSINet at the time the purchase decision is being considered, (ii) such
Infrastructure meets PSINet's reasonable functional, technical and performance
requirements, and (iii) IXC offers such Infrastructure to PSINet at a price and
on terms and conditions that, on average or taken as a whole, are competitive
as compared to those offered to PSINet in good faith by other leading providers
of infrastructure, equipment, facilities and services similar to the
Infrastructure at the time IXC makes its offer.

      6.2   PROVISIONING OF CUSTOMERS. In connection with the provision of MCS
hereunder, it is the intention of the Parties that IXC shall assume
responsibility for providing, at IXC's expense or the expense of the IXC
Customer, connectivity between the IXC Customer's premises and any PSINet Point
of Presence listed in Schedule 6.2 (as such schedule may be modified or
supplemented from time to time) that is selected by IXC, subject to Section
6.3. PSINet shall assume responsibility for providing and conditioning Customer
premises equipment, consistent with Section 2 herein. Notwithstanding the
foregoing, the Parties acknowledge that the articulation of procedures to
accomplish coordinated provisioning of Services involving a dedicated access
component by the Parties may not be in place for a period after the Effective
Date. During this period, PSINet shall assume this responsibility and shall be
paid at the rates as indicated in Schedule 7.1. IXC shall notify PSINet of its
readiness to transition this responsibility.

      6.3   INTERCONNECTION WITH PSINET FACILITIES. IXC and PSINet shall
coordinate with respect to (i) the definition of the interfaces between the IXC
network and the PSINet network at the PSINet Points of Presence, (ii) the




                         -10-
<PAGE>
management of traffic routed by PSINet from the premises of IXC Customers to
PSINet Points of Presence, and (iii) access by PSINet to the IXC network for
the purposes of providing Services under this Agreement. PSINet shall be
responsible for the day-to-day management of the PSINet network relating to the
provision of Services, including monitoring and taking actions necessary to
remedy problems with, or disruption of, the Services, establishment and
maintenance of routing tables and routing policies at Points of Presence, and
establishment and maintenance of peering points with the global Internet.

      6.4   CUSTOMER TRANSFERS. At any time, IXC shall have the right to
migrate IXC Customers to such services as provided by IXC or on IXC's behalf by
a Third Party. PSINet shall provide all reasonable cooperation in support, to
the extent practicable, of a seamless, minimally disruptive migration of such
IXC Customers in connection with such services (including without limitation
all IXC Customer Information and, to the extent practicable, any necessary
transfer of customer addresses).

      6.5   INTERFACES. The Parties shall develop methods, procedures and
associated interfaces for cooperating on a "seamless" basis in all areas
relating to the marketing and provision of the Services, including without
limitation order processing, customer care, network monitoring and maintenance,
and problem escalation and resolution; PROVIDED, HOWEVER, that PSINet shall in
no event be obligated to provide services or support of any kind to IXC or IXC
Customers which exceeds that which it is required to provide to its own
customers pursuant to PSINet's service agreements for the applicable comparable
services, as such agreements may be amended from time to time. The Parties
shall use commercially reasonable efforts to agree on an initial plan to
accomplish the foregoing, including appropriate training of each other's
employees, by no later than 30 days after the Effective Date. At any time
during the Term, PSINet will cooperate in good faith with IXC in connection
with inquiries concerning potential problems affecting any aspect of the
provision of Services.

7.    PRICING AND PAYMENT.

      7.1   * PSINet shall at all times make sure that all fees and other
charges charged to IXC for each of the individual service components comprising
the Services, as represented in Schedule 2.2, *.

      7.2   INDEPENDENT END-CUSTOMER PRICING. Each of the Parties will have
complete discretion regarding the prices that it charges to its customers for
its services.

      7.3   *

            7.3.1 *.  The term * is defined as * for any individual service
components comprising the Services.  The initial * are set forth in Appendix 1
to Schedule 7.1.  PSINet represents and warrants to IXC that the *.  At such
times as enhancements to existing Services or additional Services are added by
agreement of the Parties pursuant to Section 2.1, * be applicable to IXC's
purchase of such services.

            7.3.2 *.  At all times during the Term, in the event PSINet or any
of its Affiliates enters into a new or renewal agreement or understanding
pursuant to which * for any of the individual service components comprising the
Services * under this Agreement (i) PSINet shall notify IXC promptly of such
event, and (ii) Appendix 1 to Schedule 7.1 shall automatically * shall be in


*    Confidential material has been omitted and filed separately  with  the
     Securities and Exchange Commission




                            -11-
<PAGE>
effect only for so long as that * and, subject to Section 7.3.1, * shall return
to its immediately * upon termination of such period.  Notwithstanding anything
in this Agreement to the contrary, in the event that there should be * shall
not be effective against IXC until PSINet has provided IXC with at least 60
days' prior written notice of *.

            7.3.3 MODIFICATIONS AT REQUEST.  At any time during the Term, IXC
or PSINet may initiate negotiations in the Benchmark Prices as necessary to
ensure that requirements imposed on PSINet under this Agreement * for any
individual service component comprising the Service *.

            7.3.4 CONSIDERATION EXCLUSIONS.  For the purposes of determining *
pursuant to this Section 7 as of any determination date with respect to any
Service, the Parties shall disregard (i) services offered free-of-charge to
employees, employee families, prior * for any individual service component
comprising the Services *.

            7.3.5 PROMOTIONAL PRICING. In addition to the * specified under
this Section 7, the parties shall also agree from time to time on promotional
and other pricing as may be appropriate to take maximum advantage of market
opportunities.

            7.3.6 DISPUTE RESOLUTION. Any dispute relating to the * or any
adjustments thereof, applicable under this Section 7.1 shall be resolved
pursuant to Section 15.18 of this Agreement.

      7.4.  *.  IXC shall have the right, upon reasonable notice and at a date
and time mutually agreed upon by the Parties, *, including, without limitation,
*.  IXC shall bear the expense * hereunder are * service or product, in which
event, * shall be borne by PSINet.*

      7.5   INVOICING AND PAYMENT. During the Term, PSINet shall invoice IXC
for Services delivered to each IXC Customer. Such invoices shall be delivered
by PSINet to IXC in both paper and electronic form with content and formats as
agreed to by the Parties. IXC shall pay PSINet for the Services according to
the schedule set forth in Schedule 7.1. IXC agrees to pay PSINet, in advance,
as invoiced by PSINet, each month during the term, all fees and other charges
with respect to MCS and VAS, and in arrears for OCS, payable under this
Agreement for such month. All such fees for MCS and VAS for the initial month
of service for any IXC Customer shall be prorated for the portion of the month
beginning on the date on which the IXC Customer service commences and ending on
the last calendar day of such initial month and the amount invoiced by PSINet,
with respect to each such IXC Customer shall include such prorated fees and the
fees and charges payable for the following full month.

      7.6   CREDITS/ADJUSTMENTS. All IXC Customers shall be granted service
disruption credits and adjustments, quality of service commitment credits and
adjustments, and the like as may be established by PSINet with respect to
PSINet customers, and as modified from time to time, by PSINet, at its sole
discretion. In the event that IXC, as promptly as practicable, notifies PSINet
after learning of the failure of PSINet to deliver any of the Services to any
IXC Customer, IXC will be entitled to a credit representing any reasonable
adjustment requested by IXC and approved in advance by PSINet as a result of
such failure to meet customer service expectations.

      7.7   LATE PAYMENT. PSINet invoices for amounts payable under this
Agreement shall be due within 30 days of the date of invoice. If a dispute
arises


*    Confidential  material  has been omitted and filed separately with the
     Securities and Exchange Commission




                          -12-
<PAGE>
as to any portion of an invoice, IXC shall pay the undisputed amount of such
invoice when due and shall notify PSINet in writing of the disputed amount no
later than 30 days from the date of invoice.

      7.8   PAYMENT DISPUTE RESOLUTION. In the event of payment dispute, the
PSINet Authorized Representative and the IXC Authorized Representative (as such
capitalized terms are defined in the IRU Agreement) will first attempt in good
faith to promptly resolve the dispute. If the dispute has not been resolved by
the Authorized Representatives within 14 days after IXC's notice, or if either
Party will not agree to meet within such 14-day period, the matter will be
referred to the Chief Executive Officer of PSINet and the Chief Executive
Officer of IXC who will in good faith attempt to resolve the dispute. If the
dispute remains unresolved within an additional 14-day period, the dispute
shall be submitted to arbitration as per the IRU Agreement.

      In the event that any amount remains unpaid after its due date, such
amount shall be subject to an interest charge equal to the lesser of one and
one-half percent of the unpaid balance per month or the maximum rate allowed
under applicable state law and, if such amount shall not have been paid in full
within five business days of the applicable due date when no bona fide dispute
exists, PSINet may, without any liability to IXC, at its option, suspend the
provision of services under this Agreement until such amount is paid in full.

8.    NO RESTRICTIONS.

      Notwithstanding any other provision of this Agreement, except as provided
in Section 2.7, nothing in this Agreement shall limit or in any way affect (i)
the performance of any Party's obligations under a binding agreement in effect
as of the Effective Date (and each Party shall disclose to the other such
agreements that, to such Party's knowledge, are in effect as of such date to
the extent possible consistent with any obligations of confidentiality owing to
Third Parties), (ii) PSINet's right to provide Internet services for its own
account directly to any end user or wholesale customer (subject to section 10)
or otherwise to engage in services involving packet, frame relay, asynchronous
transfer mode or other Internet services, (iii) IXC's right to build, operate
and maintain its own global network, and (iv) either Party's right in any way
to market, offer or provide any products and services that are not, generally,
marketed principally as Internet services.


9.    TERM AND TERMINATION.

      9.1   TERM. The term of this Agreement shall commence on the Effective
Date and shall end on the earlier of (i) the termination of the IRU Agreement,
and (ii) such earlier date as of which this Agreement expires or is terminated
pursuant to Section 9.2.

      9.2   TERMINATION.

            9.2.1 A Party may deliver to the other Party a written "Notice of
Default" in the event that the other Party has breached any Material Provision
hereunder. Such Notice of Default must prominently contain the following
sentences in capital letters: "THIS IS A FORMAL NOTICE OF A BREACH OF CONTRACT.
FAILURE TO CURE SUCH BREACH WILL HAVE SIGNIFICANT LEGAL CONSEQUENCES." A Party
that has received a Notice of Default shall have thirty (30) days to cure the
alleged breach (and, if the defaulting Party shall have commenced actions in
good faith to cure such defaults which are not susceptible of being cured
during such 30-day period, such period shall be extended (but not in excess of
90 additional days) while such Party continues such actions to cure (the "Cure
Period"). If such Party fails to cure the breach within the Cure Period, as
long as such default shall be continuing, the non-defaulting Party shall have
the right to either (i) suspend its performance or payment obligations under
this Agreement




                              -13-
<PAGE>
and/or any of the Transaction Documents (other than obligations under Section
15.8(a) of the IRU Agreement and the Standstill Agreement (as defined in the
IRU Agreement)), (ii) seek an order of specific performance, and/or (iii) seek
the award of compensatory damages.

            9.2.2 PSINet shall terminate, or use commercially reasonable
efforts to terminate, the access rights of any IXC Customer as soon as is
reasonably practicable upon written notice from IXC or any IXC Customer to do
so or upon mutually agreed upon electronic process with receipt confirmed, but
shall have no liability in connection therewith.

            9.2.3 PSINet shall have the right to terminate any IXC Customer on
written notice to IXC (or sooner, if required by law, provided, however that
PSINet should thereafter provide written notice to IXC) in the event of any use
or alleged use by such IXC Customer of the Services or the PSINet network which
is in violation of any law, regulation or treaty, any of the Multiple End-User
Restrictions, PSINet's Net Abuse Policy (available at PSINet's web site at
'http:\\www.psi.net'), any community standard or accepted Internet policy or
which results in the receipt by PSINet of any formal or informal complaint.


10.   CONFIDENTIAL INFORMATION.

      10.1  NONDISCLOSURE. If either Party acquires Confidential Information of
the other, such receiving Party shall maintain the confidentiality of the
disclosing Party's Confidential Information, shall use such Confidential
Information only for the purposes for which it is furnished and shall not
reproduce or copy it in whole or in part except for use as authorized in this
Agreement. Without limiting the generality of the foregoing, neither Party
shall use the Confidential Information of the other Party to solicit the other
Party's customers or to otherwise compete unfairly with the other Party.
Confidential Information shall mean all information of the disclosing Party
which it treats as confidential or proprietary including, without limitation,
all of the following: (i) information concerning customers and the contractual
terms under which services are being provided to such customer by a Party; and
(ii) all customer lists and other information regarding the customers of a
Party. Confidential Information shall not include information which is or
hereafter becomes generally available to others without restriction or which is
obtained by the receiving Party without violating the disclosing Party's rights
under this Article 10 or any other obligation of confidentiality. The terms and
conditions of this Agreement shall constitute Confidential Information. PSINet
and IXC shall cooperate to request confidential treatment as may be mutually
agreed by them with respect to certain terms of this Agreement and the
transactions contemplated hereby in any filing with the Securities and Exchange
Commission, any other government authority or any securities exchange or stock
market.

      10.2  DURATION. With respect to all Confidential Information, the
Parties' rights and obligations under this Article shall remain in full force
and effect following the termination of this Agreement.


      10.3  OWNERSHIP. All materials and records which constitute Confidential
Information, other than service orders and copies of this Agreement, shall be
and remain the property of, and belong exclusively to, the disclosing Party,
and the receiving Party agrees either to surrender possession of and turn over
or to destroy and certify to the other Party the destruction of all such
Confidential Information which it may possess or control upon request of the
disclosing Party or upon the termination of this Agreement.

      10.4  INJUNCTIVE RELIEF. The Parties acknowledge and agree that, in the
event of a breach or threatened breach by any Party of any provision of this
Article, the other Party will have no adequate remedy in money or damages and,




                           -14-
<PAGE>
accordingly, shall be entitled to an injunction against such breach. However,
no specification in this Section of a specific legal or equitable remedy shall
be construed as a waiver or prohibition against any other legal or equitable
remedies in the event of a breach of this Section of this Agreement.

      10.5  LEGAL OBLIGATION TO DISCLOSE. Each Party shall be released from its
obligations under this Section 10 with respect to information which such Party
is required to disclose to others pursuant to obligations imposed by law, rule
or regulation or securities exchange or stock market rule; provided, however,
that prior to any such required disclosure, such Party shall, to the extent
practicable, provide written notice and consult with the other Party.

11.   REPRESENTATIONS AND WARRANTIES.

      11.1  BY PSINET. PSINet represents and warrants to IXC that (i) it is a
corporation duly organized, validly existing and in good standing in the State
of New York; (ii) it has full corporate power and authority to own and operate
the Services and the PSINet network and to carry on its business as presently
conducted; (iii) it has, or has licensed, sufficient right, title and interest
in and to the Services, the PSINet Marks (within the United States) and the
PSINet network; (iv) it has all requisite authority to execute and deliver this
Agreement and to carry out the transactions contemplated hereby; (v) this
Agreement is a valid and binding obligation of PSINet, enforceable against
PSINet in accordance with its terms except as such enforceability may be
limited by laws relating to creditors' rights generally and the exercise of
judicial discretion in accordance with general equitable principles; and (vi)
the licenses granted and obligations owed to IXC hereunder do not conflict with
the rights granted or obligations owed by PSINet to any Third Party.

      EXCEPT FOR THE REPRESENTATIONS AND WARRANTIES SPECIFICALLY SET FORTH IN
THIS SECTION 11.1, PSINET MAKES NO REPRESENTATIONS OR WARRANTIES OF ANY KIND
WHATSOEVER, WHETHER EXPRESS, IMPLIED OR STATUTORY, AND PSINET EXPRESSLY
DISCLAIMS AND EXCLUDES ALL OTHER REPRESENTATIONS AND WARRANTIES OF ANY KIND.
WITHOUT LIMITING THE GENERALITY OF THE FOREGOING, PSINET MAKES NO WARRANTY TO
IXC OR ANY OTHER PERSON OR ENTITY, WHETHER EXPRESS, IMPLIED OR STATUTORY, AS TO
THE DESCRIPTION, QUALITY, COMPLETENESS, MERCHANTABILITY OR FITNESS FOR ANY
PARTICULAR PURPOSE OF ANY INTERNET SERVICE OR ANY OTHER SERVICE PROVIDED
HEREUNDER OR DESCRIBED HEREIN, OR AS TO ANY OTHER MATTER, ALL OF WHICH
WARRANTIES ARE HEREBY EXCLUDED AND DISCLAIMED.

      11.2  BY IXC. IXC represents and warrants to PSINet that (i) it is a
corporation duly organized, validly existing and in good standing in the State
of Delaware; (ii) it has full corporate power and authority to carry on its
business as presently conducted; (iii) it has sufficient right, title and
interest in and to the IXC Marks, (iv) it has all requisite authority to
execute and deliver this Agreement and to carry out the transactions
contemplated hereby; (v) this Agreement is a valid and binding obligation of
IXC, enforceable against IXC in accordance with its terms except as such
enforceability may be limited by laws relating to creditors' rights generally
and the exercise of judicial discretion in accordance with general equitable
principles and (vi) the obligations owed to PSINet hereunder do not conflict
with the rights granted or obligations owed by IXC to any Third Party.

      EXCEPT FOR THE REPRESENTATIONS AND WARRANTIES SPECIFICALLY SET FORTH IN
THIS SECTION 11.2, IXC MAKES NO REPRESENTATIONS OR WARRANTIES OF ANY KIND
WHATSOEVER, WHETHER EXPRESS, IMPLIED OR STATUTORY, AND IXC EXPRESSLY DISCLAIMS
AND EXCLUDES ALL OTHER REPRESENTATIONS AND WARRANTIES OF ANY KIND.

12.   LIMITATION OF LIABILITY.

      12.1  LIMITATION OF LIABILITY. Except for direct damages otherwise
specifically provided for in this Agreement, in no event shall IXC or PSINet be

                              -15-
<PAGE>
liable for any special, incidental, direct, indirect, punitive, reliance or
consequential damages, whether foreseeable or not, arising under this Agreement
or from any breach or partial breach of the provisions of this Agreement or
occasioned by any defect in the Services or other service provided hereunder,
delay in availability of the Services or any service provided hereunder,
failure of the Services or other service provided hereunder, interruptions or
outages of the PSINet network or any other cause whatsoever or arising out of
any act or omission by IXC or PSINet, as applicable, its employees, servants
and/or agents, including but not limited to, damage or loss of data, property
or equipment, loss of profits or revenue, cost of capital, cost of replacement
services, or claims of customers for service interruptions or transmission
problems.

      12.2  RELEASE; INDEMNIFICATION. Each Party (each Party in such capacity
being referred to as the "Releasing Party") releases, assumes and agrees to
indemnify, defend, protect and save the other Party harmless from and against
any claim, damage, loss, liability, cost and expense (including reasonable
attorneys' fees) in connection with any loss or damage to any physical property
or facilities of the Releasing Party or any injury to or death of any Person
arising out of or resulting in any way from the negligence or misconduct of the
Releasing Party or its employees, servants, contractors and/or agents.

13.   INDEMNIFICATION.

      13.1  INDEMNIFICATION OBLIGATIONS. IXC and PSINet (hereinafter where
either has undertaken the action or inaction to be indemnified against shall be
known as the "Indemnifying Party") agree to assume all liability for and
indemnify, defend and hold harmless the other Party or any third Party claiming
through the other Party, from and against all liability, loss, cost, damage,
expense or cause of action, of whatsoever character, or injury or death of any
Person and damage to or destruction of any property, including, without
limitation, third Parties and all related expenses, including, but not limited
to, reasonable attorneys' fees, investigators' fees and litigation expenses and
costs of enforcing this Section 13 arising out of or relating to, in whole or
in part, any of the following:

            (i)   claims for libel, slander, infringement of copyright or
                  unauthorized use of a trade secret, trade name or service
                  mark that results from the transmission of material over the
                  PSINet network by the Indemnifying Party, authorized
                  representatives of the Indemnifying Party or other Persons
                  not associated with, or related to, either IXC or PSINet; or

            (ii)  claims of any Third Party arising out of the negligent or
                  willful act or omission of the Indemnifying Party or its
                  agents, servants, employees, contractors or representatives
                  (other than IXC, if PSINet is the Indemnifying Party, or
                  PSINet, if IXC is the Indemnifying Party); or

            (iii) claims for patent infringement arising out of the use of the
                  PSINet network by the Indemnifying Party or any Person
                  authorized by the Indemnifying Party or resulting from the
                  acts of the Indemnifying Party or the Indemnifying Party's
                  representatives in combining the PSINet network with the
                  facilities of the Indemnifying Party or others, or using the
                  PSINet network either alone or in connection with that of the
                  Indemnifying Party or others; or

            (iv)  claims, except as otherwise set forth herein, for the
                  material breach of or failure to comply, in any material
                  respect, with any term or condition of this Agreement by the
                  Indemnifying Party or its officers, employees or invitees; or

                                  -16-
<PAGE>
            (v)   claims resulting from patent or trade secret infringement or
                  infringement or unauthorized use of trade secrets or trade
                  name by the Indemnifying Party in connection with this
                  Agreement.

      In addition, PSINet will defend, indemnify and hold IXC harmless from and
against any claim or threat of claim by an IXC Customer or an IXC Reseller
which is based on any warranty, promise or representation made by IXC as part
of a service agreement and for which PSINet is responsible in accordance with
the terms of this Agreement. Similarly, IXC will defend, indemnify and hold
PSINet harmless from and against any claim or threat of claim which is based on
any warranty, promise or representation made by IXC to a Third Party for which
PSINet is not responsible in accordance with the terms of this Agreement.

      PROVIDED, HOWEVER, NOTWITHSTANDING ANY PROVISION OF THIS AGREEMENT TO THE
CONTRARY, IN NO EVENT SHALL EITHER PARTY BE LIABLE TO THE OTHER (OR TO ANY
THIRD PARTY CLAIMING THROUGH SUCH OTHER PARTY) FOR CONSEQUENTIAL, INCIDENTAL,
EXEMPLARY OR PUNITIVE DAMAGES, AND THE FOREGOING INDEMNITIES SHALL NOT APPLY
WITH RESPECT TO SUCH DAMAGES.

      13.2  NOTICES AND DEFENSE. The Indemnifying Party shall provide the other
Party with notice of any such claim by a Third Party, and assure the defense of
such claim, on the terms and subject to Sections 9.2 and 9.3 of the IRU
Agreement.

14.   NON-SOLICITATION.

            a.    From the date hereof until three years after the Closing
Date, neither IXC nor any of its Affiliates will, directly or indirectly,
either alone or in association with others in any part of the world induce,
request, encourage or assist any employee of PSINet or its Affiliates to
terminate his or her employment with PSINet, or to join with or become employed
by, render services to or otherwise be engaged by IXC or any of its Affiliates
in any direct or indirect capacity.

            b.    From the date hereof until three years after the Closing
Date, neither PSINet nor any of its Affiliates will, directly or indirectly,
either alone or in association with others in any part of the world induce,
request, encourage or assist any employee of IXC or its Affiliates to terminate
his or her employment with IXC, or to join with or become employed by, render
services to or otherwise be engaged by PSINet or any of its Affiliates in any
direct or indirect capacity.

            c.    If, at the time of enforcement of Section 14, a court shall
hold that the duration, scope, geographic area or other restrictions stated
herein are unreasonable under circumstances then existing, the Parties agree
that the maximum duration, scope, geographic area or other restrictions deemed
reasonable under such circumstances by such court shall be substituted for the
stated duration, scope, geographic area or other restrictions.

15.   MISCELLANEOUS.

      15.1  INDEPENDENT CONTRACTORS. The Parties are acting as independent
contractors and under no circumstances shall any of the employees of one Party
be deemed the employees of the other for any purpose. Except as otherwise
expressly provided in this Agreement, this Agreement does not constitute either
Party as the agent or legal representative of the other Party and does not
create a partnership or joint venture between the Parties. Except as otherwise
expressly provided in this Agreement, neither Party shall have any authority to
act for the other Party in any agency or other capacity, to make commitments of
any kind for the account of, or on behalf of, the other Party or to contract
for or bind the

                                -17-
<PAGE>
other Party in any manner whatsoever. This Agreement confers no rights of any
kind upon any Third Party.

      15.2  FORCE MAJEURE. Notwithstanding any provision in this Agreement to
the contrary, neither Party shall be liable for failure to fulfill its
obligations hereunder (except with respect to payment or other monetary
obligation or as otherwise specifically set forth herein) if such failure is
due to causes beyond its reasonable control, including, without limitation,
actions or failures to act of the other Party or, acts of God, flood, fire,
storm, catastrophe, governmental prohibitions or regulations, viruses which did
not result from the acts or omissions of such Party, its employees or agents,
national emergencies, acts of public enemies, national emergency,
insurrections, riots or wars, breakdown of or damage to plants or equipment or
facilities (other than arising out of the neglect of or mishandling by such
Party), the relevant portion of the Internet is down due to a technology
failure (other than arising out of the neglect of or mishandling by such
Party), failure of a supplier to supply necessary materials or equipment in a
timely manner, destruction of property, embargoes, boycotts, governmental
legislation or regulations, orders or acts of civil or military authorities,
governmental acts or orders of courts or administrative agencies, or strikes,
lockouts, work stoppages or other labor difficulties. The time for any
performance required hereunder shall be extended by the delay incurred as a
result of such act of force majeure, and each Party shall act with diligence to
correct such force majeure.

      15.3  DELAYS OR OMISSIONS. No delay or omission to exercise any right,
power or remedy accruing to a Party under this Agreement shall impair any such
right, power or remedy of such Party nor shall it be construed to be a waiver
of any such breach or default, or an acquiescence therein, or of any similar
breach or default thereafter occurring; nor shall any waiver of any single
breach or default be deemed a waiver of any other breach or default theretofore
or thereafter occurring. Any waiver, permit, consent or approval of any kind or
character on the part of either Party of any breach or default under this
Agreement, or any waiver on the part of either Party of any provisions or
conditions of this Agreement must be made in writing and shall be effective
only to the extent specifically set forth in such writing. All remedies, either
under this Agreement or by law or otherwise afforded to a Party, shall be
cumulative and not alternative.

      15.4  BINDING AGREEMENT. This Agreement shall be binding upon and shall
inure to the benefit of the Parties hereto and their respective successors and
permitted assigns. No Person or entity other than the Parties hereto (and their
respective successors and permitted assigns) is or shall be entitled to bring
any action to enforce any provision of this Agreement against either of the
Parties, and the covenants and agreements set forth in this Agreement shall be
solely for the benefit of, and shall be enforceable only by, the Parties or
their respective successors and assigns as permitted hereunder.

      15.5  ADDITIONAL ACTIONS, DOCUMENTS AND INFORMATION. Each of the Parties
agrees that it will, at any time, prior to, at or after the date hereof, take
or cause to be taken such further actions, and execute, deliver and file or
cause to be executed, delivered and filed such further documents and
instruments and obtain such consents, as may be reasonably requested in order
to fully effectuate the purposes, terms and conditions of this Agreement.

      15.6  NOTICES. (a) All notices and other communications required or
permitted hereunder shall be in writing and shall be mailed by certified or
registered mail (return receipt requested), express air courier, charges
prepaid, or facsimile addressed as follows:

      To IXC:                             with a copy to:

      IXC Internet Services, Inc.         IXC Communications, Inc.

                             -18-
<PAGE>
      500 Plaza on the Lake, Suite 200    5000 Plaza on the Lake,
      Austin, TX 78746-1050               Suite 200, Austin,
      Attn: Chairman                      TX 78746
      Facsimile: (512) 328-0239           Attention: General Counsel
                                          Facsimile: (512) 328-7902

                                          Riordan & McKinzie
                                          695 Town Center Drive,
                                          Suite 1500
                                          Costa Mesa, California 92626
                                          Attn: Michael P. Whalen
                                          Facsimile: (714) 549-3244

      To PSINet:                          with copy to:

      PSINet Inc.                         PSINet Inc.
      510 Huntmar Park Drive              510 Huntmar Park Drive
      Herndon, Virginia 20170             Herndon, Virginia 20170
      Facsimile: 703.397.5318             Facsimile: 703.904.9527
      Attn: Vice President and            Attn: General Counsel
            General Manager,
            Wholesale Group


or to such other address as either Party shall have furnished to the other in
writing.

            (b) If a notice is given by either Party by certified or registered
mail, it will be deemed received by the other Party on the fifth business day
following the date on which it is deposited for mailing. If a notice is given
by either Party by air express courier, it will be deemed received by the other
Party on the next business day following the date on which it is provided to
the air express courier. If a notice is given by facsimile, it will be deemed
received by the other Party after confirmation of receipt. Notwithstanding the
foregoing, any payments made under this Agreement shall be deemed received only
when actually received.

      15.7  ATTORNEYS' FEES. If any arbitration is commenced between the
Parties regarding the performance of this Agreement, the prevailing Party shall
be entitled, in addition to such other relief as may be granted, to a
reasonable sum for its attorneys' fees in such proceeding and for the expenses
and costs of such proceeding as the arbitrator may determine.

      15.8  ASSIGNMENT. No assignment of this Agreement or of any rights or
obligations hereunder may be made by either Party without the prior written
consent of the other Party hereto and any attempted assignment without the
required consent shall be void; PROVIDED, HOWEVER, that notwithstanding the
foregoing, (i) each Party shall have the right to pledge, assign or otherwise
transfer this Agreement and its rights hereunder, in whole or in part, as
collateral security to any lender, and (ii) each Party shall have the right to
assign or transfer this Agreement and its rights hereunder, in whole or in
part, to any direct or indirect wholly-owned subsidiary of that Party or to any
Person into which that Party may be merged or consolidated or which purchases
all or substantially all of the assets of that Party; PROVIDED, HOWEVER, that
(a) such subsidiary or Person agrees to be bound by the terms of this Agreement
and (b) any such assignment or transfer shall not relieve that Party from any
liability or obligation under this Agreement.

      15.9  NO THIRD PARTY BENEFICIARIES. No provision to this Agreement is
intended, nor shall any be interpreted, to provide or create any Third Party
beneficiary rights or any other rights of any kind in any client, customer,
affiliate, shareholder, partner of any Party or any other Third Party; unless

                               -19-
<PAGE>
specifically provided otherwise herein, and except as so provided, all
provisions hereof, shall be personal solely between the Parties to this
Agreement.

      15.10 EXPORT CONTROLS. IXC agrees and acknowledges that any export of the
Services and the subsequent use thereof is subject to U.S. export control laws
and regulations. IXC shall not directly or indirectly transfer the Services, or
the documentation relating thereto, to any country or location outside of the
United States without obtaining the prior written consent of PSINet.

      15.11 SEVERABILITY. In case any provision of this Agreement shall be
invalid, illegal or unenforceable, such provision shall be construed so as to
render it enforceable and effective to the maximum extent possible in order to
effectuate the intention of this Agreement; and the validity, legality and
enforceability of the remaining provisions hereof shall not in any way be
affected or impaired thereby.

      15.12 PUBLIC ANNOUNCEMENTS. Each Party shall have the right to review,
comment upon and approve any publicity materials, press releases or other
public statements by the other that refer to, or that describe any aspect of,
this Agreement made prior to, or within 90 days after, the Effective Date;
PROVIDED, HOWEVER, that with respect to disclosure documents required under the
Securities Exchange Act of 1934, as amended, subject to the last sentence of
this Section 15.12, each Party shall only have the right to prior review and to
comment upon the other Party's disclosure documents. Each Party agrees that it
will not issue any such publicity materials, press releases or public
statements without the prior written approval of the other Party. The
provisions of this section shall survive termination of this Agreement for a
period of two years, except for the last sentence hereof which shall survive as
may be mutually agreed by them for the Term.

      15.13 EXPENSES. Each Party shall pay its own legal and other costs
incurred in connection with this Agreement and in the preparation for and
consummation of the transactions provided for herein.

      15.14 TAXES. IXC shall be liable for and shall reimburse PSINet for all
taxes and related charges, however designated, resulting from the provision of
Services as contemplated hereby, including federal, state, provincial or local
sales, use or value-added taxes (VAT) and excise taxes, imposed in connection
with or arising from the provision of Services. In no event shall IXC be
obligated to pay income taxes levied upon PSINet's net income or any real or
personal property taxes assessed against PSINet or PSINet's property, including
any gross receipts taxes assessed in lieu of net income or property taxes,
provided that, if the terms of the relevant statute or ordinance imposes such
gross receipts tax upon IXC, then IXC shall be liable for such tax.

      15.15 SURVIVAL OF OBLIGATIONS. The Parties' rights and obligations that,
by their nature, would continue beyond the termination, cancellation, or
expiration of this Agreement, shall survive such termination, cancellation or
termination.

      15.16 TITLES AND SUBTITLES. The titles of the Articles and Sections of
this Agreement are for convenience of reference only and are not to be
considered in construing this Agreement.

      15.17 GOVERNING LAW. This Agreement shall be governed in all respects by
the laws of the State of Delaware without reference to its principles of
conflicts of laws.

      15.18 DISPUTE RESOLUTION. Any controversy or claim arising out of or
relating to this Agreement or with respect to an alleged breach of the terms
hereof, subject to Section 7.8, above, shall be resolved in accordance with the
provisions of Section 19.14 of the IRU Agreement.


                                 -20-
<PAGE>
      15.19 ENTIRE AGREEMENT/AMENDMENTS. This Agreement and the Reciprocal
Confidentiality Agreement constitutes the full and entire understanding and
agreement between the Parties with regard to the subjects hereof and supersedes
all prior oral and written agreements, commitments and understandings with
respect to such matters. Neither this Agreement nor any term hereof may be
amended, waived, discharged or terminated, except by a written instrument
signed by the Parties hereto.

      15.20 COUNTERPARTS. This Agreement may be executed simultaneously in two
or more counterparts, each counterpart shall be deemed to be an original, and
all counterparts individually or together shall constitute one and the same
instrument.

      15.21 SCHEDULES. The information set forth in the following Schedules to
this Agreement is intended to supplement the information contained in this
Agreement. In the event of any conflict between the terms of this Agreement and
the information contained in the Schedules hereto, the terms of this Agreement
shall prevail and control.

BOTH Parties represent and warrant that the Person whose signature appears
below is duly authorized to enter into this Agreement on behalf of the Party.

IN WITNESS WHEREOF, THE PARTIES HAVE ENTERED INTO THIS AGREEMENT AS OF THE
EFFECTIVE DATE:

IXC Internet Services, Inc.               PSINet Inc.

By:   /s/   RALPH J. SWETT                By:   /s/   WILLIAM L. SCHRADER
Name:       RALPH J. SWETT                Name:       WILLIAM L. SCHRADER
Title:      CHAIRMAN, PRESIDENT AND CEO   Title:      CHAIRMAN, PRESIDENT AND
                                                      CEO
Date:       7/22/97                       Date:       7/22/97

                               -21-
<PAGE>
                         SCHEDULE 2.1.3

                    MASTER TEAMING AGREEMENT


DEFINITIONS:

      "CLIENT" refers to a major domestic or worldwide corporation which either
issues a request for Proposal or would be receptive to an unsolicited Proposal
for procurement of products and/or services of the types provided by the
Parties.

      "PROJECT" refers to a certain procurement of services by and delivery to
Client.

      "PROPOSAL" refers to the documentation of the plan, approach,
methodology, deliverables, costs, etc. submitted to a Client.

      "TEAM LEADER" shall mean the Party submitting the proposal to Client and
fulfilling the leadership role in Project management.

      "TEAM MEMBER" shall mean the Party who is not the Team Leader.

      All other capitalized terms used herein but which are not otherwise
defined shall have the meanings given to them in the Joint Marketing and
Services Agreement to which this Schedule 2.1.3 is attached (the "Marketing
Agreement").


ARTICLE I - INTRODUCTION AND SCOPE.

1.1   With respect to IXC, this Agreement applies only to the Internet Services
      and Broadband Services divisions of IXC and to teaming efforts regarding
      the products and services of such divisions. In addition, this Agreement
      shall apply only to teaming efforts regarding products and services to be
      sold and/or provided in the Territory, except as stated below. The
      Parties acknowledge that Projects may be performed outside the Territory
      either directly or indirectly through local subsidiaries or
      subcontractors and may be under this Agreement or under separate
      agreements of their respective local subsidiaries, all as the Parties may
      agree from time-to- time. The Parties will endeavor to ensure that the
      provisions of any such separate agreement, to the extent reasonably
      possible, will be the same as those of this Agreement. However, because
      of the various legal and business requirements of such subsidiaries or
      imposed on such subsidiaries, certain modifications of the provisions of
      this Agreement may be required for its adoption for use in such
      instances.

1.2   This Agreement applies only to the preparation and submission of
      Proposals and other related activities and performance of the Parties in
      order to obtain a contract from the applicable Client. The provision of
      products and/or services by a Party hereto as subcontractor to the other
      Party hereto as prime contractor will be under a separate agreement, as
      stated in Section 2.3 of this Agreement.

1.3   Either Party may request the other Party's participation in the
      development of a Proposal. Such request will be in writing in the form of
      a Statement of Intent To Develop A Proposal (the "Statement of Intent")
      substantially in the form of Exhibit A hereto, signed by a requesting
      Party. Such Statement of Intent may contain a brief preliminary
      description of the products and services each Party would provide, with
      the full description of the products and services to be provided by a
      Party as subcontractor to the other Party as prime contractor, and the
      applicable fees and charges, to be agreed upon and completed at a later




                          Schedule 2.1.3
                            Page 1 of 12

<PAGE>
      date and incorporated in a subcontract to be negotiated and executed by
      the Parties with respect to the applicable Project. The Party receiving
      such a request to participate will respond in writing as to whether or
      not it will participate in the Proposal and Project by the earlier of (i)
      ten (10) business days after its receipt of the request, or (ii) thirty
      (30) days prior to the due date of the Proposal. A Party's election to
      participate shall be effected by executing and returning the Statement of
      Intent. An election to decline the offer to participate shall be effected
      by sending written notice of this decision to the offering Party. In the
      event of an election to decline participation, the following provisions
      of this Agreement will not apply to the applicable Proposal and Project:
      Articles III, IV and V, and Section 2.3.


ARTICLE II - RELATIONSHIP OF THE PARTIES.

2.1   The Parties shall act as independent contractors in the performance of
      this Agreement. Neither Party shall act as agent for or partner of the
      other Party for any purpose whatsoever, and the employees of one Party
      shall not be deemed the employees of the other Party.

2.2   Nothing in this Agreement shall be construed to grant either the Team
      Leader or the Team Member the right to make commitments of any kind for
      or on behalf of the other Party without the prior written consent of the
      other Party.

2.3   It is understood and agreed that, in the event a contract is awarded to
      the Team Leader by the Client, the Team Leader will be the prime
      contractor. In such event, the Team Leader agrees, subject to the
      Client's approval, promptly upon receipt of the contract award, to
      negotiate in good faith a subcontract with the Team Member for
      performance of its proposed portions of the Project. The Parties agree to
      use reasonable efforts to negotiate and agree upon model form subcontract
      agreements which shall be used as standard form agreements, to the extent
      reasonably possible, between Team Leader and Team Member for Team
      Member's provision of products and or services with respect to Projects.


ARTICLE III - PROPOSAL PREPARATION AND SUBMISSION TO CLIENT.

3.1   Each Party shall use reasonable commercial efforts to prepare its
      portions of the Proposal for a Project and to obtain the award to the
      applicable prime contractor hereunder of a contract for the Project.

3.2   The Team Member shall submit to the Team Leader all necessary technical
      and business data and information concerning its proposed portion of the
      Project, including pricing data, required for use in preparation of the
      Proposal. The Team Member shall make available appropriate and
      high-quality personnel to provide reasonable assistance to the Team
      Leader in the preparation of the Proposal as directed by the Team Leader.

3.3   The Team Leader shall prepare the Proposal, integrate the information
      provided by the Team Member and submit the Proposal to the Client. The
      Team Leader agrees to consult with the Team Member on all matters
      concerning the portion of the Project to be performed by the Team Member
      prior to submission of the Proposal to the Client.

3.4   The Team Leader shall identify the Team Member as a proposed
      subcontractor and describe the Team Member's Project responsibilities in
      the Proposal.





                          Schedule 2.1.3
                             Page 2 of 12

<PAGE>
3.5   The Team Leader shall handle contract negotiations with the Client and,
      subject to Client approval, the Team Member will have the opportunity to
      be present at meetings with the Client related to its proposed portion of
      the Project.

3.6   The Team Leader agrees to consult with and obtain the concurrence of the
      Team Member prior to making any Proposal change relating to the Team
      Member's proposed portion of the Project.

3.7   The Team Leader agrees to keep the Team Member advised of all changes in
      the Client's requirements affecting the Team Member's proposed portion of
      the Project and as to the probability of contract award to the team.

3.8   The Team Leader shall use its best efforts to obtain the contract award,
      including participation in oral presentations and preparation of best and
      final offers, and the Team Member agrees to assist in such efforts as the
      Team Leader may reasonably require.

3.9   All contacts with the Client with respect to the Project Proposal shall
      be the responsibility of the Team Leader. Any contacts made by the Team
      Member with the Client shall be only with the full knowledge, prior
      concurrence and participation of the Team Leader.


ARTICLE IV - PROJECT SUBCONTRACT.

4.1   In the event of a contract award to the Team Leader, the Parties shall
      immediately commence good faith negotiations of a subcontract consistent
      with the terms of this Agreement, the applicable Proposal, and the
      applicable prime contract, as may be appropriate, encompassing the Team
      Member's proposed portion of the Project. The Team Leader agrees to use
      its best efforts to secure approval of such subcontract by the Client in
      the event such approval is necessary. Team Leader, with Team Member's
      agreement, may authorize Team Member to begin work, at the direction of
      the Team Leader, prior to execution of the subcontract, for the specific
      Project, subject to the terms of the model form subcontract agreement
      referred to in Section 2.3, above.

4.2   The specific work to be performed by the Team Member will be described in
      the applicable subcontract and/or in orders issued thereunder by Team
      Leader from time to time. Article V below describes generally the
      products and services to be provided by the Parties with respect to
      Projects.

4.3   The subcontract with the Team Member shall include, among other
      appropriate provisions, those provisions for the prime contract between
      the Team Leader and the Client which the prime contract requires are to
      be flowed down to a subcontractor, provided that Team Member either was
      aware of such flow-down requirement before preparation of Team Member's
      portion of the Proposal or subsequently agrees to such provisions. Team
      Member will advise Team Leader, prior to submission of the Proposal, of
      any such flow-down provisions of the proposed Client prime contract as to
      which Team Member takes exception; any such provisions, of which Team
      Member was aware, to which exception is not taken will be included in the
      subcontract.


ARTICLE V - GENERAL RESPONSIBILITIES FOR PRODUCTS AND SERVICES.

5.1   IXC generally will provide products and services of the following types
      for Projects:





                          Schedule 2.1.3
                           Page 3 of 12

<PAGE>
                                  [TO FOLLOW]

5.2   "CORPORATION" generally will provide products and services of the
      following types for Projects:

                                  [TO FOLLOW]


ARTICLE VI - COST AND EXPENSES.


6.1   Each Party will bear all of its own costs and expenses relating to the
      preparation of Proposals and to the performance of its other obligations
      and activities under this Agreement. Neither Party will charge the other
      Party for any services unless specifically agreed otherwise in writing by
      the Parties.


ARTICLE VII - PROPRIETARY INFORMATION.


7.1   Each Party anticipates that it may be necessary to provide access to
      information of a confidential or proprietary nature (hereinafter referred
      to as "Proprietary Information") to the other Party in the performance of
      this Agreement. To the extent possible, Proprietary Information shall be
      clearly identified or labeled as such by the disclosing Party at the time
      of disclosure. Where concurrent identification of such information is not
      feasible, the disclosing Party shall provide such identification as
      promptly thereafter as possible. However, whether or not so designated,
      each Party's client lists, business plans, and the pricing of its
      products and services will be deemed the confidential information of such
      Party.

7.2   Each Party agrees that it will hold such Proprietary Information
      confidential in the same manner as it holds its own Proprietary
      Information of like kind, but in any case, by the use of at least
      reasonable care. Disclosures of Proprietary Information shall be
      restricted to those individuals who are participating in preparation of
      the Proposal and other work related to the Project. Each Party shall
      return all such Proprietary Information of the other upon termination of
      the Agreement and completion of all pending Projects.

7.3   Neither Party shall reproduce, disclose or use Proprietary Information of
      the other except as follows:

(a)   Proprietary Information furnished by the Team Leader may be used by the
      Team Member in performing its obligations under this Agreement and any
      resulting subcontract.

(b)   Proprietary Information furnished by the Team Member may be used by the
      Team Leader in performing its obligations under this Agreement, including
      preparation of the Proposal for submission to the Client, and in
      performance of a resulting subcontract between the Parties for a Project.

(c)   Proprietary Information furnished by either Party may be used in
      accordance with written authorization received from the disclosing Party.

7.4   The limitations on reproduction, disclosure, and use of Proprietary
      Information shall not apply to, and neither Party shall be liable for,
      reproduction, disclosure or use of Proprietary Information of the other
      to the extent such information: (1) becomes known to the public from a
      source other than the receiving Party; (2) was or becomes known to the
      receiving




                          Schedule 2.1.3
                           Page 4 of 12

<PAGE>
      Party from a Third Party having the right to disclose it and having no
      obligation of confidentiality to the disclosing Party with respect to the
      applicable information; (3) is furnished to others by its owner without
      restriction on disclosure; (4) is independently developed by personnel of
      the receiving Party who have not had access to such information; or (5)
      is disclosed pursuant to governmental or judicial requirement.

7.5   Neither the signing of this Agreement nor the furnishing of any
      Proprietary Information by either Party to the other shall be construed
      as granting the other Party expressly, by implication, by estoppel or
      otherwise, any license under any invention, patent, trademark, copyright
      or other proprietary right now or hereafter owned or controlled by the
      Party disclosing and furnishing same.

7.6   Each Party admits for all purposes that any violation or threatened
      violation of this Article VII shall constitute an irreparable injury to
      the disclosing Party for which monetary damages provide an inadequate
      remedy, and agrees that, in addition to all other rights provided by law
      to which the disclosing Party shall hereby be entitled, it shall have the
      right to seek to have an injunction or equivalent remedy issued against
      the receiving Party to prevent said Party from violations or further
      violations of this Article VII.

7.7   The provisions of this Article VII shall survive termination of this
      Agreement and any Proposal effort.


ARTICLE VIII - INTELLECTUAL PROPERTY RIGHTS.


8.1   All rights in and to inventions conceived and/or reduced to practice, and
      in and to works of authorship created in the performance of this
      Agreement (and any resulting subcontracts signed by the Parties for a
      Project, except as the Parties agree otherwise in any such subcontracts)
      shall be the sole and entire property of the originating Party, including
      full ownership and title to related patents, copyrights and other
      intellectual property. In the event of joint inventions or joint works or
      authorship, the Parties shall engage in good faith negotiations to
      establish respective ownership rights therein. Failing agreement within
      thirty (30) days from initiation of good faith negotiations by either
      Party, [the Parties shall be deemed to have joint ownership, without
      right of account, of the intellectual property rights embodied in such
      new inventions and/or works of authorship.]

8.2   Notwithstanding the foregoing, with respect to any Proposal effort by the
      Parties, it is understood and agreed that Team Member shall grant a
      license or transfer rights to Team Leader and/or the Client in
      inventions, works of authorship, data and information as required by the
      terms of the applicable request for Proposal for a Project, provided that
      Team Member was aware of such terms at the time Team Member prepared its
      portion of the Proposal, and except to the extent exceptions are taken to
      the applicable provisions of the request for Proposal. Such license or
      transfer of rights shall not exceed the requirements of the prime
      contract for such Project. Intellectual property rights embodied in
      preexisting equipment or computer software shall remain the sole property
      of its then owner, PROVIDED, HOWEVER, such owner hereby agrees to license
      such software for use by the Client to the extent required by the prime
      contract.







                          Schedule 2.1.3
                          Page 5 of 12

<PAGE>
ARTICLE IX - NON-EXCLUSIVITY/EXCLUSIVITY OF RELATIONSHIP.

9.1   Except as stated below, the participation of the Parties in a Project
      under this Agreement shall be on a non-exclusive basis, and each Party
      shall retain complete freedom to work alone or with other Third Parties
      in bidding or performing work on any such Project. However, on a
      case-by-case basis, the Parties may agree, with respect to any particular
      Project, to participate with each other on an exclusive teaming basis,
      and, in the event of such an agreement to team exclusively, it shall be
      under the following terms.

(a)   [Neither Party may enter into or participate in a teaming agreement or
      effort with another Third Party for the purpose of proposing to provide
      products or services for a Project subject to this Agreement of the types
      for which it is responsible under this Agreement.]

(b)   [Neither Party may quote, offer to provide, provide, offer to sell, or
      sell to the applicable Client or to any prime or subcontractor to the
      applicable Client any products or services relating to the applicable
      Project of the types for which it is responsible under this Agreement,
      other than pursuant to a Proposal under this Agreement or a subcontract
      between the Parties.]

(c)   [With respect to IXC, the exclusive teaming obligations and restrictions
      stated above shall apply only to its IXC Internet Services division, and
      the other divisions and business units of IXC Communications, Inc. are
      free of any such obligations and restrictions.]

(d)   Notwithstanding the foregoing, in the event that any other division of
      IXC invites IXC Internet Services division to participate with it in any
      Proposal for any Project or to provide any products or services with
      respect to a Project, IXC Internet Services division may do so, provided
      that such other division of IXC became aware of such Project other than
      through a violation of the rights of "Corporation" regarding protection
      of its Proprietary Information under this Agreement. In the event the IXC
      Internet Services division participates or provides any products or
      services as described above in this Section 9.1(d), both Parties to this
      Agreement will be relieved of and discharged from the exclusive teaming
      obligations and restrictions stated above with respect to the applicable
      Proposal and Project.

9.2   The Parties will be relieved of and discharged from the above exclusive
      teaming obligations and restrictions to the extent that either Party's
      participation in the applicable Project with any other Third Party is
      pursuant to any agreement executed prior to its agreement to team
      exclusively hereunder. Each Party will exert best efforts to advise the
      other Party of any such previously existing agreement as soon as
      possible. In the event that a Party participates in a Project with a
      Third Party under the circumstances described above in this Section 9.2
      and that such Party is relieved of and discharged from the said exclusive
      teaming obligations and restrictions under this Section 9.2, the other
      Party may, at its option, terminate the applicable Proposal under this
      Agreement and/or participate in the Project itself, independently of the
      other Party, or with any other Third Party, and will be deemed relieved
      of and discharged from the above-referenced exclusive teaming obligations
      and restrictions.

9.3   The Parties will be relieved of and discharged from the above exclusive
      teaming obligations and restrictions to the extent provided under Section
      15.4, below, regarding termination of a Proposal effort.





                          Schedule 2.1.3
                          Page 6 of 12

<PAGE>

ARTICLE X - LIMITATION OF LIABILITY.

10.1  NEITHER PARTY WILL BE LIABLE FOR ANY INDIRECT, SPECIAL, PUNITIVE,
      INCIDENTAL OR CONSEQUENTIAL DAMAGES OF ANY KIND (INCLUDING, BUT NOT
      LIMITED TO, LOST PROFITS) INCURRED OR ARISING OUT OF THE PERFORMANCE OF
      THIS AGREEMENT EVEN IF THAT PARTY HAS BEEN ADVISED OF THE POSSIBILITY OF
      SUCH DAMAGES.


ARTICLE XI - NON-SOLICITATION.

11.1  Neither Party shall actively solicit for employment any of each other's
      personnel during the period of such employees' assignment to or work on
      any Proposal and for the period of six (6) months following termination
      of assignment of each such employee to the Proposal effort. Publicizing
      available employment positions in newspapers or other media of mass
      communication shall not be deemed active solicitation for employment
      under this provision.


ARTICLE XII - FORCE MAJEURE.

12.1  Neither Party shall be liable for any failure to perform or for any delay
      in performance of this Agreement where the failure or delay is due to
      acts of God or public enemy, war, riot, embargo, fire, explosion,
      sabotage, flood, accident, strikes, lockouts or other labor disturbances
      or to enactment, promulgation or issuance of any laws, regulations,
      orders or decrees of any competent governmental, regulatory or judicial
      authority, or, without limiting the foregoing, to any circumstances
      beyond such Party's reasonable control. During such period of disability,
      each Party's obligations will be suspended and commensurately extended
      until such time as performance is no longer prevented or hindered,
      provided that if such period extends for the shorter of (I) thirty (30)
      days, or (ii) a period of such duration that either Party consequently
      reasonably determines that affected Proposal efforts are jeopardized,
      either Party thereafter may terminate this Agreement as it applies to any
      adversely affected Proposal, if such right is exercised before the
      disability is remedied and performance is resumed.


ARTICLE XIII - PUBLIC ANNOUNCEMENT.

13.1  Any news release, public announcement, advertisement or publicity
      released by either Party concerning this Agreement, any Proposal, or any
      contract award related thereto, will be subject to the prior review,
      comment and approval of the other Party, except that this Agreement and
      its terms may be disclosed by either Party as required by any law,
      regulation or court order. Any such publicity shall give due credit to
      the contribution of each Party.


ARTICLE XIV - GOVERNING LAW.

14.1  This Agreement shall be construed in accordance with the local law of the
      State of Texas.









                          Schedule 2.1.3
                           Page 7 of 12

<PAGE>
ARTICLE XV - TERM AND TERMINATION OF AGREEMENT AND PROPOSAL EFFORTS.

15.1  This Agreement is effective upon execution by both Parties and will
      continue in effect thereafter for an initial term of one (1) year.
      Thereafter, the term of this Agreement will be deemed renewed
      automatically, subject to termination as set forth below or as other-wise
      provided in this Agreement.

15.2  Either Party may terminate this Agreement, for its convenience, with or
      without cause, upon at least thirty (30) days advance written notice to
      the other Party, effective as of the end of the initial term or at any
      time thereafter. With respect to the performance of obligations regarding
      any Proposal which would extend beyond the termination of this Agreement,
      the provisions of this Agreement applicable to such performance and the
      corresponding rights and obligations of the Parties will be deemed to
      survive the termination of this Agreement and continue in effect as
      required for the completion of such performance.

15.3  With respect to a Proposal, the rights and obligations of the Parties
      under this Agreement, except any obligations relating to the protection
      of a Party's confidential information, shall terminate upon the first to
      occur of any of the following events:

(a)   cancellation of the applicable request for Proposal or modification of
      the said request for Proposal resulting in the deletion of the
      requirement of the Team Member's products or services or a substantial
      portion thereof;

(b)   elimination by the Client of the Team Leader from consideration as prime
      contractor or award of the prime contract to a company other than the
      Team Leader);

(c)   award of a prime contract to the Team Leader which does not include the
      Team Member's products or services or a substantial portion thereof;

(d)   notification by the Client that the Team Member is unacceptable as a
      subcontractor, or a direction by the Client to utilize a subcontractor
      other than the Team Member, or a determination by either, the Client or
      the Team Leader that the Team Member's offerings do not fully comply with
      the mandatory requirements of the request for Proposal;

(e)   notification of termination by either Party in the event the Parties are
      unable to agree, negotiating in good faith, on the terms and conditions
      of the SUBCONTRACT, within sixty (60) days (or such longer period as the
      Parties may agree) from the award of a prime contract to Team Leader.

(f)   execution of the applicable subcontract between the Parties;

(g)   filing by or against either Party of a petition or a resolution made or
      passed by either Party for the bankruptcy, winding-up, liquidation or
      dissolution of such Party, or the appointment of a receiver or trustee in
      respect of such Party or of its assets, or the acknowledgment by such
      Party of its inability to meet its debts as they fall due, or a general
      assignment of the assets of such Party for the benefit of its creditors;

(h)   termination by either Party under Article XII of this Agreement;

(i)   determination, made reasonably and in good faith, by Team Leader to
      withdraw a Proposal for the reason that it has no reasonable prospect of
      being awarded the prime contract, making continuation of the Proposal
      effort uneconomical or impractical.





                          Schedule 2.1.3
                           Page 8 of 12

<PAGE>
(j)   notification of termination, effective thirty (30) days after such
      notification, by a Party to the other Party as a result of a material
      breach or default of this Agreement by the other Party which is not
      cured, corrected or remedied by the expiration of such thirty-day period;

15.4  In the event any Proposal effort is terminated under Sections 15.3(a)
      through (i), above, both Parties will be deemed relieved of and
      discharged from any exclusive teaming obligations and restrictions under
      Article IX or any other exclusive teaming provision with respect to the
      applicable terminated Proposal effort. In the event a Party terminates
      any Proposal effort as a result of the other Party's breach under Section
      15.3(j), above, such terminating (non-breaching) Party will be deemed
      relieved of and discharged from any exclusive teaming obligations and
      restrictions as stated above in this Section 15.4. Except as otherwise
      stated in this Section 15.4 or elsewhere in this Agreement, the said
      exclusive teaming obligations and restrictions will survive such
      termination.


ARTICLE XVI - CONDUCT OF THE PARTIES.

16.1  Neither Party, in the performance of this Agreement, shall take any
      action that would be illegal under any applicable rule, regulation or
      law. The Parties and their respective business associates shall avoid any
      practices that are unlawful, improper or unethical and shall conduct
      themselves at all times in a manner that will avoid any appearance of
      impropriety on the part of either Party in the event of public
      disclosure.


ARTICLE XVII - SURVIVAL.

17.1  In addition to those provisions hereof expressly stated to survive this
      Agreement, any provisions of this Agreement and the related rights and
      obligations of the parties which, by their nature, should survive
      termination of this Agreement, will so survive and continue in effect as
      appropriate.


ARTICLE XVIII - GENERAL.

18.1  All notices, requests, consents and other communications hereunder shall
      be deemed to have been duly given if delivered in accordance with Section
      15.6 of the Marketing Agreement.

18.2  Except as otherwise stated in this Agreement or the Marketing Agreement,
      this Agreement may not be assigned or otherwise transferred by either
      Party, in whole or in part, without the express prior written consent of
      the other Party. No provision of this Agreement may be waived except by a
      writing by the Party to be charged, nor may this Agreement be amended
      except by a writing executed by an authorized representative of each
      Party.

18.3  The foregoing represents the complete and exclusive statement of the
      agreement between the Parties and supersedes any prior oral or written
      agreements, Proposal, commitments, understandings, or communications with
      respect to the subject matter of this Agreement.




                          Schedule 2.1.3
                          Page 9 of 12

<PAGE>
      IN WITNESS WHEREOF, the Parties have caused this Agreement to be executed
by their duly authorized representatives, with the intention of being legally
bound hereby.

[IXC INTERNET SERVICES]                   ("CORPORATION" NAME)

By:                                       By:
      (Signature)                               (Signature)
Name:                                     Name:
Title:                                    Title:
Date:                                     Date:


Master Teaming Agreement

Between IXC INTERNET SERVICES and ______________ dated___________________.









                          Schedule 2.1.3
                          Page 10 of 12

<PAGE>
                            EXHIBIT A

             FORM OF STATEMENT OF INTENT TO DEVELOP A PROPOSAL


Client:____________________________________________________________

Team Leader:_______________________________________________________

Team Member:_______________________________________________________

Request For Proposal Title/number (if applicable)__________________

Proposal Due Date (if applicable)__________________________________

DEVELOPMENT OF PROPOSAL. The parties agree to jointly develop a client proposal
under which each party would provide the respective products and services
generally and briefly described as follows:

___________________________________________________________________
___________________________________________________________________
___________________________________________________________________
___________________________________________________________________
___________________________________________________________________
___________________________________________________________________







                          Schedule 2.1.3
                          Page 11 of 12

<PAGE>
ACKNOWLEDGEMENT: This Statement of Intent To Develop A Proposal is issued
pursuant to the Master Teaming Agreement identified above. All of the terms and
conditions of the said Master Teaming Agreement are incorporated in and made a
part of this document as if expressly set forth herein.

IXC Internet Services                     ("Corporation" name)

By:                                       By:
Name:                               Name:
Title:                                    Title:




                          Schedule 2.1.3
                           Page 12 of 12

<PAGE>
                                 SCHEDULE 2.2

                            PSI SERVICE COMMITMENTS


1.    In providing Managed Connectivity Services under this Agreement, PSI
      will, at a minimum, comply with the following performance requirements:

      (a)   SERVICE AVAILABILITY. 24 x 7 (subject to scheduled downtime for
            network maintenance during low traffic periods, upon not less than
            one week notice, when possible, to IXC and affected IXC Customers).

      (b)   SERVICE RELIABILITY. 99.5%, excluding network problems (i)
            occurring between the customer's premise and the PSI
            Points-of-Presence, and (ii) occurring beyond the point where
            information exits the PSI backbone.

      (c)   INSTALLATIONS. Including acceptance and compliance with the minimum
            performance capabilities, PSI will complete as soon as practical
            but to occur no later than (i) 45 days after receipt of order by
            PSI and (ii) three business days following IXC or LEC provisioning
            of circuits pursuant to an assignment of customer addresses by
            InterNIC (which assignment will be requested promptly by PSI
            following receipt of order). In cases in which new circuits do not
            need to be provisioned in connection with a new installation, new
            customers may be given a shorter committed date for completion of
            installations.

      (d)   PROBLEM RESPONSIVENESS. The Parties will develop a mutually
            agreeable interface to the PSI trouble ticket system and
            appropriate problem escalation procedures to address the needs of
            IXC and IXC Customers.

{*}







*     Confidential material has  been omitted and filed separately with the
      Securities and Exchange Commission.




                           Schedule 2.2
                            Page 1 of 2

<PAGE>
      (a)   CLASS B ALLOCATION AND TRANSFER. Immediately upon execution of the
            Joint Marketing and Services Agreement to which this Schedule is
            attached (the "Marketing Agreement"), PSI will allocate a class
            B-sized block of address space, transfer all existing IXC (the PSI
            customer) addresses to it, and grant IXC all of PSI's right, title
            and interest in and to such class B address block. PSI will assist
            IXC in obtaining a class B from the InterNic (or other authority).
            At such time as such class B is allocated, IXC will transfer all of
            IXC's right, title and interest in and to such class B address
            block to PSI.

      (b)   INFRASTRUCTURE ENGINEERING. PSI will, at all times, treat the IXC
            class B as it would one of its own class B's for the purposes of
            routing, peering, and network throughput optimization.

3.    ANNOUNCEMENT. The services specified by IXC will be provided as a feature
      or function of the new PSI product/price plan for the ISP business
      market. Such plan is not completed. Upon completion, PSI will provide
      Internet routing for IXC and IXC customer networks via a separate AS
      number(s) assigned by appropriate Internet authorities. PSI will assist
      IXC in obtaining the necessary AS number(s), ownership of which is to be
      transferred and assigned to IXC. Notwithstanding the foregoing, PSI will
      obtain and implement updates to its ISP peering relationships and router
      configurations to allow full Internet routing for the IXC AS number(s)
      and associated networks at such time as PSI is able to do so.

4.    PEERING. PSI acknowledges that IXC reserves the right to establish its
      own peering relationships with other ISPs. PSI will work jointly with IXC
      to ensure appropriate routing for IXC between PSI and IXC borders.

5.    HARDWARE. PSI will make the equipment in Appendix 1 to this Schedule 2.2
      available for resale by IXC unless PSI is prevented from doing so by its
      contracts with the equipment suppliers. Should such supplier agreements
      prevent such resale, PSI will assist IXC in acquiring its own licenses to
      do so. The prices on Appendix 1 to this Schedule 2.2 may be changed to
      reflect the then PSI acquisition cost for such. Prices charged to IXC by
      PSI shall, however, be subject to the most favored pricing provisions of
      the Marketing Agreement.

6.    TERMS. PSI's obligations with respect to delivery of Services under the
      Marketing Agreement to an IXC Customer is, for all Services, subject to
      compliance by such IXC Customer, with the terms and conditions set forth
      in PSI's standard service agreements relating to the comparable services
      offered by PSI to PSI customers.

7.    COOPERATION. The Parties shall cooperate with each other to ensure that
      the product service descriptions, whether contained in the Documents,
      service agreements, world-wide web site pages or elsewhere, at all times
      fairly and accurately describe the features and functions of the
      Services.






                           Schedule 2.2
                           Page 2 of 2

<PAGE>
                          APPENDIX 1 TO SCHEDULE 2.2

                                  PSINET
                      INTRANET WAREHOUSE - HARDWARE LIST

PRODUCT NUMBER                DESCRIPTION                             PRICES
ROUTERS:
ascend-50            Ascend Pipeline 50 Router (with integrated NT1)  $   *
                     Compatible with LAN-ISDN

ascend-P130 Ascend Pipeline 130 Router (with integrated NT1               *
                     and T1 CSU/DSU)
                     Compatible with LAN-ISDN and interFrame 128K-T1
                     Services

cisco-2504  Cisco 2504 Router (TokenRing, v. 35, IP Only)                 *
                     Compatible with interFrame, InterPPP, and
                     LAN-ISDN (18 Channel)

cisco-2514  Cisco 2514 Dual Ethernet Router                               *
                     Compatible with InterFrame and InterPPP Services

comp-sys-900i        Compatible Systems MicroRouter 900i Single           *
                     Ethernet Router Compatible with LAN-DIAL, LAN-ISDN
                     (18 Channel),
                     InterPPP and InterFrame 56K Services

comp-sys-1220i       Compatible Systems MicroRouter 1220i Dual Ethernet   *
                     Router Compatible with LAN-DIAL, LAN-ISDN
                     (18 Channel),
                     InterPPP and InterFrame 56K-T1 Services

comp-sys-1220iV35    Compatible Systems MicroRouter 1220i Dual Ethernet   *
                     Router (with v.35 cable) 
                     Compatible with LAN-DIAL LAN-ISDN
                     (18 Channel),
                     InterPPP and InterFrame 56K bps-T1 Services

comp-sys-1270i       Compatible Systems MicroRouter 1270i Dual            *
                     Ethernet Router (with integrated T1 CSU/DSU)
                     Compatible with LAN-Dial, LAN-ISDN (18
                     Channel), and InterFrame 56K-T1 services

farallon-netop       Farallon Netopia 640 ISDN Router (with               *
640                  integrated NT1)
                     PC version for unlimited users. Compatible with
                     LAN-ISDN Service

farallon-netop       Farallon Netopia 440 ISDN Router (with               *
440                  integrated NT1)
                     Macintosh version for unlimited users.
                     Compatible with LAN-ISDN Service



*    Confidential material has been  omitted  and filed separately with the
     Securities and Exchange Commission




                    Appendix 1 to Schedule 2.2
                           Page 1 of 3

<PAGE>
PRODUCT NUMBER                DESCRIPTION                              PRICES

livingston-irx       Livingston IRX-211 Firewall Router (with             *
221                  v.35 cable)
                     Compatible with Interframe and InterPPP Services

protean-             Protean Globetrotter 60 (with v.35 cable)            *
globetrot 60         Compatible with Interframe Service

rockwell-nh-bri      Rockwell NetHopper NH-BRI 616 (with                  *
                     integrated NT1)
                     Includes internal analog modem. Compatible with
                     LAN-ISDN and LAN-DIAL Services.

MODEMS & CSU/DSUS:                                                        *
astro-nx1            Astrocom NX1 T1 CSU/DSU (Including sub-rate
                     T1)
                     Compatible with Interframe 128K-T1 Services

astro-2364  Astrocom 2364 56K CSU/DSU                                     *
                     Compatible with Interframe 56K and
                     InterPPP Services

usr-sportPC US Robotics Sportster 33.6 Kbps Modem                         *
                     PC version compatible with InterRamp and
                     LAN-DIAL Services

usr-sportMAC         US Robotics Sportster 33.6 Kbps Modem                *
                     Macintosh version compatible with InterRamp
                     and LAN-DIAL Services

MISCELLANEOUS:
3com-ImpactPC        3Com Impact (with external TA/NT1)                   *
                     PC version compatible with InnerRamp Service
                     via ISDN

3com-ImpactMAC       3Com Impact (with external TA/NT1)                   *
                     Macintosh version compatible with
                     InterRamp Service via ISDN

motorola-            Motorola Bitsurfer Pro (with external TA/NT1         *
                     and two bitsurfPC analog ports) PC
                     version compatible with LAN-ISDN and InterRamp
                     Service via ISDN.

motorola-            Motorola Bitsurfer PRO (with external TA/NT1         *
                     and bitsur MAC two analog ports)
                     Macintosh version compatible with LAN-ISDN and
                     InterRamp Service via ISDN.

nt-nt1               Northern TelecomTM Standalone NT1 Model A    
                     Includes 2 watt power supply. Compatible with       *
                     InterRamp and LAN-ISDN Services.



*    Confidential material has been omitted and  filed  separately with the
     Securities and Exchange Commission




                    Appendix 1 to Schedule 2.2
                          Page 2 of 3

<PAGE>
Note:       Continental U.S. Shipping:

Orders in Virginia must
includes a 4.5% sales tax.

                     Hardware: There is a [*] shipping fee for all
                     hardware purchased through PSINet.

Terms: Net 30 days.



*     Confidential material has been omitted and filed separately  with the
      Securities and Exchange Commission




                    Appendix 1 to Schedule 2.2
                        Page 3 of 3

<PAGE>

                  ATTACHMENTS TO SCHEDULE 2.2





                         REQUIREMENTS

                             FOR

                 MANAGED CONNECTIVITY SERVICES

                            AND

                      VALUE-ADDED SERVICES





<PAGE>
   DEDICATED INTERNET ACCESS SERVICE SERVICE REQUIREMENTS VERSION 1.1

1.    OVERVIEW

PSI's Dedicated Internet Access services provide full-time dedicated Internet
access via point-to-point 56K and T1 leased lines or SMDS metropolitan area
network T1 and T3 connections.

The PSI Dedicated Internet Access services include:

            o PSINet InterFrame
            o PSINet InterMAN

The PSI Dedicated Internet Access service specifications are included in
Schedule 2.3.

2.    WHOLESALE SERVICE BRANDING

PSI is to deliver the Dedicated Internet Access service to IXC and IXC
Customers on a branded basis, such that the service is delivered to the end
customer as an IXC or IXC Reseller branded service. Service branding is to be
present in the following areas:

            o        Sales collateral
            o        Service manuals and other service-related material.
            o        All PSI contact with the end customer, such as during
                     order verification, service provisioning, and customer
                     support
            o        Email addresses and web site domain names for customer
                     support, service status, service information.
            o        Service usage reports

Where additional investment and resources are required, PSI will state
estimated costs in advance for which IXC or the IXC Reseller is responsible.

3.    DELIVERY PROCESSES

Documented delivery processes are to be developed by PSI. PSI will work to
integrate internal processes with IXC's service processes, specifically in the
areas of:

            o        Sales support
            o        Order processing
            o        Service provisioning
            o        Customer support
            o        Network operation procedures and escalation
            o        Trouble ticketing and tracking
            o        Billing

PSI must create and maintain delivery process documentation specific to the
items listed above.

4.    SERVICE IMPLEMENTATION

IXC is responsible for:

            o        Submitting accurate and correct service order information
                     to PSI

PSI is responsible for:





                    Attachments to Schedule 2.2
                         Page 1 of 34

<PAGE>
            o        Via IXC, ordering, installing, and configuring the
                     customer's communications circuit
            o        Internet service provisioning and configuration (IP
                     addresses, DNS, routing, etc.) for the customer's network
                     o Registration and assignment of IP address numbers
            o        Registration of the customer's domain name
            o        Implementation of routing information as required for the
                     customer's environment.

PSI's installation technicians are responsible for remotely assisting the
customer's technical liaison in the physical installation of the customer
premise equipment (CPE).

Service implementation details are described below.

4.1.    SITE PLANNING AND PREPARATION COORDINATION

Site planning coordination will be provided by PSI to the customer's designated
point of contact. This helps customers to prepare for installation of the
Dedicated Internet Access service. Customers need to provide space and power
for the CPE equipment, an attachment to the customer's internal network, and at
least one computer with TCP/IP support.

4.2.        COMMUNICATIONS CIRCUIT ORDERING

PSI is responsible for ordering (from IXC, on behalf of the customer) and
maintaining the communications circuit necessary for delivery of service. IXC
will either provide the circuit itself or order one from another
telecommunications vendor and at IXC's cost.

4.2.1.      INSIDE WIRING

PSI arranges for IXC to terminate the circuit in proximity to the planned
location of the premises equipment. Any cost associated with extending the
circuit to this location (inside wiring) is passed on to the customer.

4.3.        CUSTOMER PREMISE EQUIPMENT

The customer premises equipment package consists of a TCP/IP router with
appropriate LAN and WAN interfaces, a CSU/DSU corresponding to the connection
type, and associated cables.

4.3.1.      SUPPORTED CUSTOMER PREMISE EQUIPMENT

PSI will only support CPE that has been tested by PSI and certified for
compatibility with PSI services. PSI will maintain a current WWW list of
certified and supported CPE.

4.3.2.      CUSTOMER PREMISE EQUIPMENT PROVISIONING

Managed services (E.G., InterMAN, InterFrame with RouteWaller) require that the
CPE be owned and operated by PSI. When the customer prefers to own and operate
their own equipment, CPE may be purchased through PSI. When purchased through
PSI, the package of service equipment utilized by each customer is to be
pre-assembled by PSI and subjected to a hardware quality acceptance test by PSI
before delivery to the customer site. Equipment not purchased through PSI is
subject to verification of suitability by PSI. PSI will consider non-certified
routers on a case-by-case basis.





                    Attachments to Schedule 2.2
                      Page 2 of 34

<PAGE>
Customers providing their own premises equipment must maintain the premises
equipment to current hardware and software revision levels for compatibility
with the PSI service.

4.4.        CUSTOMER PPREMISE EQUIPMENT STAGING AND CONFIGURATION

To ease installation, equipment is to be either pre-configured by PSI before
delivery to the IXC customer site or PSI assists in remotely configuring after
it is connected to the network.

For customer premise equipment supplied by PSI, PSI is responsible for
pre-configuring the customer premise equipment with its initial configuration
information prior to shipping to the IXC customer site.

When the IXC customer supplies the premise equipment, PSI is responsible for
providing to the customer initial configuration information for the customer
premise equipment sufficient to enable IP connectivity to the customer's
network.

4.5.        CUSTOMER PREMISE EQUIPMENT INSTALLATION

PSI's installation technicians are responsible for remotely assisting the IXC
customer's technical liaison in the installation of the premises equipment. The
customer's technical liaison performs the physical installation of the premises
equipment. On-site CPE installation by a PSI field technician or agent is to be
provided by PSI on an optional basis (InterFrame) unless otherwise specified in
the service specification (InterMAN). Please see attached price sheet.

4.6.        IPADDRESS ALLOCATION

*


*

4.7.IP ROUTING SERVICE

4.7.1.      IP ROUTING FOR IXC CUSTOMERS

PSI must perform any IP routing configuration changes to its network routers
necessary to enable Internet routing for IP traffic destined to or received
from the IXC customer's network.

*

4.8.        DOMAIN NAME SERVICE (DNS)

PSI is to provide IXC Dedicated Internet Access customers with primary and/or
secondary domain name service as necessary for successful presence on the
Internet.

4.8.1.      DOMAIN NAME REGISTRATION

On behalf of IXC customers, PSI is to perform registration of the customers'
domains with the InterNIC and/or its successors. PSI is to submit domain name
registrations to the InterNIC using registration and billing information
provided to PSI by IXC or the IXC Reseller as part of the customer order.
InterNIC or its


*     Confidential material has been omitted and filed separately with  the
      Seurities and Exchange Commission




                    Attachments to Schedule 2.2
                       Page 3 of 34

<PAGE>
successor(s) will invoice the IXC customer directly for the domain name
registered.

For existing customer domains, PSI is responsible for assisting IXC customers
with the transfer of existing domain name service to the PSI nameservers, using
processes designed to minimize any discontinuity of Domain Name Service for the
customer's domains.

4.8.2.       DOMAIN NAME SERVICE OPERATION

DNS service provided to IXC customers by PSI must be maintained on multiple
nameservers which are physically diverse and connected to the PSI backbone at
different points.

IXC customers may elect to run and administer their own primary and/or
secondary nameservers. For customers running their own primary nameserver, PSI
is to offer secondary nameservice for the customer's domains on at least two
PSI nameservers.

Nameservice for one domain per customer connection is part of the basic
service. Nameservice for additional domains is available as an option. Please
see attached fee schedule.

4.8.3.      DNS UPDATES

For IXC customer domains for which PSI provides primary nameservice, PSI must
perform updates to the customer domain zone information as reasonably requested
by the customer. Zone update procedures are to be documented by PSI and
provided to IXC. PSI is to provide a web interface as soon as possible that
allows IXC customers to make changes to their domain information interactively.

Turnaround time for updated IXC customer DNS information to be available on the
Internet via Internet accessible PSI nameservers must be no more than 24 hours.

4.9.        ACCEPTANCE TESTING

PSI is to conduct ping test to the customer's site to ensure that the customer
premise router can successfully communicate over the IXC Dedicated Internet
Access service and service billing by PSI to IXC may be initiated. Additional
tests will be performed thereafter to verify the proper operation of the
on-site equipment package, the local access facility, and the PSI Internet
infrastructure, including IP routing, DNS, Usenet news, and other services.

4.10.       ACCEPTANCE CRITERIA.

PSI implementation of service for IXC Dedicated Internet Access service
customers is considered complete when the following criteria have been met:

4.10.1.      A circuit has been installed and configured to give the customer
the amount of bandwidth contracted for between the customer location and the
PSI Point-of-Presence (POP). If a Frame Relay connection, PVCs have been
configured with appropriate CIR and burst values as contracted for by the
customer.

4.10.2.     The Dedicated Internet Access router and associated premises
equipment is installed at the customer site, and IP connectivity between the
customer network and the Internet (including routing outside PSI networks)
exists.

PSI must verify IP connectivity through a test which:

            o        sends repeated pings through the Internet to the customer
                     site and verifies that the pings were received.




                    Attachments to Schedule 2.2
                         Page 4 of 34

<PAGE>
            o        in cases when the premises equipment configuration
                     supports it, PSI must verify IP routing through a trace
                     route test.

4.10.3.     IP addresses have been allocated from IXC's address space to the
customer for use on their network.

4.10.4.     Any necessary routing changes have been made in PSI's network
routers so that routes to the customers IP networks and addresses are announced
to the Internet.

4.10.5.     For customers with their own domain, the domain is registered with
the InterNIC and any PSI-supplied primary and secondary DNS servers are
operational for it.

4.10.6.     Any initial customer requested packet-filtering option has been
installed in the customer premise Dedicated Internet Access router.

4.10.7.     The customer has been informed that the Internet service is
available for implementation of Internet application such as, Telnet, FTP,
E-Mail or WWW, and has acknowledged that they plan to configure these
applications within the installation phase or that they do not intend to at
this time. Billing will commence upon a successful ping test and not acceptance
of working Internet application.

4.10.8.     The customer has been informed of the operational status of the
customer's Internet connection and been provided with documentation of (i) the
Internet service configuration, and (ii) the acceptance test results.

4.10.9.     IXC has been informed of the operational status of the customer's
Internet connection and been provided with documentation of (i) the Internet
service configuration, and (ii) the acceptance test results.

4.10.10.    The IXC customer has been given an information package designed for
new Dedicated Internet Access customers.

5.          SERVICE OPTIONS

5.1.        USENET NEWS SERVICE

IXC offers NNTP news feeds and/or NNRP news server access to its Dedicated
Access Internet Service customers. PSI is responsible for working with the IXC
customer to determine whether the size of the customer's Internet access line
is sufficient to meet the customer's network news requirements. PSI is to
provide the IXC customer with Usenet News access via an NNTP news feed from
PSI's news servers to the customer's news server, or alternately by allowing
the IXC customer to directly access PSI's news server with client software
using the NNRP protocol.

Please see fee schedule for pricing.

 5.1.1.     NNTP NEWS FEED

As a prerequisite to receiving a Usenet News Feed, the IXC customer must
install a news server. PSI is responsible for assisting the IXC customer in
determining the news feed parameters.

Once the server is in place and the service is established, PSI is to maintain
the news feeds for all IXC customers receiving NNTP news feeds.

PSI's news servers are to accept news postings from the customer's news server
and propagate these postings on to other Usenet news servers on the Internet.




                    Attachments to Schedule 2.2
                         Page 5 of 34

<PAGE>
IXC customers may request changes to the list of news groups fed from PSI's
news servers, during normal business hours and at a frequency averaging up to
one change request per week. PSI is responsible for implementing the required
changes on the PSI news servers within 24 hours.

Please see fee schedule for pricing.

5.1.2.      NNRP NEWS ACCESS

The IXC Dedicated Access Internet Service customer may chose not to run a news
server on their network and instead request NNRP access to PSI's news servers
as a client. PSI must provide NNRP access to the IXC Dedicated Access Internet
Service customer for up to 25 newsreader clients. PSI's news servers are to
accept Usenet news postings from the customer's NNRP clients and propagate
these postings on to other Usenet news servers on the Internet.

Please see fee schedule for pricing.

5.2.        NETWORK USAGE STATISTICS REPORTING

PSI is responsible for providing Network Usage Statistics Reporting to IXC
Dedicated Internet Access service customers. Network Usage Statistics Reports
are to be traffic summary reports that allow customers to track access line
utilization and peak activity periods.
The usage report must be produced on a regular basis (daily, weekly, and
monthly) and is to be provided to the customer and to IXC via email and the
Web.

The usage information is to be collected from the customer premises and other
network equipment using SNMP and other measurement tools.

Please see fee schedule for pricing.

5.3.        EMERGENCY BACKUP SERVICE

In the event of a failure in connectivity between the customer's location and
the PSI Point-of-Presence (POP) due to POP equipment failure or failure of the
circuit connecting the customer location to the PSI POP, PSI must provide to
the customer a PSI dial-up packet access point within four hours after
disruption of service (except as provided in Section 15.2 of the Marketing
Agreement). This service option must be requested and set up in advance of an
event.

6.          NETWORK OPERATIONS SUPPORT

PSI's is responsible for network operations support for network services
provided to IXC Dedicated Internet Access service as described in this section.

6.1.        PSI INFRASTRUCTURE OPERATIONS SUPPORT

PSI must monitor the PSI network 24 hours a day, 365 days a year. PSI is to
provide proactive operations support and troubleshooting of all network and
service infrastructure components providing service to IXC customers, including
IXC-provided circuits (such as circuits from the PSI POP to the customer
premise).

PSI will use SNMP and other software tools to monitor the network. This
software must be supplemented with additional tools to monitor non- SNMP
equipment, domain name servers, NNTP news servers and feeds, and other network
services.

All network services (routing, DNS, email servers, Usenet news, NTP, security,
etc.) must be monitored for availability and performance. The monitoring
software




                    Attachments to Schedule 2.2
                          Page 6 of 34

<PAGE>
must report the status of the network to a display which is monitored
throughout the day.

Service outages are to be automatically detected. Troubleshooting procedures
and customer notification will occur within * of an outage.

IXC and PSI will work jointly on resolution procedures.

6.1.1       NETWORK REPORTS

PSI is to provide IXC with network status logs on a regular basis to provide
IXC with the ability to evaluate staff responsiveness and network availability.
All changes in the PSI network status must be logged.

PSI is to provide IXC with regular reports on the status of the PSI network.
Report information is to be defined by IXC, and will include but not be limited
to:

*

6.2         CUSTOMER CONNECTIVITY SUPPORT

PSI must monitor IXC customers' connectivity to ensure continuous Internet
connectivity is provided to the customer network. IXC Dedicated Internet Access
customer connectivity outages must be detected by PSI and acted upon by PSI
within * .

PSI must follow up on loss of connectivity using documented trouble resolution
procedures as jointly developed by IXC and PSI.

6.3         COMMUNICATIONS LINK MAINTENANCE

PSI is responsible for monitoring and maintaining the communications link
between the Customer and PSI. This includes problem diagnosis and any necessary
vendor interaction for dispatch and repair. PSI's staff is to escalate
communications circuit problems using documented trouble resolution procedures
as jointly developed by IXC and PSI.

6.4         CUSTOMER PREMISES EQUIPMENT MAINTENANCE FOR INTERMAN

If the customer has contracted for customer premise Internet router and CSU/DSU
maintenance, PSI is responsible for maintaining the customer premise equipment.
PSI must diagnose failures, usually with the assistance of the technical
liaison designated by the customer at the site, and shall determine whether
equipment replacement is required.

6.4.1       ON-SITE CPE REPAIR / REPLACEMENT FOR INTERMAN



*     Confidential  material has been omitted and filed separately with the
      Securities and Exchange Commission






                    Attachments to Schedule 2.2
                          Page 7 of 34

<PAGE>
PSI is responsible for performing the actual equipment replacement with
telephone assistance (as necessary).

Response time for performing customer premise equipment replacement must meet
the schedule described within the PSI customer maintenance contract.

7.          TECHNICAL SERVICES AND CUSTOMER SUPPORT

IXC is to provide first level customer support for all IXC Dedicated Access
Internet customers.

7.1         STANDARD SERVICE CUSTOMER SUPPORT HELPLINE

PSI must staff an IXC Customer Support helpline with trained and qualified PSI
customer support representatives from 8am-8pm EST/EDT Monday through Friday.
Customer support staff must be trained in supporting Dedicated Internet Access
service customers. Additionally, an outage support hotline (Netwatch) shall be
staffed 24 hours per day, 7 days per week, 365 days per year for network access
emergency reporting to IXC and its customers.

7.1.1       CUSTOMER SUPPORT HELPLINE RESPONSE TIME

Calls to the PSI-provided IXC customer support hotline must be answered within
* rings., 8am-8pm EST/EDT Monday through Friday. For similar response times
off-hours, optional support may be available (at additional cost).

7.2         CUSTOMER SUPPORT EMAIL MAILBOX SEE SECTION 7.4.

7.3         FAULT ISOLATION AND PROBLEM RESOLUTION

PSI is to perform fault isolation for problems related to the PSI provided
service. Fault isolation may involve coordination among network operators and
technicians, staff at the affected site, telecommunications carriers, and other
vendors. Depending on the specific technologies used, the process may involve
testing equipment, reconfiguring routers, or diagnosing communications link
problems. PSI is responsible for diagnosing service problems and tracking
repair progress. PSI is to use documented trouble resolution procedures as
jointly developed and agreed upon by PSI and IXC.

7.4         TROUBLE TICKETING SYSTEM

PSI must use a Trouble Ticketing System to track problems from initial report
through satisfactory resolution. As PSI staff works to resolve problems, the
current status must be maintained in the Trouble Ticketing System.

7.4.1       IXC CUSTOMER ACCESS TO TROUBLE TICKETING SYSTEM

IXC customers will be provided access by PSI to any trouble tickets related to
their service, as soon as the technology is available to PSI. If additional
programming is required to deliver this functionality, it will be costed out
and provided to IXC in advance. The trouble ticketing system should provide
designated customer contacts with automatic access to the trouble tickets via
web interfaces.



*     Confidential material has been  omitted and filed separately with the
      Securities and Exchange Commission.




                    Attachments to Schedule 2.2
                        Page 8 of 34

<PAGE>
PSI Backbone status information should also be made available to IXC Customer
contacts requesting same via the same interfaces.

7.4.2       IXC RESELLER ACCESS TO TROUBLE TICKETING SYSTEM

IXC resellers will be provided access by PSI to any trouble tickets related to
the service, as soon as the technology is available to PSI. If additional
programming is required to deliver this functionality, it will be costed out
and provided to IXC in advance. The trouble ticketing system should provide
designated IXC Reseller contacts with automatic access to the trouble tickets
via web interfaces.

PSI Backbone status information should also be made available to IXC Reseller
contacts requesting same via the same interfaces.

7.4.3       IXC ACCESS TO TROUBLE TICKETING SYSTEM

IXC will be provided access by PSI to any trouble tickets related to the
service provided to IXC, IXC Resellers and their end customers, as soon as the
technology is available to PSI. If additional programming is required to
deliver this functionality, it will be costed out and provided to IXC in
advance. The trouble ticketing system should provide designated IXC contacts
with automatic access to the trouble tickets via web interfaces.

PSI Backbone status information should also be made available to IXC Reseller
contacts requesting same via the same interfaces.

PSI is to work with IXC to integrate trouble ticketing systems and processes as
much as reasonably possible.

7.5         PROBLEM NOTIFICATION

7.5.1       IXC CUSTOMER PROBLEM NOTIFICATION

The PSI operations staff must inform the technical contact of IXC Dedicated
Internet Access service customers of any outages affecting their service. The
operations staff must also keep Dedicated Internet Access customers informed of
any widespread outages on connecting networks.


7.5.2       IXC RESELLER PROBLEM NOTIFICATION

The PSI operations staff must inform the technical contact of IXC Resellers of
any outages affecting service to their end customers. The operations staff must
also keep IXC Resellers informed of any widespread outages on connecting
networks.

7.5.3       IXC PROBLEM NOTIFICATION

The PSI operations staff must inform the IXC technical contacts of any outages
affecting service to IXC, IXC Resellers, or IXC end customers. The operations
staff must also keep IXC informed of any widespread outages on connecting
networks.

7.6         SOFTWARE AND CONFIGURATION SUPPORT FOR INTERMAN

PSI is responsible for coordinating software updates and configuration changes
on the customer premise router and CSU/DSU equipment of IXC customers as
required to provide Internet service. Notice of software changes is to be made
to the customer technical contacts, and every effort must be made to perform
maintenance during off-hours.




                    Attachments to Schedule 2.2
                       Page 9 of 34

<PAGE>
7.7         ESCALATION PROCEDURES

Documented customer support processes are to be developed jointly by PSI and
IXC. Specific process documentation is required for the following:

            o        customer support procedures
            o        trouble escalation procedures
            o        trouble ticketing, tracking, and resolution

PSI must provide information to the IXC customer describing customer support,
problem resolution, and trouble escalation procedures, customer contact
information, and trouble reporting methods.

8.          SECURITY PROCEDURES

The following services provide security procedures: RouteWaller (InterFrame),
SecureEnterprise (InterFrame and InterMAN), and PSI IntraNet.

Additionally, PSI's Net Abuse policy shall apply to all IXC customers.





                    Attachments to Schedule 2.2
                             Page 10 of 34

<PAGE>

SWITCHED LAN INTERNET ACCESS SERVICE SERVICE REQUIREMENTS VERSION 1.1

1.          OVERVIEW

PSI's Switched LAN Internet Access services provide on-demand switched
connectivity to the Internet via an analog modem (9.6 - 33.6 Kbps) or an ISDN
NT1 (64 - 128 Kbps) and a customer premise router. Connectivity is provided to
the customer's LAN rather than a single system, via the customer premise
router. Connections are established between the customer premise and an PSI
Point-of-Presence (POP) using the Point-to-Point Protocol (PPP).

The PSI Switched LAN Internet Access services include:

            o        PSINet LAN-On-Demand (LAN-Dial and LAN-ISDN)

The PSI Switched LAN Internet Access service specification is included in
Schedule 2.3.

2.          WHOLESALE SERVICE BRANDING

PSI is to deliver the Switched LAN Internet Access service to IXC and IXC
Customers on a branded basis, such that the service is delivered to the end
customer as an IXC or IXC Reseller branded service. Service branding is to be
present in the following areas:

            o        Sales collateral
            o        Service manuals and other service-related material.
            o        All PSI contact with the end customer, such as during
                     order verification, service provisioning, and customer
                     support
            o        Email addresses and web site domain names for customer
                     support, service status, service information. o Service
                     usage reports

Where additional investment and resources are required, PSI will state
estimated costs in advance for which IXC or the IXC reseller is responsible.

3.          DELIVERY PROCESSES

Documented delivery processes are to be developed by PSI. PSI must work to
integrate internal processes with IXC's service processes, specifically in the
areas of:

            o        sales support
            o        order processing
            o        service provisioning
            o        customer support
            o        network operation procedures and escalation
            o        trouble ticketing and tracking
            o        billing

PSI must create and maintain delivery process documentation specific to the
items listed above.

4.          SERVICE IMPLEMENTATION

PSI is responsible for providing and maintaining dial-up Points-of-Presence
(POPs) with analog modem and ISDN access capability that allow local switched




                    Attachments to Schedule 2.2
                           Page 11 of 34

<PAGE>
access from the customer location. PSI will provide modem ports via dial-up
access numbers for IXC Switched LAN Internet Access Service customers.

IXC is responsible for:

            o        Submitting accurate and correct service order information
to PSI

PSI is responsible for:

            o        Internet service provisioning and configuration ( * , DNS,
                     routing, etc.) for the customer's network

*

            o Registration of the customer's domain name

            o        Implementation of routing information as required for the
                     customer's environment.

PSI is responsible for remotely assisting the customer's technical liaison in
the physical installation of the customer premise equipment (CPE).

Implementation support details are described below.

4.1.        SITE PLANNING AND PREPARATION COORDINATION

Site planning coordination must be provided by PSI to the customer's designated
point of contact. This helps customers to prepare for installation of the
Switched LAN Internet Access service. Customers need to provide space and power
for the CPE equipment, an attachment to the customer's internal network, and at
least one computer with TCP/IP support.

4.2.        COMMUNICATIONS CIRCUIT ORDERING

The customer is responsible for ordering and having installed an analog phone
line or an ISDN line to support the service at its sole cost.

The customer should arrange for the circuit to terminate in proximity to the
planned location of the premises equipment. Any cost associated with extending
the circuit to the planned location of the premises equipment (inside wiring)
is the responsibility of customer.

4.3.        CUSTOMER PREMISE EQUIPMENT

The customer premise equipment package consists of a TCP/IP router with
appropriate LAN and WAN interfaces, an analog modem or ISDN NT1 device, and
associated cables.

4.3.1.      SUPPORTED CUSTOMER PREMISE EQUIPMENT

PSI will only support CPE that has been tested by PSI and certified for
compatibility with PSI services. PSI will maintain a current WWW list of
certified and supported CPE.



*    Confidential material has been omitted  and  filed separately with the
     Securities and Exchange Commission.




                    Attachments to Schedule 2.2
                          Page 12  of 34

<PAGE>
4.3.2.      CUSTOMER PREMISE EQUIPMENT PROVISIONING

The customer premise equipment may be purchased through PSI. When purchased
through PSI, the package of service equipment utilized by each customer is to
be pre-assembled by PSI and subjected to a hardware quality acceptance test by
PSI before delivery to the customer site. Equipment not purchased through PSI
is subject to verification of suitability by PSI.

Customers providing their own premises equipment must maintain the premises
equipment to current hardware and software revision levels for compatibility
with the PSI service.

4.4.        EQUIPMENT STAGING AND CONFIGURATION

For customer premise equipment supplied by PSI, PSI is responsible for
pre-configuring the customer premise equipment with its initial configuration
information prior to shipping to the IXC customer site.

When the IXC customer supplies the premise equipment, PSI is responsible for
providing to the customer initial configuration information for the customer
premise equipment sufficient to enable IP connectivity to the customer's
network.

4.5.        CUSTOMER PREMISE EQUIPMENT INSTALLATION - NOT APPLICABLE

4.6.        CUSTOMER PREMISE EQUIPMENT

PSI is responsible for remotely assisting the IXC customer's technical liaison
in the installation of the premises equipment. The customer's technical liaison
performs the physical installation of the premises equipment.

*

PSI is responsible for maintaining a record of all IP address allocations for
each IXC customer. PSI is to provide this information to IXC on a regular
basis.

4.8.        IP ROUTING SERVICE

PSI must perform any IP routing configuration changes to its network routers
necessary to enable Internet routing for IP traffic destined to or received
from the IXC customer's network.

4.8.1.      ROUTING SERVICE FOR MULTIPLE CONNECTED NETWORKS

BGP routing is not available to IXC Switched LAN Internet Access customers.

4.9.         DOMAIN NAME SERVICE (DNS)

PSI is to provide IXC Switched LAN Internet Access customers with primary
and/or secondary domain name service as necessary for successful presence on
the Internet.

4.9.1.      DOMAIN NAME REGISTRATION

On behalf of IXC customers, PSI is to perform registration of the customers'
domains with the InterNIC and/or its successors. PSI is to submit domain name


*     Confidential material has been omitted and filed  separately with the
      Securies and Exchange Commission.




                    Attachments to Schedule 2.2
                       Page 13 of 34

<PAGE>
registrations to the InterNIC using registration and billing information
provided to PSI by IXC or the IXC Reseller as part of the customer order.

For existing customer domains, PSI is responsible for assisting IXC customers
with the transfer of existing domain name service to the PSI nameservers, using
processes designed to minimize any discontinuity of Domain Name Service for the
customer's domains. InterNIC or its successor(s) will invoice the IXC customer
directly for the domain name registered.

For IXC customer domains for which PSI is to operate the primary nameserver,
PSI is to register with the InterNIC only the secondary nameservers. This is to
ensure that DNS lookups are not affected during rebooting of the primary
nameserver.

4.9.2.       DOMAIN NAME SERVICE OPERATION.

DNS service provided to IXC customers by PSI must be maintained on multiple
nameservers which are physically diverse and connected to the PSI backbone at
different points.

IXC customers may elect to run and administer their own primary and/or
secondary nameservers. For customers running their own primary nameserver, PSI
is to offer secondary nameservice for the customer's domains on at least two
PSI nameservers. Nameservice for one domain per customer connection is part of
the basic service. Nameservice for additional domains is available as an
option. Please see attached fee schedule.

4.9.3.      DNS UPDATES

For IXC customer domains for which PSI provides primary nameservice, PSI must
perform updates to the customer domain zone information as reasonably requested
by the customer. Zone update procedures are to be documented by PSI and
provided to IXC. PSI is to provide a web interface as soon as possible that
allows IXC customers to make changes to their domain information interactively.

Turnaround time for updated IXC customer DNS information to be available on the
Internet via Internet accessible PSI nameservers must be no more than 24 hours.

4.10.       ACCEPTANCE TESTING

PSI is to conduct tests to the customer's site to ensure that the customer
premise router can successfully communicate over the IXC Switched LAN Internet
Access service. Service billing will commence seven business days after account
creation by PSI. Additional tests will be performed thereafter to verify the
proper operation of the on-site equipment package, the local access facility,
and the PSI Internet infrastructure, including IP routing, DNS, Usenet news,
and other services.

4.11.        ACCEPTANCE CRITERIA

PSI implementation of service for IXC Switched LAN Internet Access service
customers is considered complete when the following criteria have been met:

4.11.1.     A dial-in port matching the customer's contract port type and speed
is available to the customer at the local IXC Point-of-Presence (POP).

4.11.2.     The customer is able to successfully establish a PPP connection

4.11.3.     The Switched LAN Internet Access router and associated premises
equipment is installed at the customer site, and IP connectivity between the




                    Attachments to Schedule 2.2
                        Page 14 of 34

<PAGE>
customer network and the Internet (including routing outside PSI networks)
exists. PSI must verify IP connectivity through a test which:

(a)         sends repeated pings through the Internet to the customer site and
verifies that the pings were received.

(b)         in cases when the premises equipment configuration supports it, PSI
must verify IP routing through a traceroute test.

*

(d)         Any necessary routing changes have been made in PSI's network
routers so that routes to the customers IP networks and addresses are announced
to the Internet.

(e)         For customers with their own domain, the domain is registered with
the InterNIC and any PSI-supplied primary and secondary DNS servers are
operational for it.

(f)         Any initial customer requested packet-filtering has been installed
in the customer premise Switched LAN Internet Access router.

(g)         The customer has been informed that the Internet service is
available from implementation of Internet application such as, Telnet, FTP,
E-Mail or WWW, and has acknowledged that they plan to configure these
applications within the installation phase or that they do not intend to at
this time. Billing will commence upon a successful ping test and not acceptance
of working Internet application.

(h)         The customer has been informed of the operational status of the
customer's Internet connection and been provided with documentation of (i) the
Internet service configuration, and (ii) the acceptance test results.

(i)         IXC has been informed of the operational status of the customer's
Internet connection and been provided with documentation of (i) the Internet
service configuration, and (ii) the acceptance test results.

(j) The IXC customer has been given an information package designed for new
Switched LAN Internet Access customers.

5.          SERVICE OPTIONS

5.1.        USENET NEWS SERVICE

5.2.        USENET NEWS

IXC offers NNRP news server access to its Switched LAN Internet Access Service
customers. PSI is responsible for working with the IXC customer to determine
whether the size of the customer's Internet access line is sufficient to meet
the customer's network news requirements. PSI is to provide the IXC customer
with Usenet News access by allowing the IXC customer to directly access PSI's
news server with client software using the NNRP protocol.

Please see fee schedule for pricing.



*     Confidential material has been omitted and filed separately  with the
      Securities and Exchange Commission.




                    Attachments to Schedule 2.2
                         Page 15 of 34

<PAGE>
5.2.1.      NNTP NEWS FEED

NNTP news feeds are not available to Switched LAN Internet Access service
customers.

5.2.2.      NNRP NEWS ACCESS

NNRP access is be provided by PSI to IXC's Switched LAN Internet Access service
customers. PSI must provide NNRP access to the IXC Dedicated Access Internet
Service customer for up to 25 newsreader clients. PSI's news servers are to
accept Usenet news postings from the customer's NNRP clients and propagate
these postings on to other Usenet news servers on the Internet

Please see fee schedule for pricing.

5.2         NETWORK USAGE STATISTICS REPORTING

PSI is responsible for providing Network Usage Statistics Reporting to IXC
Switched LAN Internet Access service customers. Network Usage Statistics
Reports are to be traffic summary reports that allow customers to track access
line utilization and peak activity periods.

The usage report must be produced on a regular basis (daily, weekly, and
monthly) and is to be provided to the customer and to IXC via email and the
Web.

The usage information is to be collected from the customer premises and other
network equipment using SNMP and other measurement tools.

Please see fee schedule for pricing.

5.3.        EMERGENCY BACKUP SERVICE

In the event of a failure in connectivity between the customer's location and
the PSI Point-of-Presence (POP) due to POP equipment failure ) then the
customer may use a different dialup POP.

6.          NETWORK OPERATIONS SUPPORT

PSI is responsible for network operations support for network services provided
to IXC Switched LAN Internet Access service as described in this section.

6.1.        PSI INFRASTRUCTURE OPERATIONS SUPPORT

PSI must monitor the PSI network 24 hours a day, 365 days a year. PSI is to
provide proactive operations support and troubleshooting of all network and
service infrastructure components providing service to IXC customers, including
IXC-provided circuits (such as circuits from the PSI POP to the customer
premise).

PSI is to use SNMP and other software to monitor the network. This software
must be supplemented with additional tools to monitor non-SNMP equipment,
domain name servers, NNTP news servers and feeds, and other network services.

All network services (routing, DNS, email servers, Usenet news, NTP, security,
etc.) must be monitored for availability and performance. The monitoring
software must report the status of the network to a display which is monitored
throughout the day.





                    Attachments to Schedule 2.2
                        Page 16 of 34

<PAGE>
Service outages are to be automatically detected within * and acted upon using
trouble resolution procedures agreed upon by PSI and IXC.

6.1.1.               NETWORK REPORTS

PSI is to provide IXC with network status logs on a regular basis to provide
IXC with the ability to evaluate staff responsiveness and network availability.
All changes in the PSI network status must be logged.

PSI is to provide IXC with regular reports on the status of the PSI network.
Report information is to be defined by IXC, and will include but not be limited
to:



*

 Please see example attached.

6.2.        CUSTOMER CONNECTIVITY SUPPORT

PSI must monitor PSI's connectivity to ensure continuous Internet connectivity
is available to the customer network. Outages affecting IXC Switched LAN
Internet Access customer connectivity outages must be detected by PSI and acted
upon by PSI within * .

PSI staff must follow up on loss of connectivity using documented trouble
resolution procedures as jointly developed by IXC and PSI.

6.3.        COMMUNICATIONS LINK MAINTENANCE

PSI is responsible for monitoring the backbone and POP equipment. This includes
problem diagnosis and any necessary vendor interaction for dispatch and repair.
PSI's staff is to escalate communications circuit problems using documented
trouble resolution procedures as jointly developed by IXC and PSI.

7.          TECHNICAL SERVICES AND CUSTOMER SUPPORT

IXC is to provide first level customer support for all IXC Switched LAN
Internet Access customers.

7.1.         24-HOUR CUSTOMER SUPPORT HELPLINE

PSI must staff an IXC Customer Support helpline with trained and qualified PSI
customer support representatives from 8am-8pm EST/EDT Monday through Friday.
Customer support staff must be trained in supporting Dedicated Internet Access
service customers. Additionally, an outage support hotline (Netwatch) shall be
staffed 24 hours per day, 7 days per week, 365 days per year for network access
emergency reporting to IXC and its customers.


*    Confidential  material has been omitted and filed separately with  the
     Securities and Exchange Commission





                    Attachments to Schedule 2.2
                         Page 17 of 34

<PAGE>
7.1.1.      CUSTOMER SUPPORT HELPLINE RESPONSE TIME

Calls to the PSI-provided IXC customer support hotline must be answered within
*  rings., 8am-8pm EST/EDT Monday through Friday. For similar response times
off-hours, optional support may be available (at additional cost).

7.2.        CUSTOMER SUPPORT EMAIL MAILBOX

See section 7.4.

7.3.        FAULT ISOLATION AND PROBLEM RESOLUTION

PSI is to perform fault isolation for problems related to the PSI provided
service.  Fault isolation may involve coordination among network operators and
technicians, staff at the affected site, telecommunications carriers, and other
vendors. Depending on the specific technologies used, the process may involve
testing equipment, reconfiguring routers, or diagnosing communications link
problems. The PSI operations staff is responsible for diagnosing service
problems and tracking repair progress. PSI is to use documented trouble
resolution procedures as jointly developed and agreed upon by PSI and IXC.

7.4.        TROUBLE TICKETING SYSTEM

PSI must use a Trouble Ticketing System to track problems from initial report
through satisfactory resolution. As PSI staff works to resolve problems, the
current status must be maintained in the Trouble Ticketing System.

7.4.1.       IXC CUSTOMER ACCESS TO TROUBLE TICKETING SYSTEM

IXC customers must be provided access by PSI to any trouble tickets related to
their service, as soon as the technology is available to PSI. If additional
programming is required to deliver this functionality, it will be costed out
and provided to IXC in advance. The trouble ticketing system should provide
designated customer contacts with automatic access to the trouble tickets via
web interfaces.

PSI Backbone status information must also be made available to IXC customer
contacts requesting same via the same interfaces.

7.4.2.      IXC RESELLER ACCESS TO TROUBLE TICKETING SYSTEM

IXC resellers must be provided access by PSI to any trouble tickets related to
the service provide to their end customers, as soon as the technology is
available to PSI. If additional programming is required to deliver this
functionality, it will be costed out and provided to IXC in advance.. The
trouble ticketing system should provide designated IXC Reseller contacts with
automatic access to the trouble tickets via web interfaces.

PSI Backbone status information must also be made available to IXC Reseller
contacts requesting same via the same interfaces.

7.4.3.      IXC ACCESS TO TROUBLE TICKETING SYSTEM

IXC must be provided access by PSI to any trouble tickets related to the
service provide to IXC, IXC Resellers and their end customers, as soon as the
technology is available to PSI. If additional programming is required to
deliver this functionality, it will be costed out and provided to IXC in
advance. The trouble ticketing system should provide designated IXC contacts
with automatic access to the trouble tickets via web interfaces.


*  Confidential material has been omitted and filed separately with the
   Securities and Exchange Commission


                    Attachments to Schedule 2.2
                       Page 18 of 34

<PAGE>
PSI Backbone status information must also be made available to IXC Reseller
contacts requesting same via the same interfaces.

PSI is to work with IXC to integrate trouble ticketing systems and processes as
much as reasonably possible.

7.5.        PROBLEM NOTIFICATION

7.5.1.      IXC CUSTOMER PROBLEM NOTIFICATION

PSI must inform the technical contact of IXC Switched LAN Internet Access
service customers of any outages affecting their service. The operations staff
must also keep Switched LAN Internet Access customers informed of any
widespread outages on connecting networks.

7.5.2.      IXC RESELLER PROBLEM NOTIFICATION

The PSI operations staff must inform the technical contact of IXC Resellers of
any outages affecting service to their end customers. The operations staff must
also keep IXC Resellers informed of any widespread outages on connecting
networks.

7.5.3.      IXC PROBLEM NOTIFICATION

The PSI operations staff must inform the IXC technical contacts of any outages
affecting service to IXC, IXC Resellers, or IXC end customers. The operations
staff must also keep IXC informed of any widespread outages on connecting
networks.

7.6.        SOFTWARE AND CONFIGURATION SUPPORT

PSI is responsible for coordinating software updates and configuration changes
on the customer premise router and CSU/DSU equipment of IXC customers as
required to provide Internet service. Notice of software changes is to be made
to the customer technical contacts, and every effort must be made to perform
maintenance during off-hours.

7.7.        ESCALATION PROCEDURES

Documented customer support processes are to be developed by PSI. Specific
process documentation is required for the following:

            o        customer support procedures
            o        trouble escalation procedures
            o        trouble ticketing, tracking, and resolution

PSI must provide information to the IXC customer describing customer support,
problem resolution, and trouble escalation procedures, customer contact
information, and trouble reporting methods.

8.           SECURITY PROCEDURES

The following services provide security procedures: RouteWaller (InterFrame),
SecureEnterprise (InterFrame and InterMAN), and PSI IntraNet.

Additionally, PSI's Net Abuse policy shall apply to all IXC customers.




                    Attachments to Schedule 2.2
                      Page 19 of 34

<PAGE>

MANAGED INTRANET WAN SERVICE SERVICE REQUIREMENTS VERSION 1.1

1.          OVERVIEW

PSI's Managed Intranet WAN services provide private IP networking with mediated
Internet access for a single organizations with multiple site. Private internal
IP traffic is logically isolated from the public Internet through integration
of Frame Relay PVCs and managed private routing. Exchange traffic between the
customer's private intranet and the public Internet is mediated through a
centrally specified security policy which is implemented globally at all
intranet sites. External traffic never intermingles with internal traffic. The
service is a fully managed turnkey solution that includes all necessary CPE
required to deliver the service.

The PSI Managed Intranet services include:

o PSI IntraNet

The PSI Managed Intranet service specification is included in Schedule 2.2.

2.          WHOLESALE SERVICE BRANDING

PSI is to deliver the Managed Intranet WAN service to IXC and IXC Customers on
a branded basis, such that the service is delivered to the end customer as an
IXC or IXC Reseller branded service. Service branding is to be present in the
following areas:

            o        Sales collateral
            o        Service manuals and other service-related material
            o        All PSI contact with the end customer, such as during
                     order verification, service provisioning, and customer
                     support
            o        Email addresses and web site domain names for customer
                     support, service status, service information
            o        Service usage reports

Where additional investment and resources are required, PSI will state
estimated costs in advance for which IXC or the IXC Reseller is responsible.

3.          DELIVERY PROCESSES

Documented delivery processes are to be developed by PSI. PSI will work to
integrate internal processes with IXC's service processes, specifically in the
areas of:

            o        Sales support
            o        Order processing
            o        Service provisioning
            o        Customer support
            o        Network operation procedures and escalation
            o        Trouble ticketing and tracking
            o        Billing

PSI must create and maintain delivery process documentation specific to the
items listed above.





                    Attachments to Schedule 2.2
                        Page 20 of 34

<PAGE>
4.          SERVICE IMPLEMENTATION

PSI's Managed Intranet WAN Service is to provide to IXC and IXC resellers:

            o        Full service provisioning, through IXC, of all
                     communications circuits and hardware, including ordering,
                     installation, and configuration
            o        Provisioning and maintenance of customer premise equipment
                     - CSU/DSUs and IP routers
            o        Internet service provisioning and configuration ( * where
                     appropriate, DNS, routing, etc) for the customer's
                     network
            o        Registration of customer's domain name
            o        Configuration and management of the Intranet WAN CPE
                     routers
            o        24 x 7 proactive network monitoring, fault isolation, and
                     management
            o        Single point of contact for trouble reporting and problem
                     resolution
            o        Security policy planning and management services for
                     Internet access control

PSI's installation technicians are responsible for remotely assisting the
customer's technical liaison in the physical installation of the customer
premise equipment (CPE).

Service implementation details are described below.

4.1.        SITE PLANNING AND PREPARATION COORDINATION

Site planning coordination is to be provided by PSI to the customer's
designated point of contact. This helps customers to prepare for installation
of the Intranet WAN service. Customers need to provide space and power for the
CPE equipment, an attachment to the customer's internal network, and at least
one computer with TCP/IP support.

4.2.         COMMUNICATIONS CIRCUIT ORDERING

PSI is responsible for ordering (from IXC, on behalf of the customer) and
maintaining the communications circuits necessary for delivery of service. IXC
will either provide the circuits itself or order them from another
telecommunications vendor at IXC's expense.

4.2.1       INSIDE WIRING

PSI will coordinate with the customer on inside wiring. The customer should
arrange for the circuit to terminate in proximity to the planned location of
the premises equipment. Any cost associated with extending the circuit to the
planned location of the premises equipment (inside wiring) is the
responsibility of customer.

4.3.        24 X 7 PROACTIVE NETWORK MONITORING, FAULT ISOLATION, AND
MANAGEMENT

PSI is to provide 24 x 7 monitoring of the Intranet WAN service. Any detected
faults are acted upon immediately, isolated to their cause, and proactively
managed through resolution.


*    Confidential material has been  omitted  and filed separately with the
     Securies and Exchange Commission.




                    Attachments to Schedule 2.2
                      Page 21 of 34

<PAGE>
4.4.        SINGLE POINT OF CONTACT

PSI is to provide the IXC customer with a single point of contact for trouble
reporting and resolution for any problems related to the Intranet WAN service.
PSI is responsible for interacting with all communications circuit and hardware
equipment vendors as needed to maintain the Intranet WAN.

4.5.        NETWORK USAGE STATISTICS REPORTING

PSI is responsible for producing Network Usage Statistics Reports as part of
the Managed Intranet WAN service. Reports are to include a traffic summary that
allows customers to track WAN line utilization and peak activity periods. The
usage report is to be produced on a regular basis (daily, weekly, and monthly)
and is to be provided to the customer via email and/or the Web. The usage
information is to be collected from the customer premises equipment using SNMP
tools, among other methods.

4.6.        CUSTOMER PREMISE EQUIPMENT

The customer premises equipment package consists of a TCP/IP router with
appropriate LAN and WAN interfaces, a CSU/DSU corresponding to the connection
type, and associated cables.

PSI provides all necessary CPE required for the Managed Intranet WAN service.

4.6.1.      CUSTOMER PREMISE EQUIPMENT STAGING AND CONFIGURATION

PSI is responsible for pre-configuring the CPE before delivery to the customer
sites and remotely configuring the CPE after it is connected to the network.
PSI remotely assists the customer's technical liaison in the installation of
the premises equipment at each Intranet WAN site. The customer's technical
liaison performs the physical installation of the premises equipment. On-site
CPE installation by an PSI field technician or agent is to be made available by
PSI to the IXC Customer on an optional basis.

4.6.2.      CPE ROUTER MANAGEMENT

As a part of the Managed Intranet WAN service, PSI is responsible for managing
the CPE routers at each site on the Intranet WAN on an ongoing basis.
Management is to include:

            o        Router software upgrades
            o        Router access control list changes as requested by IXC or
                     the IXC customer
            o        Router configuration changes as new sites are added to the
                     Intranet WAN
            o        24 x 7 monitoring of the Intranet WAN for inter-site
                     connectivity
            o        24 x 7 monitoring of the Intranet WAN routers for correct
                     operation
            o        24 x 7 monitoring of Intranet WAN line utilization
            o        Generation of usage statistics reports on a daily, weekly,
                     and monthly basis

4.7.        ACCEPTANCE TESTING

PSI is to conduct ping test to the customer's site to ensure that the customer
premise router can successfully communicate over the IXC Managed Intranet WAN
service and service billing by PSI to IXC may be initiated. Additional tests
will be performed thereafter to verify the proper operation of the on-site
equipment package, the local access facility, and the PSI infrastructure.




                    Attachments to Schedule 2.2
                       Page 22 of 34

<PAGE>
4.8.        ACCEPTANCE CRITERIA

PSI implementation of service for IXC Managed Intranet WAN service customers is
considered complete when the following criteria have been met:

4.8.1       Circuits and PVCs have been installed at each site and configured
to give the customer the amount of bandwidth contracted for between the
customer location and the PSI Point-of-Presence (POP).

4.8.2       The Managed Intranet WAN router and associated premises equipment
is installed at the customer site, and IP connectivity exists between the
customer networks at each site and the Internet (including routing outside PSI
networks). PSI must verify IP connectivity through a test which:

            (i) sends repeated pings through the Internet to the customer site
and verifies that the pings were received.

            (ii) in cases when the premises equipment configuration supports
it, PSI must verify IP routing through a traceroute test.

*

            (iv) Any necessary routing changes have been made in PSI's network
routers so that routes to the customers IP networks and addresses are announced
to the Internet.

            (v) For customers with their own domain, the domain is registered
with the InterNIC and any PSI-supplied primary and secondary DNS servers are
operational for it.

            (vi) Any initial customer requested packet-filtering option has
been installed in the customer premise Managed Intranet WAN router.

            (vii) The customer has been informed that the Internet service is
available from implementation of Internet application such as, Telnet, FTP,
E-Mail or WWW, and has acknowledged that they plan to configure these
applications within the installation phase or that they do not intend to at
this time. Billing will commence upon a successful ping test and not acceptance
of working Internet application.

            (viii) The customer has been informed of the operational status of
the customer's Intranet WAN connection and been provided with documentation of
(i) the Intranet WAN service configuration, and (ii) the acceptance test
results.

            (ix) IXC has been informed of the operational status of the
customer's Intranet WAN connection and been provided with documentation of (i)
the Intranet WAN service configuration, and (ii) the acceptance test results.

            (x) The IXC customer has been given an information package designed
for new Managed Intranet WAN customers.

5.          SERVICE OPTIONS

There are currently no service options available with the Managed Intranet WAN
service.


*     Confidential material has been omitted and  filed separately with the
      Securities and Exchange Commission.




                    Attachments to Schedule 2.2
                      Page 23 of 34

<PAGE>
6.          NETWORK OPERATIONS SUPPORT

PSI is responsible for network operations support for network services provided
to IXC Managed Intranet WAN service as described in this section.

6.1.        PSI INFRASTRUCTURE OPERATIONS SUPPORT

PSI must monitor the PSI network 24 hours a day, 365 days a year. PSI is to
provide proactive operations support and troubleshooting of all network and
service infrastructure components providing service to IXC customers, including
IXC-provided circuits (such as circuits from the PSI POP to the customer
premise).

PSI will use SNMP and other software tools to monitor the network. This
software must be supplemented with additional tools to monitor non- SNMP
equipment, domain name servers, NNTP news servers and feeds, and other network
services.

All network services (routing, DNS, email servers, NTP, security, etc.) must be
monitored for availability and performance. The monitoring software must report
the status of the network to a display which is monitored throughout the day.

Service outages are to be automatically detected. Troubleshooting procedures
and customer notification will occur within * of an outage.

IXC and PSI will work jointly on resolution procedures.

6.1.1.      NETWORK REPORTS.

PSI is to provide IXC with network status logs on a regular basis to provide
IXC with the ability to evaluate staff responsiveness and network availability.
All changes in the PSI network status must be logged.

PSI is to provide IXC with regular reports on the status of the PSI network.
Report information is to be defined by IXC, and will include but not be limited
to:



*

Please see example attached.

6.2.        CUSTOMER CONNECTIVITY SUPPORT

PSI must monitor IXC Intranet WAN customers' connectivity to ensure continuous
IP connectivity among the Intranet WAN sites. IXC customer's Intranet WAN
connectivity outages must be detected by PSI and acted upon by PSI within *  .

PSI must follow up on loss of connectivity using documented trouble resolution
procedures as jointly developed by IXC and PSI.

6.3.        COMMUNICATIONS LIK MAINTENANCE


*     Confidential material has been omitted and filed  separately with the
      Securities and Exchange Commission.





                    Attachments to Schedule 2.2
                      Page 24 of 34

<PAGE>
PSI is responsible for monitoring and maintaining the communications link
between the customer and PSI. This includes problem diagnosis and any necessary
vendor interaction for dispatch and repair. PSI's staff is to escalate
communications circuit problems using documented trouble resolution procedures
as jointly developed by IXC and PSI.

6.4.        CUSTOMER PREMISES EQUIPMENT  MAINTENANCE FOR INTERMAN

If the customer has contracted for customer premise Internet router and CSU/DSU
maintenance, PSI is responsible for maintaining the customer premise equipment.
PSI must diagnose failures, usually with the assistance of the technical
liaison designated by the customer at the site, and shall determine whether
equipment replacement is required.

6.4.1.      ON-SITE CPE REPAIR / REPLACEMENT FOR INTERMAN

PSI is responsible for performing the actual equipment replacement with
telephone assistance (as necessary).

Response time for performing customer premise equipment replacement must meet
the schedule described within the PSI customer maintenance contract.

7.          TECHNICAL SSERVICES AND CCUSTOMER SUPPORT

IXC is to provide first level customer support for all IXC Managed Intranet WAN
customers.

7.1.        STANDARD SERVICE CUSTOMER SUPPORT HELPLINE

PSI must staff an IXC Customer Support line with trained and qualified PSI
customer support representatives from 8am-8pm EST/EDT Monday through Friday.
Customer support staff must be trained in supporting Managed Intranet WAN
service customers. Additionally, an outage support hotline (Netwatch) shall be
staffed 24 hours per day, 7 days per week, 365 days per year for network access
emergency reporting to IXC and its customers.

7.1.1.      CUSTOMER SUPPORT HELPLINE RESPONSE TIME

Calls to the PSI-provided IXC customer support hotline must be answered within
seven rings., 8am-8pm EST/EDT Monday through Friday. For similar response times
off-hours, optional support may be available (at additional cost).

7.2.        CUSTOMER SUPPORT EMAIL MAILBOX

            See section 7.4

7.3.        FAULT ISOLATION AND PROBLEM RESOLUTION

PSI is to perform fault isolation for problems related to the PSI provided
service. Fault isolation may involve coordination among network operators and
technicians, staff at the affected site, telecommunications carriers, and other
vendors. Depending on the specific technologies used, the process may involve
testing equipment, reconfiguring routers, or diagnosing communications link
problems. PSI is responsible for diagnosing service problems and tracking
repair progress. PSI is to use documented trouble resolution procedures as
jointly developed and agreed upon by PSI and IXC.

7.4.        TROUBLE TICKETING SYSTEM





                    Attachments to Schedule 2.2
                         Page 25 of 34

<PAGE>
PSI must use a Trouble Ticketing System to track problems from initial report
through satisfactory resolution. As PSI works to resolve problems, the current
status must be maintained in the Trouble Ticketing System.

7.4.1.      IXC CUSTOMER ACCESS TO TROUBLE TICKETING SYSTEM

IXC customers will be provided access by PSI to any trouble tickets related to
their service, as soon as the technology is available to PSI. If additional
programming is required to deliver this functionality, it will be costed out
and provided to IXC in advance. The trouble ticketing system should provide
designated customer contacts with automatic access to the trouble tickets via
web interfaces.

PSI Backbone status information should also be made available to customer
contacts requesting same via the same interfaces.

7.4.2.      IXC RESELLER ACCESS TO TROUBLE TICKETING SYSTEM

IXC resellers will be provided access by PSI to any trouble tickets related to
the service, as soon as the technology is available to PSI. If additional
programming is required to deliver this functionality, it will be costed out
and provided to IXC in advance. The trouble ticketing system should provide
designated IXC Reseller contacts with automatic access to the trouble tickets
via web interfaces.

PSI Backbone status information should also be made available to IXC Reseller
contacts requesting same via the same interfaces.

7.4.3.      IXC ACCESS TO TROUBLE TICKETING SYSTEM

IXC will be provided access by PSI to any trouble tickets related to the
service provided to IXC, IXC Resellers and their end customers, as soon as the
technology is available to PSI. If additional programming is required to
deliver this functionality, it will be costed out and provided to IXC in
advance. The trouble ticketing system should provide designated IXC contacts
with automatic access to the trouble tickets via web interfaces

PSI Backbone status information should also be made available to IXC Reseller
contacts requesting same via the same interfaces

PSI is to work with IXC to integrate trouble ticketing systems and processes as
much as reasonably possible.

7.5.        PROBLEM NOTIFICATION.

                     7.5.1.   IXC CUSTOMER PROBLEM NOTIFICATION. PSI must
inform the technical contact of IXC Managed Intranet WAN service customers of
any outages affecting their service. The operations staff must also keep
Managed Intranet WAN customers informed of any widespread outages on connecting
networks

                     7.5.2.   IXC RESELLER PROBLEM NOTIFICATION. PSI must
inform the technical contact of IXC Resellers of any outages affecting service
to their end customers. The operations staff must also keep IXC Resellers
informed of any widespread outages on connecting networks

                     7.5.3.   IXC PROBLEM NOTIFICATION. PSI must inform the IXC
technical contacts of any outages affecting service to IXC, IXC Resellers, or
IXC end customers. The operations staff must also keep IXC informed of any
widespread outages on connecting networks





                    Attachments to Schedule 2.2
                        Page 26 of 34

<PAGE>
7.6.  Software and Configuration Support for InterMAN. PSI is responsible for
coordinating software updates and configuration changes on the customer premise
router and CSU/DSU equipment of IXC customers as required to provide Internet
service. Notice of software changes is to be made to the customer technical
contacts, and every effort must be made to perform maintenance during off-hours

7.7   Escalation Procedures. Documented customer support processes are to be
developed jointly by PSI and IXC. Specific process documentation is required
for the following:

            o        customer support procedures

            o        trouble escalation procedures

            o        trouble ticketing, tracking, and resolution

PSI must provide information to the IXC customer describing customer support,
problem resolution, and trouble escalation procedures, customer contact
information, and trouble reporting methods.

8.          SECURITY PROCEDURES

PSI's security procedures include a default Interim Security Policy for new
intranet sites, security policy planning before the sites are integrated into
an intranet, verification of identity of the customer technical contact before
requests for changes are accepted, and sign-off by the customer technical
contact of implementation plans before changes are implemented

Additionally, PSI's Net Abuse policy shall apply to all IXC customers.




                    Attachments to Schedule 2.2
                       Page 27 of 34

<PAGE>

INTERNET REMOTE ACCESS SERVICE SERVICE REQUIREMENTS VERSION 1.1

1.          OVERVIEW

The PSI Internet Remote Access service provides on-demand switched connectivity
to the Internet for corporate user groups of telecommuters and mobile workers
via analog modems (9.6 - 33.6 Kbps) or ISDN NT1s (64 - 128 Kbps), and
centralized account management by the customer technical administrator through
a web-based Account Management System. Connectivity is provided for client
access for single systems. Connections are established between the users and a
PSI Point-of-Presence (POP) using the Point-to-Point Protocol (PPP).

The PSI Internet Remote Access services include:

            o        InterRamp Remote Access for Business

The PSI Remote Access service specification is included in Schedule 2.3.

Additional service requirements to be decided.




                    Attachments to Schedule 2.2
                         Page 28 of 34

<PAGE>

MANAGED INTERNET SECURITY SERVICES SERVICE REQUIREMENTS VERSION 1.1


1.          OVERVIEW

PSI's Managed Internet Security services provide security policy planning and
implementation for Internet access control and remote user authentication
services. Security services are provided to the customer as a value-added
option to a PSI Dedicated Internet Access service, and include all necessary
CPE required to deliver the service.

The PSI Managed Internet Security services include:

            o        RouteWaller (for InterFrame)

            o        SecureEnterprise (for InterFrame and InterMAN)

The PSI Managed Internet Security service specifications are included in
Schedule 2.3.

Additional service requirements to be decided.




                    Attachments to Schedule 2.2
                      Page 29 of 34

<PAGE>

INTERNET FAX SERVICE SERVICE REQUIREMENTS VERSION 1.1


1.          OVERVIEW

PSI's Internet Fax service provides global hardcopy delivery of documents
through the Internet to any fax machine in the world. Traffic is routed from
the fax client on the customer user desktop to a server where the best price
can be attained for the final dial-out connection.

The PSI Internet Fax services include:

            o        PSInet InternetPaper

The PSI Internet Fax service specification is included in Schedule 2.3.

Additional service requirements to be decided.




                    Attachments to Schedule 2.2
                       Page 30 of 34

<PAGE>

WHOLESALE DIAL-UP INTERNET ACCESS SERVICE REQUIREMENTS VERSION 1.0



1.          OVERVIEW

PSI's Wholesale Dial-up Internet Access services provide, on a wholesale basis,
on-demand switched connectivity to the Internet via an analog modem (9.6 - 33.6
Kbps) or an ISDN NT1 (64 - 128 Kbps). The PSI Wholesale Dial-up Internet Access
services include:

            o        PSINet Consumer Wholesale

The PSInet Consumer Wholesale service descriptions are included in Schedule
2.3.

2.          WHOLESALE SERVICE BRANDING

PSI is to deliver the Dial-up Internet Access service on a branded basis, such
that the service is delivered to the end customer as an IXC / IXC reseller
branded service. Service branding is to be present in the following areas:

            o        Sales collateral
            o        End user software diskettes
            o        User manuals and other service-related material.
            o        All PSI contact with the end customer, such as during
                     order verification, service provisioning, and customer
                     support
            o        Email addresses and web site domain names for customer
                     support, service status, service information.
            o        Domain names used for end user account, as reflected in
                     user email addresses and user web page location
                     identifiers.
            o        Service usage reports

PSI will provide service branding pricing under separate cover.

3.          DELIVERY PROCESSES

Documented delivery processes are to be developed by PSI and are subject to
approval by IXC. PSI will work to integrate internal processes with IXC's
service processes, specifically in the areas of:

            o        order processing
            o        service provisioning
            o        customer support
            o        network operation procedures and escalation
            o        trouble ticketing and tracking
            o        billing

PSI must create and maintain delivery process documentation specific to the
items listed above.

PSI has created the processes above and have incorporated them into the
Consumer Wholesale Users Guide, previously supplied to IXC.

4.          SERVICE IMPLEMENTATION

PSI is to provide IXC with a dial-up Internet access product. RADIUS
authentication shall be performed by PSI. PSI provides modem ports, traffic
propagation, authentication and second level support. Customer support,
software fulfillment and billing may be outsourced.




                    Attachments to Schedule 2.2
                          Page 31 of 34

<PAGE>
Implementation details are described below.

4.1.        DIAL-UP POP INFRASTRUCTURE

PSI is responsible for installing and maintaining the network infrastructure
for providing analog and ISDN dial-up Internet access at multiple dial-up
Points-of-Presence (dial-up POPs) across the U.S. as well as 800 number
Internet access.

4.1.1.      PORT AVAILABILITY

PSI is responsible for maintaining an adequate number of modem and ISDN ports
for the dial-up service at each dial-up POP, based on the ratio of user
accounts to modem ports (user:modem ratio). User:Port ratios are to be
maintained at no more than approximately * at each PSI dial- up POP. PSI is to
monitor the user:port ratios of user accounts to available modem ports at each
dial-up POP. PSI will use best efforts to ensure the network is maintained at a
level which meet reasonable commercial standards and shall maintain its network
in good condition and repair. User:Port ratios are to be calculated for each
separate dial-up POP, with analog and ISDN ratios calculated separately.

PSI will provide IXC with real-time, 24hr/day access to its POPs for IXC's
analysis and debugging.

4.2.        RADIUS AUTHENTICATION

PSI is to install and maintain distributed RADIUS authentication servers to be
used for verifying user authentication. PSI's distributed RADIUS servers must
be configured to communicate with a central RADIUS server that contains the IXC
customer's authorized user database.

4.3.        OPTIONAL END USER SOFTWARE

PSI is to provide, for a fee, IXC or IXC Reseller branded, pre-configured
Internet access software on appropriate media (3.5" floppy or CD- ROM), and
appropriate operating system (Windows 3.1, Win 95, NT, MacOS).

4.3.1.      INTERNET CONNECTIVITY SOFTWARE SUITE

The end user dial-up access software is to include:

            o        An IP connectivity software suite of
            o        Dial-up communications
            o        TCP/IP stack
            o        PPP software
            o        Netscape or Internet Explorer web browser
            o        E-mail reader
            o        News reader
            o        Service Initiation Screens



*    Confidential material has been omitted and filed separately with  the
     Securities and Exchange Commission.




                    Attachments to Schedule 2.2
                       Page 32 of 34

<PAGE>
4.3.2.      SOFTWARE CUSTOMIZING AND BRANDING

The Internet access software media is to be available as private-label, branded
software. Branding is to include the following:

            o        Custom diskette packaging that reflects the IXC Customer
                     dial-up service brand
            o        Customized Service Initiation and Welcome screen
            o        Custom screen logo
            o        Custom initial default home page for the web browser
                     included with the software.
            o        Custom user manuals that reflects the IXC Customer dial-up
                     service brand.

4.3.3.      SOFTWARE FULFILLMENT

PSI is to arrange for the Internet access software to be delivered to the end
user upon receiving an account activation order for a new customer of the IXC
Reseller. The software shipment can be contracted by PSI to a fulfillment house
company that specializes in software diskette distribution. PSI is responsible
for the end user receiving the software no more than ten days following the
account activation order being received by PSI. PSI will provide a fee schedule
to IXC based on IXC sales projections given to the fulfillment house by PSI.

4.4.        OPTIONAL END USER HELP DESK

First tier end user help desk support is to be coordinated by PSI, or an agreed
upon subcontractor, for a fee. Help desk support is to include

            o        help regarding the installation and use of supported
                     desktop connectivity software, including web browser and
                     email
            o        trouble reporting regarding use of the wholesale dial-up
                     service
            o        general use of the dial-up service

Dial-up customer support is provided on a branded basis, with PSI customer
support representatives answering the phone in the name of the IXC Reseller.
Fees for this service are directly proportional with the amount of users the
IXC Reseller has using the network and are priced out separately for each
participating IXC Reseller. Call answering is to be customized in accordance
with the IXC Reseller's policies and procedures and may add additional cost to
each IXC Reseller.

4.5.        OPTIONAL EMAIL SERVICES

End user email services are to be offered by PSI, or its subcontractor, for an
added fee. Wholesale dial-up user mailboxes are to be hosted by PSI on a
managed, industry standard SMTP/POP3 e-mail server. Each user is to be provided
with their own email address and storage for up to 5 MB or 35 days of unread
mail, whichever is less. The mailserver is to be configured using a domain name
specific to the IXC Customer's branded dial-up service, which is the domain
name that is to appear in the end-users' email addresses.

PSI, or its subcontractor, is to host and manage the mail service with the same
robustness and operational care as is considered best practice within the
industry. PSI, or its subcontractor, is responsible for providing to IXC and
the IXC Reseller Web-based email administration tools for managing the email
service.





                    Attachments to Schedule 2.2
                         Page 33 of 34

<PAGE>
4.6         OPTIONAL USENET NEWS SERVICES

End user Usenet News services are offered by PSI to IXC Wholesale Dial-up
customers. An additional fee may apply.

4.7         ACCOUNT USAGE CALL RECORDS

PSI, or its subcontractor, is responsible for reporting detailed account call
record information to the IXC on a regular basis (daily, weekly, monthly).
Separate call record information must be provided to IXC for each IXC reseller
customer, as well as total aggregate call record information. Call records are
to be provided via electronic files as well as via a secure Web server
accessible to the IXC. PSI will provide a fee schedule based on these criteria.




                    Attachments to Schedule 2.2
                         Page 34 of 34

<PAGE>

SCHEDULE 2.3

DOCUMENTATION



1.          Service Descriptions - As per the Attachments to Schedule 2.2

2.          Standard Contract - PSI Standard Customer Agreement and all Addenda

3.          *

            Other Marketing Materials/Collateral



*     Confidential material  has been omitted and filed separately with the
      Securities and Exchange Commission.




                           Schedule 2.3
                                Page 1 of 1

<PAGE>

                           SCHEDULE 3.1

                           SALES SUPPORT


3.1   PSI will produce * for IXC.  A program outline shall be provided by
      August 1, 1997 and the initial drafts of the program shall be provided by
      PSI to IXC no later than August 15, 1997.  The program package will
      include * provided by PSI to IXC within 48 hours of the execution date.

3.2   PSI will * for IXC by no later than January 1, 1998.   *  shall be agreed
      upon by IXC and PSI.  IXC will pay * for PSI employees related to the * .
      PSI will pay all expenses associated with *.  IXC will bear the costs of
      *.

3.3    * by PSI sufficiently to meet the needs of IXC.  *.

3.4   PSI will establish * email list by August 15, 1997 to help *.  This is a
      general * will be monitored by experienced  *.

3.5   PSI will create or cause to be created * by no later than the end of
      3Q97.  * other appropriate information which will enhance and supplement
      * .

3.6   At additional cost where noted, PSI will do each of the following:

      (a)   PSI will provide additional * at prices to be agreed by IXC, with
            IXC responsible for reasonable *  of PSI personnel * .

      (b)   PSI will provide IXC * basis at no charge.

      (c)   To the extent permitted by applicable law, PSI will provide IXC
            with * basis at no charge.

      (d)   PSI will entertain * at IXC's request.





*     Confidential material has  been omitted and filed separately with the
      Securities and Exchange Commission.




                           Schedule 3.1
                            Page 1 of 1

<PAGE>

                          SCHEDULE 5.4.1

                 PROVISION GOVERNING IXC USE OF SERVICES

The following provisions shall apply to IXC's use of Services in IXC's capacity
as an end user of Services for its own account (provided that such provisions
shall be modified automatically to the extent PSI waives such provisions, or
imposes less restrictive provisions, on its customers under its standard terms
and conditions and normal business practices (including where exceptions are
routinely granted to customers), or for any other reseller or distributor of
services of the type comprising the Services):

(A)         IXC shall be solely responsible for the content of any
            transmissions over the Internet by IXC and any person or Third
            Party utilizing IXC's facilities with IXC's consent. IXC agrees
            that it and any such person or Third Party utilizing IXC's
            facilities shall not knowingly disrupt other network users, network
            services or network equipment. Disruptions include, but are not
            limited to, distribution of unsolicited advertising or chain
            letters, propagation of computer worms and viruses, and using the
            network to make unauthorized entry to any other machine accessible
            via the network.

(B)         Except as expressly set forth in or contemplated by the Joint
            Marketing and Services Agreement to which this Schedule is attached
            (the "Marketing Agreement"), PSI DISCLAIMS ALL EXPRESS AND IMPLIED
            WARRANTIES, INCLUDING WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
            A PARTICULAR PURPOSE. PSI shall not be liable for any damages that
            IXC may suffer arising out of use, or inability to use, the
            Services or products provided hereunder unless such damage is
            caused by a negligent, reckless or intentional act of PSI. PSI
            shall not be liable for unauthorized access by Third Parties to
            IXC's transmission facilities or premise equipment or for
            unauthorized access to or alteration, theft, loss or destruction of
            IXC's data files, programs, procedures or information through
            accident, fraudulent means or devices or any other method provided
            that the foregoing shall not relieve PSI from responsibility for
            any of the foregoing to the extent it results from PSI's actions
            (or inactions) while responsible for security and system
            administration within the IXC network. Except as expressly set
            forth in or contemplated by the Marketing Agreement, in any
            instance involving performance or nonperformance by PSI with
            respect to Services or products provided hereunder, (a) the price
            paid for Services which were not provided, or (b) in the case of
            products, the products shall be repaired or replaced by the
            manufacturer, subject to applicable warranty. Except as expressly
            set forth in or contemplated by the Marketing Agreement, in the
            case of refund for lost Services, credit will be issued only for
            periods of lost Service greater than twenty-four (24) hours.

(C)         IXC agrees to comply with U.S. law with regard to the transmission
            of technical data which is exported from the United States using
            the Services.

(D)         The following additional provisions shall apply to the following
            types of Services (as indicated): Dedicated Internet Access Service
            (PSINet InterFrame), Dedicated Internet Access Service (PSINet
            InterMAN), Switched LAN Internet Access Service, Managed Intranet
            WAN Service, Internet Remote Access Service, Managed Internet
            Security Services, PSINet InternetPaper Service and PSINet Consumer
            Wholesale Service:




                          Schedule 5.4.1
                               Page 1 of 23

<PAGE>
      DEDICATED INTERNET ACCESS SERVICE CUSTOMER CONTRACT PROVISIONS

                     PSINET INTERFRAME

                   PSINET NETWORK USAGE.

      A. COMPLIANCE WITH LAW AND POLICY. Customer has read and agrees to comply
      with PSINet's Net-Abuse Policy ("Policy") as currently set forth on
      PSINet's Web site (http://www.psi.net) and as the Policy may be modified
      by PSINet in its sole discretion from time to time. Any content,
      material, message or data made available or transmitted through the
      Service, wherever it is sent from, viewed, received, or retrieved, that
      is in violation of (i) any local, state, federal or international law,
      regulation or treaty; (ii) the Policy; or (iii) any community standard or
      accepted Internet policy is prohibited. Any such violation may be deemed
      a material breach of this Agreement and PSINet may, in its sole
      discretion, disable or terminate the Service with written notice to
      Customer, but without any cure period.

      B. CUSTOMER-ONLY TRAFFIC. The right to use the Service is strictly
      limited to Customer only and does not extend to any other person,
      corporation or entity except for wholly-owned affiliates of Customer and
      those members of Customer's staff and consultants in the course of
      performing work for Customer.

      C. THIRD-PARTY TRAFFIC. Customer may host world-wide web sites on behalf
      of third parties. In addition, Customer may feed USENET News to a third
      party, but may not send any posting from that third party, including, but
      not limited to, electronic mail, back to PSINet's wide-area network
      system (the "Network") or the Internet through the Service. Any other
      third party traffic, including packet access and electronic mail, whether
      sent or received through Customer's facilities by or on behalf of a third
      party through the Service, is expressly prohibited.

CUSTOMER NETWORK SECURITY. PSINet provides no user access security with respect
to any of Customer's facilities or facilities of others. Customer shall be
responsible for user/access security as well as access to its network or to the
Network. PSINet will assist in network security breach detection or
identification, but shall not be liable for any inability, failure or mistake
in doing so.

SERVICE ASSURANCE. If Customer notifies PSINet immediately upon its failure to
access the Network through Customer's standard means or the backup mechanisms
provided with the Service, and PSINet determines in its reasonable commercial
judgment that the Network is therefore unavailable to Customer ("Unavailable"),
one of the following will apply:

      1. If PSINet determines that the Network is Unavailable for one (1) or
      more consecutive hours during any calendar month, PSINet, upon Customer's
      request, will credit Customer's monthly invoice the pro-rated charges for
      one (1) day's Service fee; or

      2. If PSINet determines that the Network is Unavailable for an aggregate
      of four (4) or more hours during any calendar month, PSINet, upon
      Customer's request, will credit Customer's monthly invoice the pro-rated
      charges for one (1) week's Service fee.

These two options are not cumulative. For purposes of this section, scheduled
maintenance will not be considered to be Unavailability. PSINet shall not be
responsible for any toll charges incurred by Customer's use of any telephone
company ("Telco") or other telecommunications services as a result of this




                          Schedule 5.4.1
                             Page 2 of 23

<PAGE>
section. THE FOREGOING TWO OPTIONS STATE PSINET'S SOLE OBLIGATION, AND
CUSTOMER'S SOLE REMEDY, FOR NETWORK UNAVAILABILITY.

SPECIAL TERMS FOR THE "ON-SITE SERVICE" OPTION.

      "ON-SITE SERVICE" OPTION SPECIFICS.

      (1) EQUIPMENT ACCESS AND CONNECTION. The Equipment shall be installed and
      maintained by PSINet or its subcontractors as PSINet shall designate in
      writing. Customer shall provide 24 hour per day, 7 days per week access
      to the Equipment (with appropriate escort if required by Customer) by
      PSINet-designated individuals. If Customer cannot provide this access,
      any Service Assurance remedy provided above is suspended during such
      time. Customer shall not allow its personnel or others on its premises to
      tamper with the Equipment. PSINet will verbally authorize on an
      event-by-event basis individuals at Customer's location to open Equipment
      cabinets for appropriate routine and emergency reasons. Customer shall
      retain the right to disconnect the Equipment from its LAN at any time.
      PSINet reserves the right to shut down the Equipment at Customer's
      location in accordance with PSINet's emergency operating procedures with
      notification to Customer. Relocation of the Equipment may only be
      performed by PSINet or its subcontractors at Customer's expense. PSINet
      is not responsible for Service disruptions caused by Customer's Equipment
      relocation requirements.

      (2) SECURITY FILTERING SUB-OPTION. If initialed on Customer's Order Form,
      PSINet shall provide the Security Filtering Sub-Option along with the
      On-Site Service Option. PSINet shall provide packet filtering based on
      network number and protocol for non-Customer networks, and on an
      individual host basis for Customer host computers.

            (a) Customer will delegate two security contacts, a primary and a
            secondary. Contact names, phone numbers, fax numbers, and
            electronic mail addresses must be provided to PSINet on the Order
            Form. PSINet will take direction ONLY from these contacts.

            (b) Customer security contacts must participate in an initial phone
            consultation with PSINet's Security Coordinator.

            (c) Customer requests must be made by electronic mail or fax to the
            designated PSINet address to facilitate an audit trail.

            (d) PSINet Network Operations can be instructed by other Customer
            contacts to disable non-PSINet access (for instance, MAE-East and
            CIX access).

LIMITED WARRANTIES.

      A. SERVICE. PSINET WARRANTS THAT THE SERVICE WILL OPERATE SUBSTANTIALLY
      IN CONFORMANCE WITH THE SPECIFICATIONS. PSINET MAKES NO OTHER WARRANTIES
      OF ANY KIND, WHETHER EXPRESSED, IMPLIED OR STATUTORY, INCLUDING, BUT NOT
      LIMITED TO, ANY IMPLIED WARRANTY OF MERCHANTABILITY, FITNESS OF THE
      SERVICE FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT OF ANY THIRD PARTY
      RIGHTS. CUSTOMER IS RESPONSIBLE FOR ASSESSING ITS OWN COMPUTER AND
      TRANSMISSION NETWORK NEEDS, AND THE RESULTS TO BE OBTAINED THEREFROM. USE
      OF ANY INFORMATION OBTAINED THROUGH THE SERVICE IS AT CUSTOMER'S RISK.
      PSINET SPECIFICALLY DENIES ANY RESPONSIBILITY FOR THE ACCURACY OR QUALITY
      OF INFORMATION OBTAINED THROUGH THE SERVICE.

      B. EQUIPMENT. PSINET REPRESENTS AND WARRANTS THAT DURING THE TERM OF THIS
      AGREEMENT IT WILL MAKE REASONABLE EFFORTS TO ENSURE THE EQUIPMENT
      OPERATES




                          Schedule 5.4.1
                             Page 3 of 23

<PAGE>
      SUBSTANTIALLY IN CONFORMANCE WITH THE SPECIFICATIONS. ANY UNAUTHORIZED
      CHANGES TO OR INAPPROPRIATE USAGE OF THE EQUIPMENT, HOWEVER, WILL VOID
      THE FOREGOING WARRANTY. PSINET DOES NOT WARRANT THAT THE EQUIPMENT WILL
      BE ENTIRELY FREE FROM DEFECTS OR THAT ITS OPERATION WILL BE ERROR FREE.
      FURTHERMORE, CUSTOMER ACKNOWLEDGES THAT PSINET HAS MADE NO OTHER
      REPRESENTATION OR WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, WITH RESPECT
      TO THE CONDITION OR PERFORMANCE OF THE EQUIPMENT, OR ITS MERCHANTABILITY
      OR FITNESS FOR A PARTICULAR PURPOSE. C. GENERAL. EACH PARTY ACKNOWLEDGES
      THAT IT HAS READ AND UNDERSTANDS THIS AGREEMENT AND AGREES TO BE BOUND BY
      ITS TERMS. EACH PARTY FURTHER WARRANTS THAT IT HAS FULL CORPORATE POWER
      AND AUTHORITY TO ENTER INTO AND DELIVER THIS AGREEMENT AND TO PERFORM ITS
      OBLIGATIONS HEREUNDER, AND THAT THE PERSON WHOSE SIGNATURE APPEARS BELOW
      IS DULY AUTHORIZED TO ENTER INTO THIS AGREEMENT ON BEHALF OF THAT PARTY.

LIMITATION OF LIABILITY. EXCEPT FOR CUSTOMER'S PAYMENT OBLIGATIONS HEREUNDER,
NEITHER PARTY SHALL BE LIABLE FOR DIRECT DAMAGES GREATER THAN THE SUM TOTAL OF
PAYMENTS MADE BY CUSTOMER TO PSINET DURING THE SIX (6) MONTHS IMMEDIATELY
PRECEDING THE EVENT FOR WHICH DAMAGES ARE CLAIMED. EXCEPT FOR THE FOREGOING,
PSINET SHALL HAVE NO LIABILITY TO CUSTOMER WITH RESPECT TO (I) ANY CLAIM, LOSS
OR DAMAGE OF ANY KIND OR NATURE WHATSOEVER INCLUDING THE ACTIVE OR PASSIVE
NEGLIGENCE OR STRICT LIABILITY OF PSINET FOR CLAIMS ARISING OUT OF OR IN
CONNECTION WITH THE SERVICE OR THE EQUIPMENT, WHETHER OR NOT KNOWN OR DISCLOSED
TO PSINET; (II) ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, PUNITIVE OR
CONSEQUENTIAL LOSSES OR DAMAGES RESULTING FROM THE DELIVERY, INSTALLATION,
MAINTENANCE, OPERATION OR USE OF THE SERVICE OR THE EQUIPMENT; (III) ANY ACT OR
OMISSION OF ANY OTHER ENTITY FURNISHING EQUIPMENT, PRODUCTS OR SERVICES TO
CUSTOMER; (IV) ANY PERSONAL OR PROPERTY DAMAGES DUE TO THE LOSS OF STORED,
TRANSMITTED OR RECORDED DATA RESULTING FROM THE SERVICE OR THE EQUIPMENT, EVEN
IF PSINET HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH DAMAGES; AND (V) ANY LOSS
OR DAMAGES DUE TO THE FAULT OR NEGLIGENCE OF CUSTOMER OR ITS EMPLOYEES, AGENTS
OR REPRESENTATIVES.

IN NO EVENT SHALL EITHER PARTY BE LIABLE FOR ANY INDIRECT, INCIDENTAL,
EXEMPLARY, PUNITIVE OR OTHER CONSEQUENTIAL DAMAGES WHETHER OR NOT FORESEEABLE,
INCLUDING, BUT NOT LIMITED TO, DAMAGES FOR THE LOSS OF DATA, GOODWILL OR
PROFITS, ARISING OUT OF OR IN RELATION TO THIS AGREEMENT EVEN IF ADVISED
BEFOREHAND OF THE POSSIBILITY OF SUCH LIABILITY. THE PARTIES AGREE TO WORK IN
GOOD FAITH TO IMPLEMENT THE PURPOSES OF THIS AGREEMENT, BUT RECOGNIZE THAT THE
SERVICE COULD NOT BE MADE AVAILABLE UNDER THESE TERMS OR OTHER SIMILAR TERMS
WITHOUT A SUBSTANTIAL INCREASE IN COST IF PSINET WERE TO ASSUME A GREATER
DEGREE OF LIABILITY TO CUSTOMER.





                          Schedule 5.4.1
                             Page 4 of 23

<PAGE>
              DEDICATED INTERNET ACCESS SERVICE
                  CUSTOMER CONTRACT PROVISIONS


                                PSINET INTERMAN


PSINET NETWORK USAGE.

      A. COMPLIANCE WITH LAW AND POLICY. Customer has read and agrees to comply
      with PSINet's Net-Abuse Policy ("Policy") as currently set forth on
      PSINet's Web site (http://www.psi.net) and as the Policy may be modified
      by PSINet in its sole discretion from time to time. Any content,
      material, message or data made available or transmitted through the
      Service, wherever it is sent from, viewed, received, or retrieved, that
      is in violation of (i) any local, state, federal or international law,
      regulation or treaty; (ii) the Policy; or (iii) any community standard or
      accepted Internet policy is prohibited. Any such violation may be deemed
      a material breach of this Agreement and PSINet may, in its sole
      discretion, disable or terminate the Service with written notice to
      Customer, but without any cure period.

      B. CUSTOMER-ONLY TRAFFIC. The right to use the Service is strictly
      limited to Customer only and does not extend to any other person,
      corporation or entity except for wholly-owned affiliates of Customer and
      those members of Customer's staff and consultants in the course of
      performing work for Customer.

      C. THIRD-PARTY TRAFFIC. Customer may host world-wide web sites on behalf
      of third parties. In addition, Customer may feed USENET News to a third
      party, but may not send any posting from that third party, including, but
      not limited to, electronic mail, back to PSINet's wide-area network
      system (the "Network") or the Internet through the Service. Any other
      third party traffic, including packet access and electronic mail, whether
      sent or received through Customer's facilities by or on behalf of a third
      party through the Service, is expressly prohibited.

CUSTOMER NETWORK SECURITY. PSINet provides no user access security with respect
to any of Customer's facilities or facilities of others. Customer shall be
responsible for user/access security as well as access to its network or to the
Network. PSINet will assist in network security breach detection or
identification, but shall not be liable for any inability, failure or mistake
in doing so.

      PSINET-PROVIDED EQUIPMENT.

      (1) EQUIPMENT SPACE. Customer shall provide and maintain suitable
      Equipment Space meeting or exceeding the requirements set forth in the
      Specifications.

      (2) EQUIPMENT. The Equipment Space will house Equipment owned by PSINet
      required for the Service. PSINet shall retain all right, title, and
      interest in the Equipment at all times. PSINet will provide Equipment in
      order to facilitate the connection between Customer's network and the
      Telco circuit leading to the Network. The particular make and model of
      Equipment shall be selected for Customer by PSINet in its sole
      discretion. If PSINet determines in its sole reasonable judgment that the
      Equipment is defective, PSINet shall replace the defective Equipment at
      no cost to Customer. THE FOREGOING STATES PSINET'S SOLE OBLIGATION, AND
      CUSTOMER'S SOLE REMEDY, FOR ANY DEFECTIVE EQUIPMENT.





                          Schedule 5.4.1
                           Page 5 of 23

<PAGE>
      (3) EQUIPMENT ACCESS AND CONNECTION. The Equipment shall be installed and
      maintained by PSINet, or its subcontractors as PSINet shall designate in
      writing. Customer shall provide 24 hour per day, 7 days per week access
      to the Equipment (with appropriate escort if required by Customer) by
      PSINet-designated individuals. If Customer cannot provide this access,
      any Service Assurance remedy provided below is suspended during such
      time. Customer shall not allow its personnel or others on its premises to
      open the Equipment cabinets. PSINet will verbally authorize on an
      event-by-event basis individuals at Customer's location to open Equipment
      cabinets for appropriate routine and emergency reasons. Customer shall
      retain the right to disconnect the Equipment from its LAN at any time.
      PSINet reserves the right to shut down the Equipment at Customer's
      location in accordance with PSINet's emergency operating procedures with
      notification to Customer.

      (4) EQUIPMENT RELOCATION. Relocation of the Equipment may only be
      performed by PSINet or its subcontractors at Customer's expense. PSINet
      is not responsible for Service disruptions caused by Customer's Equipment
      relocation requirements.

      (5) EQUIPMENT RETURN. Upon termination of the Service for any reason,
      Customer agrees immediately to allow the return of the Equipment to
      PSINet. PSINet retains all rights to recover possession of the Equipment
      from Customer.

SECURITY FILTERING OPTION. If initialed on Customer's Order Form, PSINet shall
provide the Security Filtering Option. PSINet shall provide packet filtering
based on network number and protocol for non-Customer networks, and on an
individual host basis for Customer host computers.

      (1) Customer will delegate two security contacts, a primary and a
      secondary. Contact names, phone numbers, fax numbers, and electronic mail
      addresses must be provided to PSINet on the Order Form. PSINet will take
      direction ONLY from these contacts.

      (2) Customer security contact points must participate in an initial phone
      consultation with PSINet's Security Coordinator.

      (3) Customer requests must be made by electronic mail or fax to the
      designated PSINet address to facilitate an audit trail. (4) PSINet
      Network Operations can be instructed by other Customer contacts to
      disable non-PSINet access (for instance, MAE-East and CIX access).

SERVICE ASSURANCE. If Customer notifies PSINet immediately upon its failure to
access the Network through Customer's standard means or the backup mechanisms
provided with the Service, and PSINet determines in its reasonable commercial
judgment that the Network is therefore unavailable to Customer ("Unavailable"),
one of the following will apply:

      1. If PSINet determines that the Network is Unavailable for one (1) or
      more consecutive hours during any calendar month, PSINet, upon Customer's
      request, will credit Customer's monthly invoice the pro-rated charges for
      one (1) day's Service fee; or

      2. If PSINet determines that the Network is Unavailable for an aggregate
      of four (4) or more hours during any calendar month, PSINet, upon
      Customer's request, will credit Customer's monthly invoice the pro-rated
      charges for one (1) week's Service fee.

These two options are not cumulative. For purposes of this section, scheduled
maintenance will not be considered to be Unavailability. PSINet shall not be




                           Schedule 5.4.1
                             Page 6 of 23

<PAGE>
responsible for any toll charges incurred by Customer's use of any telephone
company ("Telco") or other telecommunications services as a result of this
section. THE FOREGOING TWO OPTIONS STATE PSINET'S SOLE OBLIGATION, AND
CUSTOMER'S SOLE REMEDY, FOR NETWORK UNAVAILABILITY.

LIMITED WARRANTIES.

      A. SERVICE. PSINET WARRANTS THAT THE SERVICE WILL OPERATE SUBSTANTIALLY
      IN CONFORMANCE WITH THE SPECIFICATIONS. PSINET MAKES NO OTHER WARRANTIES
      OF ANY KIND, WHETHER EXPRESSED, IMPLIED OR STATUTORY, INCLUDING, BUT NOT
      LIMITED TO, ANY IMPLIED WARRANTY OF MERCHANTABILITY, FITNESS OF THE
      SERVICE FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT OF ANY THIRD PARTY
      RIGHTS. CUSTOMER IS RESPONSIBLE FOR ASSESSING ITS OWN COMPUTER AND
      TRANSMISSION NETWORK NEEDS, AND THE RESULTS TO BE OBTAINED THEREFROM. USE
      OF ANY INFORMATION OBTAINED THROUGH THE SERVICE IS AT CUSTOMER'S RISK.
      PSINET SPECIFICALLY DENIES ANY RESPONSIBILITY FOR THE ACCURACY OR QUALITY
      OF INFORMATION OBTAINED THROUGH THE SERVICE.

      B. EQUIPMENT. PSINET REPRESENTS AND WARRANTS THAT DURING THE TERM OF THIS
      AGREEMENT IT WILL MAKE REASONABLE EFFORTS TO ENSURE THE EQUIPMENT
      OPERATES SUBSTANTIALLY IN CONFORMANCE WITH THE SPECIFICATIONS. ANY
      UNAUTHORIZED CHANGES TO OR INAPPROPRIATE USAGE OF THE EQUIPMENT, HOWEVER,
      WILL VOID THE FOREGOING WARRANTY. PSINET DOES NOT WARRANT THAT THE
      EQUIPMENT WILL BE ENTIRELY FREE FROM DEFECTS OR THAT ITS OPERATION WILL
      BE ERROR FREE. FURTHERMORE, CUSTOMER ACKNOWLEDGES THAT PSINET HAS MADE NO
      OTHER REPRESENTATION OR WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, WITH
      RESPECT TO THE CONDITION OR PERFORMANCE OF THE EQUIPMENT, OR ITS
      MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE.

      C. GENERAL. EACH PARTY ACKNOWLEDGES THAT IT HAS READ AND UNDERSTANDS THIS
      AGREEMENT AND AGREES TO BE BOUND BY ITS TERMS. EACH PARTY FURTHER
      WARRANTS THAT IT HAS FULL CORPORATE POWER AND AUTHORITY TO ENTER INTO AND
      DELIVER THIS AGREEMENT AND TO PERFORM ITS OBLIGATIONS HEREUNDER, AND THAT
      THE PERSON WHOSE SIGNATURE APPEARS BELOW IS DULY AUTHORIZED TO ENTER INTO
      THIS AGREEMENT ON BEHALF OF THAT PARTY.

LIMITATION OF LIABILITY. EXCEPT FOR CUSTOMER'S PAYMENT OBLIGATIONS HEREUNDER,
NEITHER PARTY SHALL BE LIABLE FOR DIRECT DAMAGES GREATER THAN THE SUM TOTAL OF
PAYMENTS MADE BY CUSTOMER TO PSINET DURING THE SIX (6) MONTHS IMMEDIATELY
PRECEDING THE EVENT FOR WHICH DAMAGES ARE CLAIMED. EXCEPT FOR THE FOREGOING,
PSINET SHALL HAVE NO LIABILITY TO CUSTOMER WITH RESPECT TO (I) ANY CLAIM, LOSS
OR DAMAGE OF ANY KIND OR NATURE WHATSOEVER INCLUDING THE ACTIVE OR PASSIVE
NEGLIGENCE OR STRICT LIABILITY OF PSINET FOR CLAIMS ARISING OUT OF OR IN
CONNECTION WITH THE SERVICE OR THE EQUIPMENT, WHETHER OR NOT KNOWN OR DISCLOSED
TO PSINET; II) ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, PUNITIVE OR
CONSEQUENTIAL LOSSES OR DAMAGES RESULTING FROM THE DELIVERY, INSTALLATION,
MAINTENANCE, OPERATION OR USE OF THE SERVICE OR THE EQUIPMENT; (III) ANY ACT OR
OMISSION OF ANY OTHER ENTITY FURNISHING EQUIPMENT, PRODUCTS OR SERVICES TO
CUSTOMER; (IV) ANY PERSONAL OR PROPERTY DAMAGES DUE TO THE LOSS OF STORED,
TRANSMITTED OR RECORDED DATA RESULTING FROM THE SERVICE OR THE EQUIPMENT, EVEN
IF PSINET HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH DAMAGES; AND (V) ANY LOSS
OR DAMAGES DUE TO THE FAULT OR NEGLIGENCE OF CUSTOMER OR ITS EMPLOYEES, AGENTS
OR REPRESENTATIVES.

IN NO EVENT SHALL EITHER PARTY BE LIABLE FOR ANY INDIRECT, INCIDENTAL,
EXEMPLARY, PUNITIVE OR OTHER CONSEQUENTIAL DAMAGES WHETHER OR NOT FORESEEABLE,
INCLUDING, BUT NOT LIMITED TO, DAMAGES FOR THE LOSS OF DATA, GOODWILL OR
PROFITS, ARISING OUT OF OR IN RELATION TO THIS AGREEMENT EVEN IF ADVISED
BEFOREHAND OF THE POSSIBILITY OF SUCH LIABILITY. THE PARTIES AGREE TO WORK IN
GOOD FAITH TO IMPLEMENT THE PURPOSES OF THIS AGREEMENT, BUT RECOGNIZE THAT THE
SERVICE COULD NOT BE MADE AVAILABLE UNDER THESE TERMS OR OTHER SIMILAR TERMS
WITHOUT A




                          Schedule 5.4.1
                           Page 7 of 23

<PAGE>
SUBSTANTIAL INCREASE IN COST IF PSINET WERE TO ASSUME A GREATER DEGREE OF
LIABILITY TO CUSTOMER.





                          Schedule 5.4.1
                            Page 8 of 23

<PAGE>
                SWITCHED LAN INTERNET ACCESS SERVICE
                  CUSTOMER CONTRACT PROVISIONS


PSINET NETWORK USAGE.

      A. COMPLIANCE WITH LAW AND POLICY. Customer has read and agrees to comply
      with PSINet's Net-Abuse Policy ("Policy") as currently set forth on
      PSINet's Web site (http://www.psi.net) and as the Policy may be modified
      by PSINet in its sole discretion from time to time. Any content,
      material, message or data made available or transmitted through the
      Service, wherever it is sent from, viewed, received, or retrieved, that
      is in violation of (i) any local, state, federal or international law,
      regulation or treaty; (ii) the Policy; or (iii) any community standard or
      accepted Internet policy is prohibited. Any such violation may be deemed
      a material breach of this Agreement and PSINet may, in its sole
      discretion, disable or terminate the Service with written notice to
      Customer, but without any cure period.

      B. CUSTOMER-ONLY TRAFFIC. The right to use the Service is strictly
      limited to Customer only and does not extend to any other person,
      corporation or entity except for wholly-owned affiliates of Customer and
      those members of Customer's staff and consultants in the course of
      performing work for Customer.

      C. THIRD-PARTY TRAFFIC. Customer may host world-wide web sites on behalf
      of third parties. In addition, Customer may feed USENET News to a third
      party, but may not send any posting from that third party, including, but
      not limited to, electronic mail, back to PSINet's wide-area network
      system (the "Network") or the Internet through the Service. Any other
      third party traffic, including packet access and electronic mail, whether
      sent or received through Customer's facilities by or on behalf of a third
      party through the Service, is expressly prohibited.

SERVICE USAGE. No more than one connection can be used at any time with a
Service as paid for by Customer and assigned by PSINet. If two individuals or
groups need to simultaneously access PSINet through separate phone lines, then
they would have to acquire two Services, and so on. Service use is defined as a
connection with a PSINet modem or access device using the public switched
telephone system (E.G. POTS lines or ISDN circuits). This single phone line
connection does allow for multiple individual user sessions.

CUSTOMER NETWORK SECURITY. PSINet provides no user access security with respect
to any of Customer's facilities or facilities of others. Customer shall be
responsible for user/access security as well as access to its network or to the
Network. PSINet will assist in network security breach detection or
identification, but shall not be liable for any inability, failure or mistake
in doing so.

SERVICE ASSURANCE. If Customer notifies PSINet immediately upon its failure to
access the Network through Customer's standard means, including multiple
alternative dialup POPs, provided with the Service, and PSINet determines in
its reasonable commercial judgment that the Network is therefore unavailable to
Customer ("Unavailable"), one of the following will apply:

      1. If PSINet determines that the Network is Unavailable for one (1) or
      more consecutive hours during any calendar month, PSINet, upon Customer's
      request, will credit Customer's monthly invoice the pro-rated charges for
      one (1) day's Service fee; or





                          Schedule 5.4.1
                           Page 9 of 23

<PAGE>
      2. If PSINet determines that the Network is Unavailable for an aggregate
      of four (4) or more hours during any calendar month, PSINet, upon
      Customer's request, will credit Customer's monthly invoice the pro-rated
      charges for one (1) week's Service fee.

These two options are not cumulative. For purposes of this section, scheduled
maintenance will not be considered to be Unavailability. PSINet shall not be
responsible for any toll charges incurred by Customer's use of any telephone
company ("Telco") or other telecommunications services as a result of this
section. THE FOREGOING TWO OPTIONS STATE PSINET'S SOLE OBLIGATION, AND
CUSTOMER'S SOLE REMEDY, FOR NETWORK UNAVAILABILITY.

LIMITED WARRANTIES.

      A. SERVICE. PSINET WARRANTS THAT THE SERVICE WILL OPERATE SUBSTANTIALLY
      IN CONFORMANCE WITH THIS AGREEMENT. PSINET MAKES NO OTHER WARRANTIES OF
      ANY KIND, WHETHER EXPRESSED, IMPLIED OR STATUTORY, INCLUDING, BUT NOT
      LIMITED TO, ANY IMPLIED WARRANTY OF MERCHANTABILITY, FITNESS OF THE
      SERVICE FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT OF ANY THIRD PARTY
      RIGHTS. CUSTOMER IS RESPONSIBLE FOR ASSESSING ITS OWN COMPUTER AND
      TRANSMISSION NETWORK NEEDS, AND THE RESULTS TO BE OBTAINED THEREFROM. USE
      OF ANY INFORMATION OBTAINED THROUGH THE SERVICE IS AT CUSTOMER'S RISK.
      PSINET SPECIFICALLY DENIES ANY RESPONSIBILITY FOR THE ACCURACY OR QUALITY
      OF INFORMATION OBTAINED THROUGH THE SERVICE.

      B. EQUIPMENT. PSINET REPRESENTS AND WARRANTS THAT DURING THE TERM OF THIS
      AGREEMENT IT WILL MAKE REASONABLE EFFORTS TO ENSURE THE EQUIPMENT
      OPERATES SUBSTANTIALLY IN CONFORMANCE WITH THIS AGREEMENT. ANY
      UNAUTHORIZED CHANGES TO OR INAPPROPRIATE USAGE OF THE EQUIPMENT, HOWEVER,
      WILL VOID THE FOREGOING WARRANTY. PSINET DOES NOT WARRANT THAT THE
      EQUIPMENT WILL BE ENTIRELY FREE FROM DEFECTS OR THAT ITS OPERATION WILL
      BE ERROR FREE. FURTHERMORE, CUSTOMER ACKNOWLEDGES THAT PSINET HAS MADE NO
      OTHER REPRESENTATION OR WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, WITH
      RESPECT TO THE CONDITION OR PERFORMANCE OF THE EQUIPMENT, OR ITS
      MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE.

      C. GENERAL. EACH PARTY ACKNOWLEDGES THAT IT HAS READ AND UNDERSTANDS THIS
      AGREEMENT AND AGREES TO BE BOUND BY ITS TERMS. EACH PARTY FURTHER
      WARRANTS THAT IT HAS FULL CORPORATE POWER AND AUTHORITY TO ENTER INTO AND
      DELIVER THIS AGREEMENT AND TO PERFORM ITS OBLIGATIONS HEREUNDER, AND THAT
      THE PERSON WHOSE SIGNATURE APPEARS BELOW IS DULY AUTHORIZED TO ENTER INTO
      THIS AGREEMENT ON BEHALF OF THAT PARTY.

LIMITATION OF LIABILITY. EXCEPT FOR CUSTOMER'S PAYMENT OBLIGATIONS HEREUNDER,
NEITHER PARTY SHALL BE LIABLE FOR DIRECT DAMAGES GREATER THAN THE SUM TOTAL OF
PAYMENTS MADE BY CUSTOMER TO PSINET DURING THE SIX (6) MONTHS IMMEDIATELY
PRECEDING THE EVENT FOR WHICH DAMAGES ARE CLAIMED. EXCEPT FOR THE FOREGOING,
PSINET SHALL HAVE NO LIABILITY TO CUSTOMER WITH RESPECT TO (I) ANY CLAIM, LOSS
OR DAMAGE OF ANY KIND OR NATURE WHATSOEVER INCLUDING THE ACTIVE OR PASSIVE
NEGLIGENCE OR STRICT LIABILITY OF PSINET FOR CLAIMS ARISING OUT OF OR IN
CONNECTION WITH THE SERVICE OR THE EQUIPMENT, WHETHER OR NOT KNOWN OR DISCLOSED
TO PSINET; (II) ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, PUNITIVE OR
CONSEQUENTIAL LOSSES OR DAMAGES RESULTING FROM THE DELIVERY, INSTALLATION,
MAINTENANCE, OPERATION OR USE OF THE SERVICE OR THE EQUIPMENT; (III) ANY ACT OR
OMISSION OF ANY OTHER ENTITY FURNISHING EQUIPMENT, PRODUCTS OR SERVICES TO
CUSTOMER; (IV) ANY PERSONAL OR PROPERTY DAMAGES DUE TO THE LOSS OF STORED,
TRANSMITTED OR RECORDED DATA RESULTING FROM THE SERVICE OR THE EQUIPMENT, EVEN
IF PSINET HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH DAMAGES; AND (V) ANY LOSS
OR DAMAGES DUE TO THE FAULT OR NEGLIGENCE OF CUSTOMER OR ITS EMPLOYEES, AGENTS
OR REPRESENTATIVES.





                          Schedule 5.4.1
                           Page 10 of 23

<PAGE>
IN NO EVENT SHALL EITHER PARTY BE LIABLE FOR ANY INDIRECT, INCIDENTAL,
EXEMPLARY, PUNITIVE OR OTHER CONSEQUENTIAL DAMAGES WHETHER OR NOT FORESEEABLE,
INCLUDING, BUT NOT LIMITED TO, DAMAGES FOR THE LOSS OF DATA, GOODWILL OR
PROFITS, ARISING OUT OF OR IN RELATION TO THIS AGREEMENT EVEN IF ADVISED
BEFOREHAND OF THE POSSIBILITY OF SUCH LIABILITY. THE PARTIES AGREE TO WORK IN
GOOD FAITH TO IMPLEMENT THE PURPOSES OF THIS AGREEMENT, BUT RECOGNIZE THAT THE
SERVICE COULD NOT BE MADE AVAILABLE UNDER THESE TERMS OR OTHER SIMILAR TERMS
WITHOUT A SUBSTANTIAL INCREASE IN COST IF PSINET WERE TO ASSUME A GREATER
DEGREE OF LIABILITY TO CUSTOMER.









                          Schedule 5.4.1
                           Page 11 of 23

<PAGE>
                         MANAGED INTRANET WAN SERVICE
                         CUSTOMER CONTRACT PROVISIONS


PSINET NETWORK USAGE.

      A. COMPLIANCE WITH LAW AND POLICY. Customer has read and agrees to comply
      with PSINet's Net-Abuse Policy ("Policy") as currently set forth on
      PSINet's Web site (http://www.psi.net) and as the Policy may be modified
      by PSINet in its sole discretion from time to time. Any content,
      material, message or data made available or transmitted through the
      Service, wherever it is sent from, viewed, received, or retrieved, that
      is in violation of (i) any local, state, federal or international law,
      regulation or treaty; (ii) the Policy; or (iii) any community standard or
      accepted Internet policy is prohibited. Any such violation may be deemed
      a material breach of this Agreement and PSINet may, in its sole
      discretion, disable or terminate the Service with written notice to
      Customer, but without any cure period.

      B. CUSTOMER-ONLY TRAFFIC. The right to use the Service is strictly
      limited to Customer only and does not extend to any other person,
      corporation or entity except for wholly-owned affiliates of Customer and
      those members of Customer's staff and consultants in the course of
      performing work for Customer.

      C. THIRD-PARTY TRAFFIC. Customer may host world-wide web sites on behalf
      of third parties. In addition, Customer may feed USENET News to a third
      party, but may not send any posting from that third party, including, but
      not limited to, electronic mail, back to PSINet's wide-area network
      system (the "Network") or the Internet through the Service. Any other
      third party traffic, including packet access and electronic mail, whether
      sent or received through Customer's facilities by or on behalf of a third
      party through the Service, is expressly prohibited.

CUSTOMER EQUIPMENT AND NETWORK. PSINet provides no user access security with
respect to any of Customer's facilities or facilities of others. PSINet will
assist in enforcing a customer-specified access policy as provided in the
Specifications subject to the limits of the implementing equipment and the
level of subscribed service. PSINet is not liable for any inability, failure or
mistake in implementing, enforcing, or monitoring the enforcement of the
specified policy.

PSINET-PROVIDED EQUIPMENT.

      (1) EQUIPMENT SPACE. Customer shall provide and maintain suitable
      Equipment Space meeting or exceeding the requirements set forth in the
      Specifications.

      (2) EQUIPMENT. The Equipment Space at each site specified by Customer
      will house Equipment owned by PSINet required for the Service. PSINet
      shall retain all right, title, and interest in the Equipment at all
      times. PSINet will provide Equipment at each site to provide the
      connection between Customer's network and the Telco circuit leading to
      the Network. The particular make and model of Equipment shall be selected
      for Customer by PSINet in its sole discretion. If PSINet determines in
      its sole reasonable judgment that the Equipment is defective, PSINet
      shall replace the defective Equipment at no cost to Customer. THE
      FOREGOING STATES PSINET'S SOLE OBLIGATION, AND CUSTOMER'S SOLE REMEDY,
      FOR ANY DEFECTIVE EQUIPMENT.





                          Schedule 5.4.1
                           Page 12 of 23

<PAGE>
      (3) EQUIPMENT ACCESS AND CONNECTION. The Equipment shall be maintained by
      PSINet or its subcontractors. Customer shall not allow its personnel or
      others on its premises to open the Equipment cabinets. PSINet will
      verbally authorize on an event-by-event basis individuals at Customer's
      location to open Equipment cabinets for appropriate routine and emergency
      reasons. Customer shall retain the right to disconnect the Equipment from
      its LAN at any time. PSINet reserves the right to shut down the Equipment
      at Customer's location in accordance with PSINet's emergency operating
      procedures with notification to Customer.

      (4) EQUIPMENT RELOCATION. PSINet is not responsible for Service
      disruptions caused by Customer's Equipment relocation requirements.

      (5) EQUIPMENT RETURN. Upon termination of the Service for any reason,
      Customer agrees immediately to allow the return of the Equipment to
      PSINet. PSINet retains all rights to recover possession of the Equipment
      from Customer.

LIMITED WARRANTIES.

      A. SERVICE. PSINET WARRANTS THAT THE SERVICE WILL OPERATE SUBSTANTIALLY
      IN CONFORMANCE WITH THE SPECIFICATIONS. PSINET MAKES NO OTHER WARRANTIES
      OF ANY KIND, WHETHER EXPRESSED, IMPLIED OR STATUTORY, INCLUDING, BUT NOT
      LIMITED TO, ANY IMPLIED WARRANTY OF MERCHANTABILITY, FITNESS OF THE
      SERVICE FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT OF ANY THIRD PARTY
      RIGHTS. CUSTOMER IS RESPONSIBLE FOR ASSESSING ITS OWN COMPUTER AND
      TRANSMISSION NETWORK NEEDS, AND THE RESULTS TO BE OBTAINED THEREFROM. USE
      OF ANY INFORMATION OBTAINED THROUGH THE SERVICE IS AT CUSTOMER'S RISK.
      PSINET SPECIFICALLY DENIES ANY RESPONSIBILITY FOR THE ACCURACY OR QUALITY
      OF INFORMATION OBTAINED THROUGH THE SERVICE.

      B. EQUIPMENT. PSINET REPRESENTS AND WARRANTS THAT DURING THE TERM OF THIS
      AGREEMENT IT WILL MAKE REASONABLE EFFORTS TO ENSURE THE EQUIPMENT
      OPERATES SUBSTANTIALLY IN CONFORMANCE WITH THE SPECIFICATIONS. ANY
      UNAUTHORIZED CHANGES TO OR INAPPROPRIATE USAGE OF THE EQUIPMENT, HOWEVER,
      WILL VOID THE FOREGOING WARRANTY. PSINET DOES NOT WARRANT THAT THE
      EQUIPMENT WILL BE ENTIRELY FREE FROM DEFECTS OR THAT ITS OPERATION WILL
      BE ERROR FREE. FURTHERMORE, CUSTOMER ACKNOWLEDGES THAT PSINET HAS MADE NO
      OTHER REPRESENTATION OR WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, WITH
      RESPECT TO THE CONDITION OR PERFORMANCE OF THE EQUIPMENT, OR ITS
      MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE.

      C. GENERAL. EACH PARTY ACKNOWLEDGES THAT IT HAS READ AND UNDERSTANDS THIS
      AGREEMENT AND AGREES TO BE BOUND BY ITS TERMS. EACH PARTY FURTHER
      WARRANTS THAT IT HAS FULL CORPORATE POWER AND AUTHORITY TO ENTER INTO AND
      DELIVER THIS AGREEMENT AND TO PERFORM ITS OBLIGATIONS HEREUNDER, AND THAT
      THE PERSON WHOSE SIGNATURE APPEARS BELOW IS DULY AUTHORIZED TO ENTER INTO
      THIS AGREEMENT ON BEHALF OF THAT PARTY.

LIMITATION OF LIABILITY. EXCEPT FOR CUSTOMER'S PAYMENT OBLIGATIONS HEREUNDER,
NEITHER PARTY SHALL BE LIABLE FOR DIRECT DAMAGES GREATER THAN THE SUM TOTAL OF
PAYMENTS MADE BY CUSTOMER TO PSINET DURING THE SIX (6) MONTHS IMMEDIATELY
PRECEDING THE EVENT FOR WHICH DAMAGES ARE CLAIMED. EXCEPT FOR THE FOREGOING,
PSINET SHALL HAVE NO LIABILITY TO CUSTOMER WITH RESPECT TO (I) ANY CLAIM, LOSS
OR DAMAGE OF ANY KIND OR NATURE WHATSOEVER INCLUDING THE ACTIVE OR PASSIVE
NEGLIGENCE OR STRICT LIABILITY OF PSINET FOR CLAIMS ARISING OUT OF OR IN
CONNECTION WITH THE SERVICE OR THE EQUIPMENT, WHETHER OR NOT KNOWN OR DISCLOSED
TO PSINET; (II) ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, PUNITIVE OR
CONSEQUENTIAL LOSSES OR DAMAGES RESULTING FROM THE DELIVERY, INSTALLATION,
MAINTENANCE, OPERATION OR USE OF THE SERVICE OR THE EQUIPMENT; (III) ANY ACT OR
OMISSION OF ANY OTHER ENTITY FURNISHING EQUIPMENT, PRODUCTS OR SERVICES TO




                          Schedule 5.4.1
                            Page 13 of 23

<PAGE>
CUSTOMER; (IV) ANY PERSONAL OR PROPERTY DAMAGES DUE TO THE LOSS OF STORED,
TRANSMITTED OR RECORDED DATA RESULTING FROM THE SERVICE OR THE EQUIPMENT, EVEN
IF PSINET HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH DAMAGES; AND (V) ANY LOSS
OR DAMAGES DUE TO THE FAULT OR NEGLIGENCE OF CUSTOMER OR ITS EMPLOYEES, AGENTS
OR REPRESENTATIVES.

IN NO EVENT SHALL EITHER PARTY BE LIABLE FOR ANY INDIRECT, INCIDENTAL,
EXEMPLARY, PUNITIVE OR OTHER CONSEQUENTIAL DAMAGES WHETHER OR NOT FORESEEABLE,
INCLUDING, BUT NOT LIMITED TO, DAMAGES FOR THE LOSS OF DATA, GOODWILL OR
PROFITS, ARISING OUT OF OR IN RELATION TO THIS AGREEMENT EVEN IF ADVISED
BEFOREHAND OF THE POSSIBILITY OF SUCH LIABILITY. THE PARTIES AGREE TO WORK IN
GOOD FAITH TO IMPLEMENT THE PURPOSES OF THIS AGREEMENT, BUT RECOGNIZE THAT THE
SERVICE COULD NOT BE MADE AVAILABLE UNDER THESE TERMS OR OTHER SIMILAR TERMS
WITHOUT A SUBSTANTIAL INCREASE IN COST IF PSINET WERE TO ASSUME A GREATER
DEGREE OF LIABILITY TO CUSTOMER.





                          Schedule 5.4.1
                           Page 14 of 23

<PAGE>
                    INTERNET REMOTE ACCESS SERVICE CUSTOMER
                              CONTRACT PROVISIONS


PSINET NETWORK USAGE.

      A. COMPLIANCE WITH LAW AND POLICY. Customer along with each End-User, has
      read and agrees to comply with PSINet's Net-Abuse Policy ("Policy") as
      currently set forth on PSINet's Web site (http://www.psi.net) and as the
      Policy may be modified by PSINet in its sole discretion from time to
      time. Any content, material, message or data made available or
      transmitted through an Account wherever it is sent from, viewed,
      received, or retrieved, that is in violation of (i) any local, state,
      federal or international law, regulation or treaty; (ii) the Policy; or
      (iii) any community standard or accepted Internet policy is prohibited.
      Any such violation may be deemed a material breach of this Agreement and
      PSINet may, in its sole discretion, disable or terminate an Account or
      the Service with written notice to Customer, but without any cure period.

      B. CUSTOMER-ONLY TRAFFIC. The right to use an Account is strictly limited
      to Customer only and does not extend to any other person, corporation or
      entity except for wholly-owned affiliates of Customer and those members
      of Customer's staff and consultants in the course of performing work for
      Customer.

      C. THIRD-PARTY TRAFFIC. Customer's End-Users may feed USENET News to a
      third party, but may not send any posting from that third party,
      including, but not limited to, electronic mail, back to the Network or
      the Internet through an Account. Any other third party traffic, including
      packet access and electronic mail, whether sent or received through
      Customer's facilities by or on behalf of a third party through the
      Service, is expressly prohibited.

CUSTOMER NETWORK AND FACILITIES. Customer shall remain responsible for
user/access security as well as access to its network or to the Network. PSINet
provides no user access security with respect to any of Customer or its
End-Users' facilities or facilities of others. PSINet will assist in network
security breach detection or identification, but shall not be liable for any
inability, failure or mistake in doing so.

"FIRST-LINE" SERVICE SUPPORT. Customer's MIS/Technical administrator or contact
is solely responsible for all first line customer support for End-Users. If
End-Users require additional support, only Customer's designated Help Desk or
MIS/Technical contact may request support directly from PSINet's Customer
Support Group (CSG).

10.   NO WARRANTIES. NEITHER PSINET, ITS AFFILIATES, DIRECTORS, EMPLOYEES AND
SUBCONTRACTORS WARRANT ANY CONNECTION TO, TRANSMISSION OVER, NOR RESULTS OR USE
OF, ANY NETWORK CONNECTION OR FACILITIES PROVIDED (OR FAILED TO BE PROVIDED)
UNDER THIS AGREEMENT. CUSTOMER IS RESPONSIBLE FOR ASSESSING ITS OWN COMPUTER
AND TRANSMISSION NETWORK NEEDS, AND THE RESULTS TO BE OBTAINED THEREFROM. USE
OF ANY INFORMATION OBTAINED VIA AN ACCOUNT IS AT CUSTOMER AND THEIR END-USER'S
RISK. PSINET SPECIFICALLY DENIES ANY RESPONSIBILITY FOR THE ACCURACY OR QUALITY
OF INFORMATION OBTAINED THROUGH THE ACCOUNTS. PSINET MAKES NO WARRANTIES OF ANY
KIND, WHETHER EXPRESSED, IMPLIED OR STATUTORY, INCLUDING, BUT NOT LIMITED TO,
ANY IMPLIED WARRANTY OF MERCHANTABILITY, FITNESS OF THE SERVICE FOR A
PARTICULAR PURPOSE AND NON-INFRINGEMENT OF ANY THIRD PARTY RIGHTS.

PSINET MAKES NO WARRANTY WITH RESPECT TO ANY SOFTWARE OR HARDWARE USED OR
PROVIDED BY PSINET IN CONNECTION WITH AN ACCOUNT. ANY PATENT, TRADEMARK, TRADE
SECRET OR WARRANTY INFRINGEMENTS, WHETHER ACTUAL OR ALLEGED, ARE THE DIRECT




                          Schedule 5.4.1
                          Page 15 of 23

<PAGE>
RESPONSIBILITY OF THE MANUFACTURER OF SAID HARDWARE OR SOFTWARE PRODUCT. PSINET
ASSUMES NO RESPONSIBILITY FOR ANY ACTIONS OR LIABILITIES ARISING FROM THE
POSSESSION OR USE OF THESE SOFTWARE OR HARDWARE PRODUCTS.

11.   LIMITATION OF LIABILITY. EXCEPT FOR CUSTOMER'S PAYMENT OBLIGATIONS
HEREUNDER, NEITHER PARTY SHALL BE LIABLE FOR DIRECT DAMAGES GREATER THAN THE
SUM TOTAL OF PAYMENTS MADE BY CUSTOMER TO PSINET DURING THE SIX (6) MONTHS
IMMEDIATELY PRECEDING THE EVENT FOR WHICH DAMAGES ARE CLAIMED. EXCEPT FOR THE
FOREGOING AND WITHOUT LIMITING ITS GENERALITY, PSINET SHALL HAVE NO LIABILITY
TO CUSTOMER OR ANY THIRD PARTY WITH RESPECT TO (I) ANY CLAIM, LOSS OR DAMAGE OF
ANY KIND OR NATURE WHATSOEVER INCLUDING THE ACTIVE OR PASSIVE NEGLIGENCE OR
STRICT LIABILITY OF PSINET FOR CLAIMS ARISING OUT OF OR IN CONNECTION WITH THE
INDIVIDUAL ACCOUNTS OR SERVICE OR RELATED HARDWARE OR SOFTWARE WHETHER OR NOT
KNOWN OR DISCLOSED TO PSINET; (II) ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
PUNITIVE OR CONSEQUENTIAL LOSSES OR DAMAGES RESULTING FROM THE DELIVERY,
INSTALLATION, MAINTENANCE, OPERATION OR USE OF THE INDIVIDUAL ACCOUNTS OR
SERVICE OR RELATED HARDWARE OR SOFTWARE; (III) ANY ACT OR OMISSION OF ANY OTHER
ENTITY FURNISHING HARDWARE, SOFTWARE OR SERVICES TO CUSTOMER; (IV) ANY PERSONAL
OR PROPERTY DAMAGES DUE TO THE LOSS OF STORED, TRANSMITTED OR RECORDED DATA
RESULTING FROM ANY INDIVIDUAL ACCOUNT, THE SERVICE OR RELATED HARDWARE OR
SOFTWARE, EVEN IF PSINET HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH DAMAGES;
AND (V) ANY LOSS OR DAMAGES DUE TO THE FAULT OR NEGLIGENCE OF CUSTOMER OR ITS
EMPLOYEES, AGENTS OR REPRESENTATIVES.

IN NO EVENT SHALL EITHER PARTY BE LIABLE FOR ANY INDIRECT, INCIDENTAL,
EXEMPLARY, PUNITIVE OR OTHER CONSEQUENTIAL DAMAGES WHETHER OR NOT FORESEEABLE,
INCLUDING, BUT NOT LIMITED TO, DAMAGES FOR THE LOSS OF DATA, GOODWILL OR
PROFITS, ARISING OUT OF OR IN RELATION TO THIS AGREEMENT EVEN IF ADVISED
BEFOREHAND OF THE POSSIBILITY OF SUCH LIABILITY. THE PARTIES AGREE TO WORK IN
GOOD FAITH TO IMPLEMENT THE PURPOSES OF THIS AGREEMENT, BUT RECOGNIZE THAT THE
INDIVIDUAL ACCOUNTS AND SERVICE COULD NOT BE MADE AVAILABLE UNDER THESE TERMS
OR OTHER SIMILAR TERMS WITHOUT A SUBSTANTIAL INCREASE IN COST IF PSINET WERE TO
ASSUME A GREATER DEGREE OF LIABILITY TO CUSTOMER OR OTHER THIRD PARTIES.





                          Schedule 5.4.1
                             Page 16 of 23

<PAGE>
MANAGED INTERNET SECURITY SERVICES
CUSTOMER CONTRACT PROVISIONS


      SECURITY SERVICES DEFINED. Customer desires certain additional security
      services offered by PSS (the "Security Services") as specified in the
      "RouteWalle(SM) Managed Perimeter Security Service Specifications," and
      the "SecureEnterpriseTM Enterprise-Wide Managed Security Service
      Specifications" which are collectively called the "Specifications" and
      are incorporated herein by reference. The Security Services are designed
      to provide certain access control techniques or information to Customer
      regarding its computer or computer network(s)' connection to the Network
      and the Internet. The addition of the Security Services for Customer as
      contemplated in this Agreement requires Customer to possess or acquire a
      Dedicated Internet Access Service (InterFrame, for the RouteWaller
      Security Service, and InterFrame or InterMAN, for the SecureEnterprise
      Security Service) from PSINet Inc. which connects Customer's host
      computer or local area network (LAN) to the PSINet wide-area network
      system (the "Network") and the Internet.

3.    SECURITY SERVICES POLICY CREATION AND IMPLEMENTATION.

      A. LIMITED SCOPE. WHILE PSS WILL ENDEAVOR TO PROVIDE AND/OR INSTALL
      EQUIPMENT OR CONSULTING AND IMPLEMENTATION EXPERTISE, AS APPLICABLE IN
      CONJUNCTION WITH THE SELECTED SECURITY SERVICE, CUSTOMER ACKNOWLEDGES
      THAT IT IS FAMILIAR WITH AND HAS HAD ADEQUATE OPPORTUNITY TO EVALUATE THE
      SECURITY SERVICE SELECTED AND THAT PSS WILL ONLY ULTIMATELY ACT UPON THE
      POLICY AND PROCEDURES ESTABLISHED AND COMMUNICATED IN WRITING BY CUSTOMER
      THROUGH ITS AUTHORIZED REPRESENTATIVES (SPECIFICALLY, THE "SECURITY
      OFFICERS" IDENTIFIED BY CUSTOMER IN THE SECURITY SERVICES ORDER FORM
      ("ORDER FORM") WHICH IS INCORPORATED HEREIN BY REFERENCE). ANY AND ALL
      SUCH WRITTEN COMMUNICATIONS SHALL BE APPENDED TO THIS AGREEMENT TO THE
      EXTENT AGREED UPON BY PSS.

      B. PROCEDURE.

      (1)   Customer shall delegate two Security Officers, a primary and a
            secondary. Security Officer names, phone numbers, fax numbers, and
            electronic mail addresses must be provided to PSS on the order
            form. PSS will take direction ONLY from these Security Officers for
            Security Service.

      (2)   Customer Security Officers must participate in an initial phone
            consultation with PSS's Security Coordinator.

      (3)   Customer requests for security provisions shall be made by
            electronic mail or fax to the designated PSS address to facilitate
            an audit trail.

      (4)   PSS Network Operations can be instructed by other Customer contacts
            to disable non-PSS access (for instance, MAE-East, MAE-West or CIX
            access).

      (5)   The Security Service can only be facilitated using PSS provided
            equipment at Customer's site and with Customer's employees. (6) PSS
            will ship PSS-owned equipment only to Customer's Security Officers
            for Customer either to install or have PSS personnel install.

4.    PSS-OWNED EQUIPMENT:





                          Schedule 5.4.1
                           Page 17 of 23

<PAGE>
      A. PSS-OWNED EQUIPMENT USAGE GRANTS. PSS hereby grants Customer a
      non-exclusive license to use the PSS-owned Equipment associated with the
      selected Security Service, along with any related user documentation,
      subject to the terms provided herein. Customer agrees and acknowledges
      that it has no right, title or interest in or to any of the PSS-owned
      Equipment, including, but not limited to, any related patents,
      trademarks, copyrights or other proprietary rights, except as
      specifically set forth herein.

      (1)   CUSTOMER MAY

            (a)      make copies of the software portions of the PSS-owned
                     Equipment for backup and archival purposes only, provided
                     that the software and all proprietary notices remain
                     intact.

            (b)      make copies of the PSS-owned Equipment's documentation,
                     provided that such documentation is copied in its entirety
                     and all proprietary notices remain intact.

      (2)   CUSTOMER MAY NOT

            (a)      rent, lend, sublicense or lease the PSS-owned Equipment to
                     another party.

            (b)      modify, disassemble, decompile or reverse engineer any
                     portion of the PSS-owned Equipment.

      B. PSS-OWNED EQUIPMENT SPACE. In order to allow for the Security Service,
      Customer shall, during the term of this Agreement, provide and maintain
      suitable Equipment Space. The Equipment Space will house the PSS-owned
      Equipment required for the Security Service. Customer shall retain the
      right to disconnect the PSS-owned Equipment from its LAN at any time;
      however such action will suspend the Security Service and any associated
      warranties provided by PSS.

      C. RELOCATION OF PSS-OWNED EQUIPMENT. Should Customer deem it necessary
      to have the PSS-owned Equipment relocated, Customer shall be responsible
      for moving the PSS-owned Equipment under PSS supervision. PSS shall not
      be responsible for any Security Service disruptions caused by the
      PSS-owned Equipment's relocation.

      D. USAGE OF PSS-OWNED EQUIPMENT. Should PSS provide PSS-owned Equipment
      to Customer (as will be labeled by PSS) for its use as part of this
      Agreement, title to the Equipment shall be and remain in PSS at all
      times, and Customer shall have no interest therein except as expressly
      provided under this Agreement. Customer assumes full responsibility for,
      and, in the event of lost or damaged PSS-owned Equipment, shall pay the
      replacement cost plus 5% to the nearest $10.00, plus any applicable
      shipping and handling charges. Upon termination of this Agreement,
      Customer shall immediately return all PSS-owned Equipment to PSS.

      E. REPROGRAMMING/REPAIRING PSS-OWNED ACCESS CONTROL CARDS. In the event
      Customer requires PSS to reprogram or repair an individual Access Control
      Card owned by PSS and already in use by Customer, Customer shall be
      responsible for all shipping fees to and from PSS and will incur a
      one-time handling fee of $25.00 per PSS-owned Access Control Card.

7.    CONFIDENTIAL INFORMATION.





                          Schedule 5.4.1
                           Page 18 of 23

<PAGE>
      A. ACKNOWLEDGMENT OF CONFIDENTIALITY. Each Party hereby acknowledges that
      it may be exposed to confidential and proprietary information belonging
      to the other party or relating to its affairs, including materials
      expressly designated or marked as confidential. Confidential Information
      does not include (i) information already known or independently developed
      by the recipient; (ii) information in the public domain through no
      wrongful act of the recipient, or (iii) information received by recipient
      from a third party who was free to disclose it.

      B. COVENANT NOT TO DISCLOSE. Each party hereby agrees that it shall not
      use, commercialize or disclose the other party's Confidential Information
      to any person or entity, except to its own employees or agents having a
      "need to know" such information in connection with the performance of
      this Agreement, and to such other recipients as the other party may
      approve in a signed, written document. Neither party shall alter or
      remove from any software, documentation or other Confidential Information
      of the other party (or any third party) any proprietary, copyright,
      trademark or trade secret legend. The parties' obligations of
      confidentiality under this Agreement shall survive termination of this
      Agreement for any reason.

8.    NON CIRCUMVENTION. During the term of this Agreement and for a period of
eighteen (18) months thereafter, Customer agrees not to hire, solicit, nor
attempt to solicit the services, of any employee or subcontractor of PSS, its
parent or affiliate companies, without PSS' prior written consent; provided,
however, that Customer is not prevented from employing such person who contacts
Customer on his or her own initiative and without any direct or indirect
solicitation by Customer. Violation of this provision shall, in addition to
other relief, entitle PSS or its parent company to assert liquidated damages
against Customer equal to one hundred fifty (150) percent of the solicited
person's annual compensation.

9.    CUSTOMER EQUIPMENT AND NETWORK. PSS IS NOT RESPONSIBLE TO CUSTOMER FOR
THE COST OR EXPENSE OF ADMINISTRATIVE, TECHNICAL, EMERGENCY AND SUPPORT
PERSONNEL AT CUSTOMER'S LOCATION NECESSARY FOR DEALING WITH PSS OR FOR
PROVIDING AND MAINTAINING CUSTOMER'S OWN COMPUTER EQUIPMENT AND NETWORK OR
INTERNET ACCESS. CUSTOMER SHALL CONTINUE TO BE RESPONSIBLE FOR USER/ACCESS
SECURITY AND NETWORK ACCESS TO ITS COMPUTER OR COMPUTER NETWORK(S). PSS WILL
ASSIST IN NETWORK SECURITY BREACH DETECTION OR IDENTIFICATION IN ACCORDANCE
WITH THE SECURITY SERVICE SELECTED AND INDUSTRY STANDARDS, BUT DOES NOT
GUARANTEE A SECURE COMPUTER OR COMPUTER NETWORK(S) OR ASSUME RESPONSIBILITY FOR
ANY INABILITY, FAILURE OR MISTAKE BY PSS IN PROVIDING SUCH ASSISTANCE.

10.   LIMITED PERFORMANCE WARRANTY ON PSS-OWNED EQUIPMENT. PSS REPRESENTS AND
WARRANTS THAT DURING THE TERM OF THIS AGREEMENT IT WILL MAKE REASONABLE EFFORTS
TO ENSURE THE PSS-OWNED EQUIPMENT USED IN CONNECTION WITH THE SECURITY SERVICE
OPERATES SUBSTANTIALLY IN CONFORMANCE WITH THE RELEVANT SPECIFICATIONS. ANY
UNAUTHORIZED CHANGES TO OR INAPPROPRIATE USAGE OF THE PSS-OWNED EQUIPMENT;
HOWEVER, WILL VOID ANY WARRANTY PROVIDED HEREUNDER.

PSS DOES NOT WARRANT THAT THE EQUIPMENT WILL BE ENTIRELY FREE FROM DEFECTS OR
THAT ITS OPERATION WILL BE ERROR FREE. FURTHERMORE, CUSTOMER ACKNOWLEDGES THAT
PSS HAS MADE NO OTHER REPRESENTATION OR WARRANTY OF ANY KIND, EXPRESS OR
IMPLIED, WITH RESPECT TO THE CONDITION OR PERFORMANCE OF THE EQUIPMENT, OR ITS
MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE. EXCEPT AS EXPRESSLY
PROVIDED ABOVE, PSS SHALL HAVE NO LIABILITY TO CUSTOMER WITH RESPECT TO (I) ANY
CLAIM, LOSS OR DAMAGE OF ANY KIND OR NATURE WHATSOEVER INCLUDING THE ACTIVE OR
PASSIVE NEGLIGENCE OR STRICT LIABILITY OF PSS FOR CLAIMS ARISING OUT OF OR IN
CONNECTION WITH THE EQUIPMENT, WHETHER OR NOT KNOWN OR DISCLOSED TO PSS; (II)
ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, PUNITIVE OR CONSEQUENTIAL LOSSES OR
DAMAGES RESULTING FROM THE DELIVERY, INSTALLATION, MAINTENANCE, OPERATION,
SERVICE OR USE OF THE EQUIPMENT EXCEPT AS SPECIFIED ABOVE; (III) ANY ACT OR
OMISSION OF ANY




                          Schedule 5.4.1
                            Page 19 of 23

<PAGE>
OTHER ENTITY FURNISHING EQUIPMENT, PRODUCTS OR SERVICES TO CUSTOMER; (IV) ANY
PERSONAL OR PROPERTY DAMAGES OR FOR LOSS OF STORED, TRANSMITTED OR RECORDED
DATA RESULTING FROM THE EQUIPMENT, EVEN IF PSS HAS BEEN ADVISED OF THE
POSSIBILITY OF SUCH DAMAGES; AND (V) ANY LOSS OR DAMAGES DUE TO THE FAULT OR
NEGLIGENCE OF CUSTOMER OR ITS EMPLOYEES, AGENTS OR REPRESENTATIVES.

EXCEPT AS EXPRESSLY SET FORTH ABOVE, PSS MAKE NO WARRANTIES WITH RESPECT TO:

      A. NON-PSS-OWNED EQUIPMENT. WITH RESPECT TO EQUIPMENT NOT OWNED BY PSS,
      PSS ASSIGNS TO CUSTOMER AND CUSTOMER MAY HAVE THE BENEFIT OF ANY
      MANUFACTURER'S WARRANTIES AND THE EQUIPMENT'S SERVICE AGREEMENTS (THE
      PERFORMANCE AND CHARACTER OF WHICH SHALL IN ALL CASES BE GOVERNED BY THE
      APPLICABLE THIRD PARTY LICENSE AGREEMENTS) TO THE EXTENT AVAILABLE AND
      ASSIGNABLE BY PSS; PROVIDED, HOWEVER, THAT CUSTOMER'S SOLE REMEDY FOR THE
      BREACH OF ANY SUCH WARRANTY, INDEMNIFICATION OR SERVICE AGREEMENT SHALL
      BE ACTIONS OR CLAIMS AGAINST THE MANUFACTURER, AND NOT AGAINST PSS, ITS
      PARENT COMPANY, THEIR DIRECTORS, EMPLOYEES AND AGENTS, NOR SHALL ANY SUCH
      BREACH HAVE ANY EFFECT WHATSOEVER ON THE RIGHTS AND OBLIGATIONS OF EITHER
      PARTY WITH RESPECT TO THIS AGREEMENT.

      B. SECURITY SERVICES. CUSTOMER IS RESPONSIBLE FOR ASSESSING ITS OWN
      COMPUTER AND TRANSMISSION NETWORK NEEDS, AND THE RESULTS TO BE OBTAINED
      THEREFROM. EXCEPT AS SPECIFICALLY PROVIDED IN THE SECTION ABOVE IN
      CONNECTION WITH THE RELATED PSS-OWNED EQUIPMENT, PSS MAKES NO WARRANTIES
      OF ANY KIND, WHETHER EXPRESSED, IMPLIED OR STATUTORY, WITH RESPECT TO THE
      SECURITY SERVICES, INCLUDING, BUT NOT LIMITED TO, ANY IMPLIED WARRANTY OF
      MERCHANTABILITY OR FITNESS OF THE SECURITY SERVICE FOR A PARTICULAR
      PURPOSE. PSS MAKES NO WARRANTY TO ANY THIRD PARTY WHO MAY RELY UPON THE
      SECURITY OF CUSTOMER'S COMPUTER OR COMPUTER NETWORK. C. BREACHES IN
      SECURITY. CUSTOMER AGREES THAT IN NO EVENT SHALL PSS, ITS PARENT COMPANY,
      THEIR AFFILIATES, DIRECTORS, EMPLOYEES AND AGENTS BE HELD LIABLE FOR ANY
      SECURITY BREACH EXPERIENCED BY CUSTOMER, ITS USERS OR OTHERS RELYING ON
      CUSTOMER'S COMPUTER OR COMPUTER NETWORK, WHETHER OR NOT RELATED TO OR
      ARISING FROM THE SECURITY SERVICE, OR FOR ANY FAILURE OF THE SECURITY
      SERVICE TO PERFORM IN ANY RESPECT.

11.   LIMITATION OF REMEDIES AND LIABILITIES. CUSTOMER AND PSS ACKNOWLEDGE THAT
THE FOLLOWING PROVISIONS REFLECT A FAIR ALLOCATION OF RISK:

      A. REMEDIES. CUSTOMER'S SOLE AND EXCLUSIVE REMEDIES FOR PSS'S DEFAULT
      HEREUNDER SHALL BE (I) TO OBTAIN THE REPAIR, REPLACEMENT OR CORRECTION OF
      THE DEFECTIVE EQUIPMENT TO THE EXTENT WARRANTED ABOVE OR, IF PSS
      REASONABLY DETERMINES THAT SUCH REMEDY IS NOT ECONOMICALLY OR TECHNICALLY
      FEASIBLE, (II) TO OBTAIN AN EQUITABLE PARTIAL OR FULL REFUND OF AMOUNTS
      PAID WITH RESPECT TO THE DEFECTIVE SECURITY SERVICE. CUSTOMER MAY
      TERMINATE THIS AGREEMENT AND RECOVER AMOUNTS PAID HEREUNDER WITH RESPECT
      TO THE INFRINGING SECURITY SERVICE, IN WHICH CASE, SUCH TERMINATION AND
      RECOVERY SHALL BE CUSTOMER'S SOLE AND EXCLUSIVE REMEDY IN RESPECT
      THEREOF.

      B. LIABILITIES. PSS SHALL NOT BE LIABLE FOR ANY AMOUNT EXCEEDING THE SUM
      OF FEES PAID FOR THE SECURITY SERVICE AT ISSUE DURING THE TWELVE (12)
      MONTHS PRECEDING SUCH CLAIM. IN NO EVENT SHALL EITHER PARTY BE LIABLE,
      WHETHER IN CONTRACT, TORT (INCLUDING NEGLIGENCE) OR OTHERWISE, FOR ANY
      PUNITIVE, SPECIAL, INDIRECT, INCIDENTAL OR OTHER CONSEQUENTIAL DAMAGES
      (INCLUDING LOST SAVINGS, PROFIT OR BUSINESS INTERRUPTION, LOSS OR
      MISAPPROPRIATION OF DATA, OR LOSS OR MISAPPROPRIATION OF CONFIDENTIAL OR
      PROPRIETARY INFORMATION, EVEN IF THE PARTY IS ADVISED IN ADVANCE OF SUCH
      POSSIBILITY) OF THE OTHER PARTY OR ANY THIRD PARTIES ARISING OUT OF OR IN
      RELATION TO THIS AGREEMENT. THE PARTIES AGREE TO WORK IN GOOD FAITH TO
      IMPLEMENT THE PURPOSES OF THIS AGREEMENT, BUT RECOGNIZE THAT THE SECURITY
      SERVICE TO BE PROVIDED BY PSS COULD NOT BE MADE AVAILABLE UNDER THESE




                          Schedule 5.4.1
                           Page 20 of 23

<PAGE>
      TERMS OR OTHER SIMILAR TERMS WITHOUT A SUBSTANTIAL INCREASE IN COST IF
      PSS WERE TO ASSUME A GREATER DEGREE OF LIABILITY TO CUSTOMER.

12. INSURANCE. Each party shall maintain adequate insurance protection covering
its respective activities hereunder, including coverage for statutory worker's
compensation, comprehensive general liability for bodily injury and tangible
property damage, as well as adequate coverage for vehicles, and for losses
attributable to fraudulent modification, damage or destruction of electronic
data.

13. EXPORT CONTROLS. Customer agrees and acknowledges that any export of the
Equipment used for the Security Services is subject to U.S. export control laws
and regulations. Customer shall not directly or indirectly transfer the
Equipment, or the documentation relating thereto, to any country or location
outside of the United States without obtaining the prior written consent of
PSS.

FORCE MAJEURE. Neither party shall be responsible for, and will not be
considered in breach or default of this Agreement on account of, any failure to
perform or delay in performance of any obligations hereunder caused by acts of
God, flood, fire, storm, war, public enemy, labor disturbances, including
strikes and lockouts, Equipment malfunction, failure of the Equipment
manufacturer to deliver Equipment, governmental regulations or interferences or
any other event not within the reasonable control of the responsible party and
which that party is unable to overcome by the exercise of reasonable diligence,
provided that such party will use its best efforts to resume normal
performance.





                          Schedule 5.4.1
                           Page 21 of 23

<PAGE>
PSINET INTERNETPAPER SERVICE
CUSTOMER CONTRACT PROVISIONS


SERVICE SUPPORT. Only Customer's MIS/Technical contact, designated below, may
request technical support assistance for the Option directly from PSINet's
Customer Support Group (CSG).

NO WARRANTY. PSINET PROVIDES THE OPTION ON AN "AS IS" BASIS. PSINET MAKES NO
OTHER WARRANTIES OF ANY KIND, WHETHER EXPRESSED, IMPLIED OR STATUTORY,
INCLUDING, BUT NOT LIMITED TO, ANY IMPLIED WARRANTY OF MERCHANTABILITY, FITNESS
OF THE OPTION FOR A PARTICULAR PURPOSE AND NON- INFRINGEMENT OF ANY THIRD PARTY
RIGHTS. CUSTOMER IS RESPONSIBLE FOR ASSESSING ITS OWN COMPUTER AND TRANSMISSION
NETWORK NEEDS, AND THE RESULTS TO BE OBTAINED THEREFROM. USE OF ANY INFORMATION
OBTAINED THROUGH THE OPTION IS AT CUSTOMER'S RISK. PSINET SPECIFICALLY DENIES
ANY RESPONSIBILITY FOR THE ACCURACY OR QUALITY OF INFORMATION OBTAINED THROUGH
THE OPTION.

LIMITATION OF LIABILITY. EXCEPT FOR CUSTOMER'S PAYMENT OBLIGATIONS HEREUNDER,
IN NO EVENT SHALL EITHER PARTY BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
EXEMPLARY, PUNITIVE OR OTHER CONSEQUENTIAL DAMAGES WHETHER OR NOT FORESEEABLE,
INCLUDING, BUT NOT LIMITED TO, DAMAGES FOR THE LOSS OF DATA, GOODWILL OR
PROFITS, ARISING OUT OF OR IN RELATION TO THIS ADDENDUM EVEN IF ADVISED
BEFOREHAND OF THE POSSIBILITY OF SUCH LIABILITY. THE PARTIES AGREE TO WORK IN
GOOD FAITH TO IMPLEMENT THE PURPOSES OF THIS ADDENDUM, BUT RECOGNIZE THAT THE
OPTION COULD NOT BE MADE AVAILABLE UNDER THESE TERMS OR OTHER SIMILAR TERMS
WITHOUT A SUBSTANTIAL INCREASE IN COST IF PSINET WERE TO ASSUME A GREATER
DEGREE OF LIABILITY TO CUSTOMER.









                          Schedule 5.4.1
                           Page 22 of 23

<PAGE>
PSINET CONSUMER WHOLESALE SERVICE
SUBSCRIBER CONTRACT PROVISIONS


TERMINATION OF ACCESS. Subscribers are required to comply with PSINet's
Net-Abuse Policy ("Policy") as currently set forth on PSINet's Web site
(HTTP://WWW.PSI.NET) and as the Policy may be modified by PSINet in its sole
discretion from time to time. Any content, material, message, or data made
available or transmitted through the Network, wherever it is sent from, viewed,
received, or retrieved, that is in violation of (i) any local, state, federal
or international law, regulation or treaty; (ii) the Policy; or (iii) any
community standard or accepted Internet policy is prohibited. In the event of
violation of the foregoing by any Subscriber, PSINet will advise Retailer
accordingly, and PSINet reserves the right, in its sole discretion, to
terminate such Subscriber's Access immediately with written notice to Retailer.

INDEMNIFICATION OF PSINET. SUBSCRIBER SHALL INDEMNIFY AND HOLD HARMLESS PSINET
AND PSINET'S DIRECTORS, OFFICERS, EMPLOYEES, AGENTS AND ADVISORS FROM AND
AGAINST ANY AND ALL CLAIMS OF OTHER PERSONS OR ENTITIES ARISING OUT OF ANY
MATERIAL, MESSAGE, DATA, INFORMATION OR OTHER CONTENT TRANSMITTED OR MADE
AVAILABLE BY SUBSCRIBER OR ARISING OUT OF OTHER ACTS OR OMISSIONS OF
SUBSCRIBER.





                          Schedule 5.4.1
                             Page 23 of 23

<PAGE>
                                SCHEDULE 5.4.2

                  PROVISIONS IN AGREEMENTS WITH IXC CUSTOMERS


Except as otherwise contemplated under Section 5.1 of the Joint Marketing and
Services Agreement to which this Schedule is attached (the "Marketing
Agreement"), IXC shall require that any IXC Customer to which Services are
provided enter into an agreement that provides, among other things, terms and
conditions reasonably consistent with the provisions of Schedule 5.4.1 to the
Marketing Agreement; PROVIDED, HOWEVER, that with respect to any IXC Customer
for which IXC is not in privity of contract with, IXC shall use reasonable best
efforts to cause the IXC Reseller to require that such IXC Customer enter into
an agreement that provides, among other things, terms and conditions reasonably
consistent with the provisions of Schedule 5.4.1 to the Marketing Agreement.
The parties shall be permitted to make appropriate substitutions to reflect the
identity and uniqueness of the providing party so long as the contract
provisions set forth on Schedule 5.4.1 remain in substantially the form
attached thereto and do not impose any greater liability, obligation or
commitment on the part of PSI. Such agreement shall also provide that, except
to the extent caused by PSI's gross negligence, recklessness or willful
misconduct, (i) such IXC Customer shall defend, indemnify and hold harmless PSI
and its respective directors, officers, employees and agents from any claim
asserted by any IXC Customer or any Third Party to or arising out of use by the
IXC Customer or Third Party of the Services or products provided hereunder,
(ii) that PSI shall not be liable to IXC Customer for indirect, consequential,
incidental or special damages even if advised of the possibility in advance,
and (iii) that PSI's liability for damages to any IXC Customer for any cause
whatsoever, regardless of form of action, shall be limited to the greater of
(A) $25,000 for each site provisioned for Services under this Agreement or (B)
the amounts paid by such IXC Customer for Services during the twelve (12) month
period preceding the incident giving rise to the claim for damages. The
foregoing requirements may be waived or modified with the consent of PSI and
shall be modified automatically to the extent PSI waives such provisions, or
imposes less restrictive provisions, on its customers under its standard terms
and conditions and normal business practices (including where exceptions are
routinely granted to customers), or for any other reseller or distributor. Each
Party agrees to consider such modifications to the foregoing requirements as
are reasonably required in light of market conditions. In situations in which
PSI enters into an agreement directly with the IXC Customer for the provision
of the Services, as contemplated under Section 5.4.2 of the Marketing
Agreement, PSI agrees to include corresponding provisions in its agreements
with IXC Customers for the benefit of IXC.





                          Schedule 5.4.2
                          Page 1 of 1

<PAGE>
                          SCHEDULE 6.2

                      PSI POINTS OF PRESENCE

                    PSINet Access Numbers

<TABLE>
<CAPTION>
         City                 STATE             PHONE #            V.34            ISDN           2B
<S>                     <C>               <C>                 <C>             <C>            <C>          <C>
Birmingham              AL                      205-942-9890        Yes             Yes
Birmingham              AL                      205-942-5809                        Yes           Yes
Huntsville              AL                      205-536-5920        Yes             Yes
Mobile                  AL                      334-660-0271        Yes             Yes
Little Rock             AR                      501-340-6400        Yes             Yes
Little Rock             AR                      501-372-2888                        Yes           Yes
Phoenix                 AZ                      602-640-6096        Yes             Yes
Phoenix                 AZ                      602-640-1072                        Yes           Yes
Tucson                  AZ                      520-620-6152        Yes             Yes
Bakersfield             CA                      805-322-2100        Yes             Yes
Barstow                 CA                      619-255-4044        Yes
Berkeley                CA                      510-848-1596                        Yes           Yes
Berkeley                CA                      510-848-1398        Yes             Yes
Burbank                 CA                      818-526-7749        Yes             Yes
Burbank                 CA                      818-526-7791                        Yes           Yes
Chico                   CA                      916-891-1055        Yes             Yes
Concord                 CA                      510-688-2363        Yes             Yes
Concord                 CA                      510-688-2367                        Yes           Yes
Fresno                  CA                      209-497-0200        Yes             Yes
Irvine                  CA                      714-450-0955        Yes             Yes
Irvine                  CA                      714-450-0255                        Yes           Yes
Los Angeles             CA                      213-625-8300        Yes             Yes
Los Angeles             CA                      213-622-3499                        Yes           Yes
Malibu                  CA                      310-317-8300        Yes
Malibu                  CA                      310-456-6171                        Yes           Yes
Mission Viejo           CA                      714-461-7915        Yes             Yes
Mission Viejo           CA                      714-461-7247                        Yes           Yes
Modesto                 CA                      209-524-0197        Yes             Yes
Mountain View           CA                      415-390-0900        Yes             Yes
Mountain View           CA                      415-428-0704                        Yes           Yes
Orinda                  CA                      510-254-7549        Yes             Yes
Orinda                  CA                      510-254-9675                        Yes           Yes
Pasadena                CA                      818-449-2859        Yes             Yes
Pasadena                CA                      818-449-1706        Yes             Yes
Pasadena                CA                      818-449-9750                        Yes           Yes
Sacramento              CA                      916-537-2901        Yes             Yes
Sacramento              CA                      916-536-3800        Yes
San Bernardino          CA                      909-824-9223        Yes             Yes
San Diego               CA                      619-230-1221        Yes             Yes
San Diego               CA                      619-232-1613                        Yes           Yes
San Francisco           CA                      415-442-4600        Yes             Yes
San Francisco           CA                      415-538-7866                        Yes           Yes
San Francisco           CA                      415-538-1594                        Yes           Yes
San Luis Obispo         CA                      805-545-5827        Yes             Yes
San Ramon               CA                      510-866-1791                        Yes           Yes
San Ramon               CA                      510-866-1879        Yes             Yes
Santa Ana               CA                      714-547-9231        Yes             Yes
Santa Ana               CA                      714-558-8232                        Yes           Yes
Santa Clara             CA                      408-980-8120        Yes             Yes
Santa Clara             CA                      408-727-1796                        Yes           Yes
Stockton                CA                      209-464-0899        Yes             Yes
Torrance                CA                      310-781-9329        Yes             Yes
Torrance                CA                      310-781-9216                        Yes           Yes
Van Nuys                CA                      818-781-1827        Yes             Yes
Van Nuys                CA                      818-781-2158                        Yes           Yes
Colorado Springs        CO                      719-594-2090        Yes             Yes
Colorado Springs        CO                      719-536-6900                        Yes           Yes
Denver                  CO                      303-713-4580        Yes             Yes
Denver                  CO                      303-713-6980                        Yes           Yes
Hartford                CT                      860-947-7656        Yes             Yes
Hartford                CT                      860-947-1200                        Yes           Yes
New Haven               CT                      203-497-8727        Yes             Yes
Stamford                CT                      203-316-2947        Yes             Yes
Wilton                  CT                      203-834-6730        Yes
Washington              DC                      202-296-1127        Yes             Yes
Washington              DC                      202-296-1388                        Yes           Yes
Wilmington              DE                      302-576-0500        Yes             Yes
Ft Lauderdale           FL                      954-971-5720        Yes             Yes
Ft Myers                FL                      941-477-5000        Yes             Yes
Jacksonville            FL                      904-355-1523        Yes             Yes
Miami                   FL                      305-471-6819        Yes             Yes
Miami                   FL                      305-471-8102                        Yes           Yes
Miami                   FL                      305-471-8978                        Yes           Yes
Orlando                 FL                      407-648-9426        Yes             Yes
Orlando                 FL                      407-648-9826                        Yes           Yes
Sarasota                FL                      941-362-0764        Yes             Yes
Sarasota                FL                      941-362-0864                        Yes           Yes
St Petersburg           FL                      813-826-0052        Yes             Yes
St Petersburg           FL                      813-826-3010                        Yes           Yes
Tallahassee             FL                      904-222-5078        Yes             Yes
Tampa                   FL                      813-276-9824        Yes             Yes
Tampa                   FL                      813-273-0923                        Yes           Yes
Winter Park             FL                      407-975-4600        Yes             Yes
Albany                  GA                      912-430-1000        Yes             Yes
Atlanta                 GA                      404-527-0300                        Yes           Yes
Atlanta                 GA                      770-577-1666                        Yes           Yes
Atlanta                 GA                      404-865-0110        Yes             Yes
Atlanta                 GA                      770-421-1576                        Yes           Yes
Atlanta                 GA                      770-421-0546        Yes             Yes
Augusta                 GA                      706-849-2280        Yes             Yes
College Park            GA                      404-762-5160        Yes             Yes
Des Moines              IA                      515-222-2140        Yes             Yes
Chicago                 IL                      312-565-9446                        Yes           Yes
Chicago                 IL                      312-565-4310                        Yes           Yes
Chicago                 IL                      312-240-3396        Yes             Yes
Schiller Park           IL                      847-671-4033        Yes             Yes
Urbana                  IL                      217-373-2680        Yes             Yes
Fort Wayne              IN                      219-452-1004        Yes             Yes
Indianapolis            IN                      317-842-7547        Yes             Yes
Indianapolis            IN                      317-576-0308                        Yes           Yes
South Bend              IN                      219-271-0326        Yes             Yes
Hutchinson              KS                      316-694-0036        Yes             Yes
Wichita                 KS                      316-337-0198        Yes             Yes
Wichita                 KS                      316-337-0095                        Yes           Yes
Louisville              KY                      502-584-1710        Yes             Yes
Louisville              KY                      502-588-9091                        Yes           Yes
Baton Rouge             LA                      504-928-2660        Yes             Yes
Baton Rouge             LA                      5040231-9963        Yes
New Orleans             LA                      504-366-0091        Yes             Yes
New Orleans             LA                      504-366-6003                        Yes           Yes
Lafayette               LA                      318-262-0039        Yes
Shreveport              LA                      318-686-2577        Yes             Yes
Boston                  MA                      617-927-3600        Yes             Yes
Boston                  MA                      617-450-6800                        Yes           Yes
Boston                  MA                      617-927-3800                        Yes           Yes
Springfield             MA                      413-846-0300        Yes             Yes
Billerica               MA                      508-439-6000        Yes             Yes
Billerica               MA                      508-262-9400                        Yes           Yes
Concord                 MA                      508-371-5300        Yes             Yes
Annapolis               MD                      410-268-0669        Yes
Baltimore               MD                      410-244-0719        Yes             Yes
Baltimore               MD                      410-244-0935                        Yes           Yes
Bel Air                 MD                      410-638-0219        Yes             Yes
Frederick               MD                      301-663-8153        Yes             Yes
Hagerstown              MD                      301-665-1216        Yes             Yes
Salisbury               MD                      410-341-0278        Yes             Yes
Portland                ME                      207-791-8300        Yes             Yes
Ann Arbor               MI                      313-998-2601        Yes             Yes
Bay City                MI                      517-667-6121        Yes             Yes
Centerline              MI                      810-574-0259        Yes
Detroit                 MI                      313-225-4099        Yes             Yes
Detroit                 MI                      313-259-0680        Yes             Yes
Flint                   MI                      810-768-7980        Yes
Grand Rapids            MI                      616-235-9246        Yes             Yes
Grand Rapids            MI                      616-235-1190                        Yes           Yes
Jackson                 MI                      517-783-0809        Yes             Yes
Kalamazoo               MI                      616-226-8593        Yes
Kalamazoo               MI                      616-226-8589        Yes             Yes
Lansing                 MI                      517-336-8936        Yes             Yes
Lansing                 MI                      517-267-9846        Yes             Yes
Midland                 MI                      517-837-1394        Yes             Yes
Pontiac                 MI                      810-475-4425        Yes
Royal Oak               MI                      810-614-3580        Yes             Yes
Royal Oak               MI                      810-435-2388        Yes             Yes
Royal Oak               MI                      810-435-5440        Yes             Yes
Saginaw                 MI                      517-771-0053        Yes
Duluth                  MN                      218-720-5960        Yes
St Paul                 MN                      612-223-7560        Yes
Minneapolis             MN                      612-317-9260        Yes             Yes
Minneapolis             MN                      612-317-9280                        Yes           Yes
Kansas City             MO                      816-235-7000        Yes             Yes
Kansas City             MO                      816-235-7300                        Yes           Yes
St Louis                MO                      314-516-0000        Yes             Yes
St Louis                MO                      314-622-0026                        Yes           Yes
Jackson                 MS                      601-956-2325        Yes             Yes
Jackson                 MS                      601-956-3883        Yes
Pascagoula              MS                      601-934-2180        Yes             Yes
Billings                MT                      406-247-3000        Yes
Asheville               NC                      704-253-0221        Yes
Charlotte               NC                      704-554-5680        Yes             Yes
Charlotte               NC                      704-554-5907                        Yes           Yes
Durham                  NC                      919-572-9895        Yes             Yes
Durham                  NC                      919-572-9891                        Yes           Yes
Fayetteville            NC                      910-323-9401        Yes             Yes
Greensboro              NC                      910-333-2366        Yes
Greensboro              NC                      910-574-0105                        Yes           Yes
Raleigh                 NC                      919-876-7279                        Yes           Yes
Raleigh                 NC                      919-876-8141        Yes             Yes
Rocky Mount             NC                      919-407-8042        Yes             Yes
Southern Pines          NC                      910-692-5130        Yes
Triangle Park           NC                      919-558-2121        Yes
Winston Salem           NC                      910-721-1212        Yes             Yes
Fargo                   ND                      701-271-6300        Yes             Yes
Lincoln                 NE                      402-458-2800        Yes
Manchester              NH                      603-644-0500        Yes
Atlantic City           NJ                      609-484-3516        Yes             Yes
Ewing                   NJ                      609-278-3268        Yes             Yes
Fairlawn                NJ                      201-794-1795        Yes             Yes
Hackensack              NJ                      201-343-8210        Yes             Yes
Moorestown              NJ                      609-667-0496        Yes             Yes
Morristown              NJ                      201-898-6758        Yes             Yes
Morristown              NJ                      201-898-6511                        Yes           Yes
Mt Holly                NJ                      609-265-8511        Yes             Yes
Newark                  NJ                      201-622-6100        Yes             Yes
Newark                  NJ                      201-645-0874        Yes             Yes
Perth Amboy             NJ                      908-442-6182        Yes             Yes
Princeton               NJ                      609-252-0301        Yes             Yes
Riverton                NJ                      609-786-1079        Yes             Yes
Trenton                 NJ                      609-631-0494        Yes             Yes
Vineland                NJ                      609-205-0040        Yes             Yes
Waverly                 NJ                      201-923-3113                        Yes           Yes
Albuquerque             NM                      505-246-9088        Yes             Yes
Las Vegas               NV                      702-382-6667        Yes             Yes
Reno                    NV                      702-322-9191        Yes             Yes
Albany                  NY                      518-436-3200        Yes
Buffalo                 NY                      716-888-1000        Yes             Yes
Buffalo                 NY                      716.843.0480        Yes             Yes
Buffalo                 NY                      716-843-0500                        Yes           Yes
Elmsford                NY                      914-789-8000        Yes             Yes
Garden City             NY                      516-227-5600        Yes             Yes
Garden City             NY                      516-357-2800        Yes
Islip                   NY                      516-468-5100        Yes             Yes
Islip                   NY                      516-468-2100                        Yes           Yes
Ithaca                  NY                      607-266-4600        Yes             Yes
Ithaca                  NY                      607-266-4500                        Yes           Yes
New York                NY                      212-328-4487        Yes             Yes
New York                NY                      212-709-3940                                      Yes
New York                NY                      212-709-3960                        Yes           Yes
New York                NY                      212-709-3980                        Yes           Yes
New York                NY                      212-440-8180                        Yes           Yes
Poughkeepsie            NY                      914-451-7800        Yes             Yes
Rochester               NY                      716-428-3700        Yes             Yes
Rochester               NY                      716-324-1000        Yes
Syracuse                NY                      315-448-4000        Yes             Yes
Troy                    NY                      518-270-7020        Yes                           No
White Plains            NY                      914-993-6000        Yes             Yes
White Plains            NY                      914-286-3520                        Yes           Yes
Akron                   OH                      330-374-6990        Yes             Yes
Akron                   OH                      330-253-9993                        Yes           Yes
Cincinnati              OH                      513-792-9299        Yes             Yes
Cincinnati              OH                      513-361-4100                        Yes           Yes
Cleveland               OH                      216-696-8236                        Yes           Yes
Cleveland               OH                      216-696-6331        Yes             Yes
Cleveland               OH                      216-622-7300        Yes             Yes
Columbus                OH                      614-442-9500        Yes             Yes
Columbus                OH                      614-222-0825                                      Yes
Dayton                  OH                      937-640-5321        Yes             Yes
Dayton                  OH                      937-220-6211                        Yes           Yes
Dublin                  OH                      614-228-7452        Yes             Yes
Dublin                  OH                      614-766-9196        Yes             Yes
Toledo                  OH                      419-246-2020        Yes             Yes
Youngstown              OH                      330-747-7070        Yes             Yes
Oklahoma City           OK                      405-270-0534        Yes
Tulsa                   OK                      918-445-2622        Yes             Yes
Medford                 OR                      541-776-4510        Yes             Yes
Portland                OR                      503-972-1495        Yes
Portland                OR                      503-972-1493                        Yes           Yes
Allentown               PA                      610-774-9866        Yes             Yes
Altoona                 PA                      814-949-7045        Yes             Yes
Altoona                 PA                      814-949-7046                        Yes           Yes
Carlisle                PA                      717-258-4462        Yes             Yes
Lancaster               PA                      717-871-6380        Yes
Harrisburg              PA                      717-770-2100        Yes             Yes
Harrisburg              PA                      717-770-1194                        Yes           Yes
Philadelphia            PA                      215-440-4205        Yes             Yes
Philadelphia            PA                      215-440-1274                        Yes           Yes
Pittsburgh              PA                      412-562-1103        Yes             Yes
Reading                 PA                      610-670-4650        Yes             Yes
Scranton                PA                      717-941-0113        Yes             Yes
State College           PA                      814-235-7670        Yes             Yes
York                    PA                      717-846-0086        Yes             Yes
Providence              RI                      401-276-2000        Yes
Charleston              SC                      803-853-4001        Yes             Yes
Columbia                SC                      803-254-2220        Yes             Yes
Greenville              SC                      864-288-1702        Yes             Yes
Greenville              SC                      864-288-4525                        Yes           Yes
Jackson                 TN                      901-661-9025        Yes             Yes
Knoxville               TN                      423-558-8400        Yes             Yes
Knoxville               TN                      423-588-0804                        Yes           Yes
Memphis                 TN                      901-371-2030        Yes             Yes
Memphis                 TN                      901-387-1793                        Yes           Yes
Nashville               TN                      615-385-4004        Yes             Yes
Nashville               TN                      615-385-7148                        Yes           Yes
Abilene                 TX                      915-738-3100        Yes             Yes
Amarillo                TX                      806-345-1500        Yes
Austin                  TX                      512-464-0011        Yes
Austin                  TX                      512-464-0008                        Yes           Yes
Dallas                  TX                      214-953-3199        Yes             Yes
Dallas                  TX                      214-979-2059                        Yes           Yes
Dallas                  TX                      214-860-1902                        Yes           Yes
El Paso                 TX                      915-545-7300        Yes             Yes
Ft Worth                TX                      817-258-9700        Yes
Houston                 TX                      713-767-1503        Yes             Yes
Houston                 TX                      713-567-0497                        Yes           Yes
Lubbock                 TX                      806-741-4400        Yes             Yes
Midland                 TX                      915-699-9500        Yes
San Angelo              TX                      915-481-8100        Yes
San Antonio             TX                      210-244-1900        Yes
Waco                    TX                      817-745-2000        Yes             Yes
Salt Lake City          UT                      801-264-7940        Yes
Salt Lake City          UT                      801-284-0480                        Yes           Yes
Danville                VA                      804-791-4306        Yes             Yes
Fredericksburg          VA                      540-374-0571        Yes             Yes
Herndon                 VA                      703-904-0600        Yes
Herndon                 VA                      703-904-7088                        Yes           Yes
Herndon                 VA                      703-904-9050                        Yes           Yes
Herndon                 VA                      703-742-0706                        Yes           Yes
Herndon                 VA                      703-742-5488                        Yes           Yes
Leesburg                VA                      703-779-1868        Yes             Yes
Lynchburg               VA                      804-528-0448        Yes             Yes
Norfolk                 VA                      804-455-8178        Yes             Yes
Richmond                VA                      804-755-7018        Yes             Yes
Richmond                VA                      804-672-0730                        Yes           Yes
Roanoke                 VA                      540-857-4320        Yes             Yes
Burlington              VT                      802-651-6600        Yes             Yes
Rutland                 VT                      802-786-7300        Yes             Yes
Seattle                 WA                      206-441-2203                        Yes           Yes
Seattle                 WA                      206-812-1155        Yes             Yes
Seattle                 WA                      206-443-0224        Yes             Yes
Seattle                 WA                      206-812-0396                        Yes           Yes
Tacoma                  WA                      206-552-2134        Yes             Yes
Green Bay               WI                      414-983-2080        Yes             Yes
Janesville              WI                      608-755-9420        Yes             Yes
Milwaukee               WI                      414-223-0220        Yes
Milwaukee               WI                      414-223-0222                        Yes           Yes
Charleston              WV                      304-353-7886        Yes             Yes
Morgantown              WV                      304-291-3256        Yes             Yes
Wheeling                WV                      304-233-1840        Yes             Yes
</TABLE>
                            Schedule 6.2
<PAGE>
                                  SCHEDULE 7.1


                      PRICES FOR OPTIONAL SERVICES

      The following are Optional Prices by Service, not including taxes and
postage, etc.:

WHOLESALE DIAL-UP INTERNET ACCESS                                 $$$$

      1.    Fulfillment (mailer, labeling,
            inserts, etc.)                            1.00/unit
      2.    Software, Netscape software               15.00/seat based upon an
                                                      initial order of 250,000
                                                      or more, orders below
                                                      this are priced at
                                                      $30.00/seat

We have a special situation that allows us to sell Netscape to you during July
for lower prices.

Please call for more details, Delivery to be required prior to July 31, 1997.

      3.    Diskette Duplication                      3.50/set
      4.    CD Duplication                            2.00/set
      5.    Printing                                  1.75/set
      6.    Customer Support for individuals          5.00/month/subscriber
      7.    Email services                            Prices available on July
                                                      15th
      8.    Usenet news                               10.00/each reader/month


DEDICATED INTERNET ACCESS SERVICE

      1.    Welcome Letters (setup and
            print merged)                             6.50/each, plus a one
                                                      time setup fee per
                                                      Reseller of 2,000/one
                                                      time

      2.    Materials                                 1.00/unit
      3.    Printing                                  1.75/set
      4.    Fulfillment (mailer, labeling,
            insert, etc.)                             1.00/unit
      5.    Usenet news                               10.00/reader/month
      6.    News Feeds                                195.00/month
      7.    RouteWaller Internet Security
            (w/5 free cards) plus a monthly charge    195.00/initial 250.00/MRC
      8.    Cold spare router                         100.00/month
      9.    SecureEnterprise                          4,000.00/Initial
            (w/5 free access control cards)           1,600.00/month
            Cold spare redundancy option              665.00/month
      10.   Additional Access Cards &
            authentication service                    15.00/month


LAN ON DEMAND

      1.    Welcome Letters (setup and print
            merged)                                   6.50/each, plus a one
                                                      time setup fee per if
                                                      Reseller or 2.00/one time




                           Schedule 7.1
                               Page 1 of 3

<PAGE>
      2.    Materials                                 1.00/unit
      3.    Printing                                  1.75/set
      4.    Fulfillment (mailer, labeling,
            insert, etc.)                             1.00/unit


INTERMAN                                              10.00/reader

      1.    Security Filtering                        195.00/setup plus
                                                      50.00/month MRC


WEB BUSINESS SERVICES

      1.    Web Start base site templates used        795.00/psi web setup


FIELD SERVICES, AVAILABLE ONLY IN IMAN CITIES

      1.    On-site Field Service visits              $1,000.00/day (billable
                                                      in  1/2  day increments)

DNS SERVICES

      1.    Additional Domain Name                    $100.00/each
      2.    Additional 1 IP network number            $100.00/each


VALUE ADDED RESELLER

      1.    PSI Master VAR agreement commissions      18%
            on Services
            (Not including any circuit charges or
            installation fees)
            Subject to an agreement on activity to be
            performed by both Parties


Network Monthly usage reports                         TBD

Off-hours Helpline Support (other than 8am to 8pm)    TBD





                           Schedule 7.1
                            Page 2 of 3

<PAGE>

                        APPENDIX 1 TO
                         SCHEDULE 7.1

                                        *

                  (CONFIDENTIAL AND PROPRIETARY TO PSINET, INC.)

                            RETAIL PRICE   IXC COST      MARGIN      MARGIN
                            ------------   ---------   ----------   --------
                             NRC   MRC    NRC    MRC   NRC    MRC   NRC  MRC
                             ---   ---    ---    ---   ---    ---   ---  ---
LAN-DIAL                $  145  $ 145 $  145  $  90  $ 0  $  55   $ 0% $  61%

LAN-ISDN                   295    295    295    135    0    160     0%  119%

InterFrame 56              295    395    295    175    0    220     0%  126%

InterFrame 128             995    895    995    795    0    100     0%   13%

InterFrame 256             995    995    995    895    0    100     0%   11%

InterFrame 512             995  1,595    995  1,095    0    500     0%   46%

InterFrame T1              995  1,995    995  1,395    0    600     0%   43%

InterMAN T1              3,000  1,200  3,000    800    0    400     0%   50%

InterMAN 4M              5,000  3,000  5,000  2,100    0    900     0%   43%

InterMAN 10M             5,000  4,000  5,000   2900    0  1,100     0%   38%

InterMAN 16M             5,000  8,000  5,000  5,750    0  2,250     0%   39%

InterMAN 25M             5,000 10,000  5,000  7,225    0  2,775     0%   38%

InterMAN T3 (SMDS)       5,000 12,000  5,000  8,395    0  3,605     0%   43%

InterMAN T3 (ATM)       15,000 12,000 15,000  8,395    0  3,605     0%   43%

PSIWebt T1                 250    100    250     80    0     20     0%   25%

PSIWebt 10M                250    500    250    400    0    100     0%   25%

PSIWebt T3                 250  3,000    250  2,500    0    500     0%   20%

InterRamp Remote
Access**                  0.00  19.95   0.00   9.00    0  10.95     0%  122%



**     Price is per unit



*    Confidential material has been omitted and filed separately with the 
     Securities and Exchange Commission.








                           Schedule 7.1
                             Page 3 of 3