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EXHIBIT 10.2





                       OBJECTIVE SYSTEMS INTEGRATORS, INC.
                   ENTERPRISE PROFESSIONAL SERVICES AGREEMENT
                            CONTRACT NO.: EPSA - 127


THIS ENTERPRISE PROFESSIONAL SERVICES AGREEMENT ("Agreement") is entered into as
of December 1, 1999 ("Effective Date"), between OBJECTIVE SYSTEMS INTEGRATORS,
INC. ("OSI"), and ADELPHIA COMMUNICATIONS CORPORATION.



1.       DEFINITIONS.

         (a)   Adelphia. Adelphia Communications Corporation and those of its
               --------
               Related Companies who affirmatively avail themselves of the
               benefits of this Agreement by executing and delivering an
               acknowledgment in the form of Exhibit 1. Adelphia Communications
               Corporation will be jointly and severally liable for the
               obligations of any Related Company under this Agreement.

         (b)   Related Entity. A corporation or other legal entity that directly
               --------------
               or indirectly, through one or more intermediaries, controls, is
               controlled by, or is under common control with, Adelphia. For
               purposes of the foregoing, the terms "control," "controlled by"
               and "under common control with" will mean the possession,
               directly or indirectly, of the power to direct or cause the
               direction of the management and policies of the entity, whether
               through ownership of voting securities, by contract or credit
               arrangement, as trustee or executor, or otherwise.

         (c)   Unless otherwise expressly noted in this Agreement, the terms in
               this Agreement will have the same meanings as set forth in the
               Enterprise License Agreement, Contract No. ELA - 321 (the
               "Enterprise License"), entered into between the parties
               contemporaneously with this Agreement.



2.       SERVICES
         --------

         (a)   Work Orders. OSI will provide to Adelphia the professional
               -----------
               services ("Services") described in one or more consecutively
               numbered work orders ("Work Orders"), executed from time to time
               by both parties and added as attachments to this Agreement.
               Services will be provided (1) in accordance with this Agreement
               and the applicable Work Order, and (2) either on a fixed price or
               time and materials basis as set forth in each Work Order. OSI
               will provide Services only under a valid Work Order. If the terms
               of a Work Order directly conflict with the terms of this
               Agreement, the terms of the Work Order will govern.

         (b)   Statements of Work. Each Work Order will have a Statement of Work
               ------------------
               attached ("SOW") which describes the Services, including all
               deliverable items and documentation ("Deliverables"), acceptance
               and performance criteria, schedule and pricing.

         (c)   Changes. Adelphia may terminate any Work Order under Section
               -------
               8(b). Services can be modified by notice from Adelphia. OSI will
               notify Adelphia of any increase in costs, delay in schedule or
               other consequence from that request, and the change will be
               implemented if the parties agree to a modification to the terms
               of the SOW.

         (d)   Delivery. Unless otherwise instructed, OSI will pack and ship
               --------
               Deliverables to Adelphia's address as noted below and according
               to OSI's standard practice, F.O.B. factory, with freight and
               insurance prepaid and invoiced to Adelphia. Adelphia will
               reimburse OSI for extra costs incurred to comply with Adelphia's
               special packing and shipping instructions. Adelphia has 10 days
               from receipt to verify that all Deliverables in a shipment have
               been received. OSI will replace missing Deliverables at no
               charge.

         (e)   Non-Exclusivity. This Agreement and any Work Order are not
               ---------------
               exclusive. Either party may represent others in any capacity,
               perform services for others or retain others to provide services
               to it.



3.       COORDINATION
         ------------

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         (a)   Project Managers. For each Work Order, the parties will designate
               ----------------
               single contacts as their project managers for the Services.
               Either party may change its project manager from time to time in
               its discretion by notice to the other party. All communications
               regarding a Work Order will be made through the project managers.


         (b)   Access. Adelphia will make available to OSI, on reasonable
               ------
               notice, such computer programs, data, interface information,
               other documentation and access to Adelphia's computers, systems
               and programs as are reasonably required by OSI to complete the
               Services. Delays in providing such items or access will delay OSI
               performance, and OSI will invoice Adelphia for the costs incurred
               by OSI in connection with the delay.

         (c)   Consultations, Reports. OSI will keep Adelphia reasonably
               ----------------------
               informed regarding its performance of the Services and will
               consult with Adelphia concerning the Services on a regular basis.


4.       ACCEPTANCE
         ----------

         Deliverables will be accepted if they substantially conform to the
         specifications set forth in the applicable SOW. Adelphia will be deemed
         to have accepted Deliverable if (1) Adelphia fails to provide notice of
         nonacceptance detailing one or more reproducible nonconformities within
         30 days of the installation date, or any later date set forth in the
         applicable SOW, in sufficient detail for OSI to reproduce and analyze
         the nonconformity, or (2) Adelphia makes productive use of the
         Deliverable at any time more than 30 days after the installation date.
         OSI will use its commercially reasonable efforts to remedy agreed
         nonconformities promptly after receiving that notice and on the new
         installation date, a new 30 day period will begin.



5.       PAYMENT
         -------

         (a)   Fees and Expenses. Work Orders will set forth the fees for
               -----------------
               Services. Pricing for time and materials Work Orders under this
               Agreement will be at rates equal to 75% of OSI's standard rates
               as in effect on the date that the Work Order is received. OSI
               will notify Adelphia of any proposed changes to OSI's standard
               rates. In addition to these fees, Adelphia will reimburse OSI for
               its reasonable and documented out-of-pocket expenses incurred in
               performing the Services, including, without limitation, coach
               class travel, business class lodging, automobile rental and meals
               Any travel related expenses will be in accord with Adelphia's
               then-current expense policies, as previously communicated to OSI
               in writing. Work Orders may include a total amount of fees and
               expenses, which OSI will not exceed without Adelphia's approval.

         (b)   Terms. If Services are on a time-and-materials basis, OSI will
               -----
               invoice Adelphia monthly for Services rendered, and if a not-to-
               exceed amount is specified, OSI will use its best efforts to
               complete the work described in the SOW for the not-to-exceed
               amount, and will provide advance notice to Adelphia if the work
               will not be completed for that amount. On receipt of that notice,
               Adelphia may determine whether to continue the work or accept the
               work in its then-current form and terminate further work under
               the SOW. If Services are on a fixed-price basis, OSI will invoice
               Adelphia according to the payment schedule in the Work Order.
               Invoiced amounts will be paid within 45 days of the date of the
               invoice. Payments will be made in immediately available U.S.
               funds, without withholding for taxes or other amounts. Late
               payments will accrue interest at the lesser of 1.5% per month or
               the maximum rate permitted by applicable law. Adelphia will
               reimburse OSI for all fees, costs and expenses (including,
               without limitation, attorneys' fees and court costs) incurred to
               collect amounts not timely paid.

         (c)   Taxes, Charges. Fees are exclusive of, and Adelphia will pay, all
               --------------
               sales, value-added, withholding or excise taxes, and other
               government fees and charges of any nature whatsoever other than
               taxes on the income of OSI ("Taxes"). If Adelphia is required to
               make any tax or other withholding on or in relation to payments
               otherwise due under this Agreement, it will be in addition to the
               amounts otherwise due. Taxes paid or payable by OSI will be
               invoiced to and paid by Adelphia. Adelphia will not be required
               to pay any sum to OSI under this subsection unless OSI (1) has
               actually paid or intends in good faith to pay an equal sum to a
               governmental entity, and (2) in good faith believes that
               applicable law requires the payment.



6.       RIGHTS IN WORK PRODUCT
         ----------------------

         (a)   Title. Except as expressly stated otherwise in a particular Work
               -----
               Order, Deliverables are not "works made for hire." OSI will own
               all right, title and interest in copyrights, trade secrets,
               patents, all other intellectual property and other rights
               relating to (1) the Deliverables, and (2) any information
               developed by OSI in the course of its performance.
               Notwithstanding the foregoing, OSI will not have any rights in
               proprietary

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               information or data first belonging to Adelphia before execution
               of the Work Order or provided by Adelphia to OSI under a Work
               Order.

         (b)   License to Adelphia. Except as expressly stated otherwise in a
               -------------------
               particular Work Order, OSI grants Adelphia a perpetual, non-
               exclusive, royalty-free, non-transferable license (without rights
               to sublicense) to use, duplicate, alter, maintain, enhance or
               otherwise modify Deliverables solely for Adelphia's own internal
               business uses and at its facilities. Adelphia will not market,
               resell, transfer, publish, disclose, display or otherwise make
               Deliverables available to third parties. Even if a Deliverable is
               intended to be combined with or operated as part of Adelphia's
               software or other work, it will remain a separate work and not
               part of a joint work.

         (c)   Effect of Sales, Divestitures, Mergers or Acquisitions. Expect as
               ------------------------------------------------------
               otherwise expressly stated otherwise in a Work Order, use of the
               Deliverables under this Agreement will extend (and is limited) to
               Adelphia, as from time to time constituted, and solely for its
               own internal uses. If Adelphia either directly or indirectly
               acquires, is acquired by, merges with or is otherwise combined in
               any way with AT&T, Time Warner Communications, Charter
               Communications, Comcast or any other owner-operator having an
               account base of 24 million unique subscribers or more (a
               "Competitive Merger"), then Adelphia's continued right to use the
               Deliverables will be limited only to those uses within its
               network as that uses and network existed on the business day
               before the acquisition, merger or combination takes place. Joint
               ventures or other similar activities, whether with one or more of
               the above, or otherwise, in which Adelphia controls the joint
               venture will not be deemed to be a Competitive Merger.



7.       CONFIDENTIALITY
         ---------------

         (a)   Confidential Information. In the course of their dealings, each
               ------------------------
               party will acquire Information about the other, including
               Information regarding business activities and operations,
               technical information and trade secrets of the party and its
               partners. Each party will hold in confidence any Information that
               it receives from the other party, not use that Information for
               purposes other than performance of this Agreement and not
               disclose the Information except to those employees and advisors
               who (1) have a need to know the same, and (2) are bound by law or
               have agreed in writing to maintain the Information in confidence.
               Information includes all nonpublic aspects of the OSI Software,
               including programs, methods of processing, program design and
               structure, the interaction and unique programming techniques
               employed, and performance data and test results. The term
               "Information" also includes the nonpublic plans of OSI and
               Vendors for new products and services, product improvements and
               marketing strategies. If a party discovers Information has been
               improperly used, disseminated or published, it will immediately
               notify the other party and take all reasonable actions to
               minimize the impact of the disclosure.

         (b)   Excluded Information. Even if marked as confidential, the
               --------------------
               obligations in Section 7(a) will not apply to Information
               generally available to or known to the public, known by the
               receiving party without obligation of confidentiality before the
               negotiations leading to this Agreement, independently developed
               by the receiving party outside the scope of this Agreement,
               lawfully disclosed to the receiving party without restriction by
               a third party having the right to make the disclosure or required
               to be publicly disclosed to a tribunal. In the case of required
               disclosures to tribunals, the receiving party will promptly
               notify the other party of the proceeding and fully assist the
               disclosing party to obtain protective orders maintaining the
               confidentiality of the Information.



8.       TERM , TERMINATION
         ------------------

         (a)   Term. This Agreement will commence on the Effective Date and
               ----
               continue until terminated under Section 8(c).

         (b)   Termination of Work Order. Services to be provided under a SOW
               -------------------------
               may be canceled on 45 days' notice by Adelphia, but Adelphia will
               pay for all Services provided by OSI through the date of
               cancellation at OSI's then-current time and materials rates (not
               to exceed the total amount due under that SOW) and all costs
               reasonably incurred by OSI in connection with that cancellation.

         (c)   Termination of this Agreement. This Agreement may be terminated
               -----------------------------
               (1) by either party on breach by the other party that remains
               uncured 30 days after notice specifying the breach with
               particularity, or (2) by either party for convenience with 30
               days notice after completion or termination by Adelphia under
               Section 8(b) of all outstanding Work Orders.

         (d)   Survival. On termination of this Agreement for any reason, the
               --------
               obligations of Adelphia to pay amounts

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               owed to OSI and to discharge any liability incurred before
               termination will survive, together with the provisions of the
               Sections 5, 6, 7, 9, 10, 11 and 12.

         (e)   Termination of Licenses. The licenses granted in Section 6(b)
               -----------------------
               will terminate (1) on any violation by Adelphia of Sections 5, 6
               or 7 remaining uncured for 30 days after notice from OSI, (2) as
               to any Related Entity, (a) six months following the date the
               entity ceases being a Related Entity if the entity has
               independently entered into a direct contract with OSI obligating
               it to observe all of the terms and conditions of this Agreement
               and limiting its use of the Deliverables to those uses in effect
               immediately prior to the date it ceased to be a Related Entity,
               or (b) on the date the entity ceases being a Related Entity if it
               has not entered into such a direct contractual relationship with
               OSI, or (3) on notice from Adelphia. On termination of a license,
               Adelphia will immediately destroy or return to OSI all copies of
               the Deliverables then in its possession or under its control, and
               Adelphia will have no continuing rights to the Deliverables.


9.       WARRANTIES
         ----------

         (a)   Limited Warranty. Except as expressly stated otherwise in a
               ----------------
               particular Work Order, OSI warrants that each Deliverable will
               substantially conform to the specifications in the applicable
               Work Order (1) for 120 days after it is first delivered to
               Adelphia if that delivery occurs during the first year that this
               Agreement is in effect, and (2) for 90 days after it is first
               delivered to Adelphia if that delivery occurs at any time after
               the first year that this Agreement is in effect.

         (b)   Year 2000. All Deliverables will, in their normal operation,
               ---------
               function as follows: (1) values for current dates before, during
               and after the Year 2000 will not cause interruptions in normal
               operation, (2) manipulations of date-related data will produce
               desired results before, during and after the year 2000 and
               management of stored dates will not cause problems, (3) date
               elements in interfaces and data storage will permit specification
               of century to eliminate date ambiguity, (4) for any date element
               represented without century, two digit years greater than or
               equal to 69 will convert to 19xx and two digit years less than 69
               will convert to 20xx, and (5) leap years will be properly
               processed and recognized. No warranty is provided for any date-
               related problems caused by any other software or any hardware
               connected to a Deliverable.

         (c)   Self-Help or Unauthorized Code. None of the Deliverables will
               ------------------------------
               contain any "Self-Help Code" or Unauthorized Code. As used in the
               Agreement, "Self-Help Code" includes any backdoor, time bomb,
               drop dead device or other software routine designed to disable a
               computer program automatically with the passage of time or under
               positive control of a person other than Licensee, but does not
               include any (a) authorization keys or other code designed to
               limit use of the OSI Software to specific purposes or on specific
               equipment, or (b) software routines designed to permit OSI (or
               any other person acting on authority of OSI) to obtain access to
               Adelphia's computer systems (e.g., remote access via modem) for
               purposes of authorized maintenance or technical support.
               "Unauthorized Code" means any virus, Trojan Horse, worm or other
               software routines designed to permit unauthorized access or to
               disable, erase or otherwise harm software, hardware or data. The
               term "Unauthorized Code" does not include Self-Help Code.

         (d)   Modifications. OSI makes no warranty as to any portion of a
               -------------
               Deliverable that is modified, altered or combined with any other
               software, by any party other than OSI.

         (e)   Warranty Limitations. SECTIONS 9(a), 9(b) AND 9(c) CONTAIN THE
               --------------------
               EXCLUSIVE WARRANTIES UNDER THIS AGREEMENT. EXCEPT FOR THAT
               WARRANTY, SERVICES AND DELIVERABLES ARE PROVIDED "AS-IS." NO
               OTHER WARRANTY, ORAL OR WRITTEN, IS EXPRESSED OR IMPLIED. OSI
               does not warrant that (1) the DELIVERABLE will perform in every
               operating environment, (2) the operation of the DELIVERABLE will
               be uninterrupted or error free, or (3) any defect or malfunction
               in the DELIVERABLE is correctable or will be corrected. OSI
               SPECIFICALLY DISCLAIMS THE IMPLIED WARRANTIES OF MERCHANTABILITY
               AND FITNESS FOR A PARTICULAR PURPOSE. The limited warranties in
               this Section will not apply to, and OSI will have no warranty
               obligation with respect to, any defect or malfunction (1) that
               results from improper modification or use by Adelphia, from
               hardware, software, interfacing or supplies other than those
               provided by OSI in the form provided by OSI, or from any cause
               other than ordinary use, or (2) where the nonconformity cannot be
               reproduced, where OSI is not provided with a the parameters,
               procedures or conditions which generate the problem in sufficient
               detail to permit it to isolate the code which causes the problem,
               or where OSI is not provided with all data files, rules, software
               and system access necessary to reproduce and analyze the problem.

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10.      LIMITATIONS, REMEDIES
         ---------------------

         (a)   Exclusive Remedies. Adelphia's sole remedy for a breach of the
               ------------------
               limited warranty provided in Section 9(a) will be for OSI to use
               its commercially reasonable efforts to bring the Deliverable into
               substantial conformity with applicable specifications, replace
               the Deliverable with an equivalent Deliverable substantially
               conforming with those specifications or, if OSI is unable to so
               restore the Deliverable or to provide an equivalent replacement,
               then for Adelphia to obtain a refund equal to the value of the
               non conforming portion of the Deliverable on its return to OSI.

         (b)   Aggregate Liability. NEITHER PARTY WILL BE LIABLE TO THE OTHER
               -------------------
               PARTY FOR DAMAGES IN EXCESS OF THE TOTAL AMOUNTS TO BE PAID TO
               OSI UNDER THIS AGREEMENT. THIS LIMITATION WILL (1) APPLY
               REGARDLESS OF THE FORM OF ACTION, WHETHER CONTRACT OR TORT,
               INCLUDING NEGLIGENCE AND STRICT LIABILITY, AND (2) NOT APPLY TO
               INDEMNITY UNDER SECTION 10 OR TO A BREACH OF SECTIONS 6 OR 7, OR
               TO LIABILITY FOR DEATH OR PERSONAL INJURY CAUSED BY THE GROSS
               NEGLIGENCE OR WILLFUL MISCONDUCT OF EITHER PARTY.

         (c)   Damages. NEITHER PARTY WILL BE LIABLE, REGARDLESS OF THE FORM OF
               -------
               ACTION, FOR LOST REVENUES, PROFITS OR SAVINGS, OR FOR INDIRECT,
               CONSEQUENTIAL, INCIDENTAL, SPECIAL OR PUNITIVE DAMAGES, EVEN IF
               THE PARTY HAS BEEN ADVISED OF THE POSSIBILITY OF THE DAMAGES.
               THIS SECTON 9(d) WILL NOT APPLY TO A BREACH OF THE OBLIGATIONS IN
               SECTION 7.


11.      INDEMNIFICATION
         ---------------

         (a)   Cross Indemnification. If an act or omission of one of the
               ---------------------
               parties, its officers, directors, employees, agents or
               representatives, causes or results in the (1) loss, damage to or
               destruction of property of the other party or third parties, or
               (2) death or injury to persons, including but not limited to
               employees of either party, then that party will indemnify, defend
               and hold the other party, its officers, directors, employees,
               agents and insurers harmless from and against all claims,
               actions, damages, demands, liabilities, costs and expenses,
               including reasonable attorneys' fees and expenses, (collectively,
               "Claims") resulting therefrom.

         (b)   Indemnification by OSI.
               ----------------------

               (1)   So long as Adelphia complies with the terms of Sections 5
                     and 7 of this Agreement, OSI will defend Adelphia against
                     any claims, and indemnify and hold Adelphia harmless
                     against any judgments, directly or indirectly resulting
                     from a claimed infringement or violation of any copyright,
                     patent, trademark, trade secret or other intellectual
                     property right with respect to the Deliverables. OSI will
                     have no liability for any such claims or judgments based
                     solely on (a) the actions of Adelphia, its employees or
                     agents, (b) use of a version, modification or adaptation of
                     a Deliverable, if the infringement would have been avoided
                     by the use of a then-current unaltered release of the
                     Deliverable, (c) use of Combined Software, if the
                     Deliverable operated independent of the Combined Software
                     is not the cause of the infringement, or (d) use of a
                     Deliverable in combination with any computer software,
                     hardware or data not delivered in that combination by OSI.

               (2)   On receiving notice of a claimed infringement, OSI may (a)
                     settle on terms that permit continued use of Deliverable,
                     (b) provide a reasonable substitute for the Deliverable,
                     (c) modify the Deliverable to be non-infringing, or (d) if
                     the foregoing remedies are not reasonably available, grant
                     Adelphia a credit for the depreciated value of the relevant
                     portion of the Deliverable (based on a 48 month life
                     beginning on the date of its delivery) and accept its
                     return.

               (3)   THIS SECTION PROVIDES ADELPHIA'S SOLE REMEDY FOR
                     INFRINGEMENT OF PATENTS, COPYRIGHTS OR OTHER INTELLECTUAL
                     PROPERTY RIGHTS.

         (c)   Indemnification by Licensee. Adelphia will defend OSI and its
               ---------------------------
               Vendors against any claims, and indemnify and hold OSI and its
               Vendors harmless against any judgments, directly or indirectly
               resulting from any claimed infringement or violation of any
               copyright, patent or other intellectual property right with
               respect to a Deliverable to the extent that Licensee Software or
               any of the acts described in Section 11(b)(1)(a) - (d) is the
               cause of the claimed infringement or violation.

         (d)   Cooperation. Notwithstanding the above, an indemnifying party is
               -----------
               under no obligation to defend or indemnify another party unless:
               (1) the indemnifying party has been promptly notified of the
               claim or suit and furnished with a copy of each pleading,
               communication, notice and other action relating to the claim or
               suit; (2) the indemnified party permits the indemnifying party,
               at the indemnifying party's expense, to assume sole

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               authority to conduct the trial or settlement of the claim or suit
               and any negotiations related to it; and (3) the indemnified party
               promptly provides all information and assistance reasonably
               requested by the indemnifying party in connection with the claim
               or suit.



12.      GENERAL
         -------

         (a)   Compliance with Export and Other Laws. The Deliverables and all
               -------------------------------------
               related rights, technical data and information are subject to
               export controls imposed by the U.S. Government. Adelphia will not
               transmit any Deliverable or information relating to a Deliverable
               outside of the United States or to any person or entity
               prohibited by the U.S. Government, whether by name, by
               citizenship, residency or otherwise, and will comply with all
               applicable export control restrictions. Each party, at its
               expense, will comply with all applicable laws, regulations, codes
               and ordinances. Neither party will be bound by any provision of
               this Agreement to the extent, but only to the extent, that it
               violates applicable law.

         (b)   Notices. Notices, consents, approvals and communications given
               -------
               under this Agreement will be (1) in writing, (2) in the English
               language, (3) sent by registered or certified mail, return
               receipt requested, postage prepaid, or by a courier service that
               obtains signed acknowledgement of receipt, to the address
               indicated below the signature block of this Agreement or to such
               other address as the affected party designates by prior notice,
               and (4) effective on the date received unless a later date is
               otherwise indicated in the notice, consent or communication.

         (c)   Assignment. This Agreement is not assignable, including by
               ----------
               operation of law, by either party, either in whole or in part,
               without the prior consent of the other party, which consent will
               not be unreasonably withheld; provided, however, that OSI may
               assign this Agreement without such consent in connection with any
               merger, acquisition or other combination with or by OSI, or in
               connection with the sale of all or substantially all of OSI's
               assets, whether directly or indirectly, provided the surviving
               entity or the acquiror of those assets, as applicable, agrees in
               writing to be bound by all of the terms and conditions of this
               Agreement. This Agreement will be binding on and inure to the
               benefit of the parties and their respective successors and
               permitted assigns.

         (d)   Governing Law. This Agreement will be governed by and construed
               -------------
               in accordance with the internal substantive laws of the State of
               California, excluding its choice of law principles. The United
               Nations Convention on Contracts for the International Sale of
               Goods will not apply.

         (e)   Arbitration. Any dispute, controversy or claim arising out of or
               -----------
               relating to this Agreement will be finally resolved by binding
               arbitration under the Rules of Arbitration of the American
               Arbitration Association in effect at the time of the arbitration
               ("AAA Rules").

               (1)   The venue of the arbitration will be Dallas, Texas. All
                     proceedings will be conducted in English and English
                     translations of all foreign language documents filed,
                     submitted or exchanged during the proceedings will be
                     supplied concurrently by the producing party. On reasonable
                     notice to the other party and the arbitration panel,
                     parties will be entitled to use expert and rebuttal
                     witnesses.

               (2)   Each party will pay its own fees and expenses incurred in
                     connection with the arbitration. Common expenses of the
                     arbitration (such as the fees and expenses of the
                     arbitrator) will be borne by the parties in such amounts or
                     proportions as the arbitrator may determine.

               (3)   The award of the arbitrator will be (a) in writing
                     (including reasons), and (b) final and binding on the
                     parties. Judgment upon the award may be entered and
                     enforced by any court of competent jurisdiction.

               (4)   In no event will the arbitrator award damages that are not
                     permitted under the express terms of this Agreement.

               (5)   Without prejudice to the AAA Rules, either party may apply
                     to any court of competent jurisdiction for such interim
                     relief as it considers appropriate, without the need to
                     post bond or other security, or if required, then the
                     minimum bond or other security permitted.

         (f)   Equitable Relief. Any breach of a party's obligations with
               ----------------
               respect to intellectual property rights will cause irreparable
               injury for which there are no adequate remedies at law. The
               aggrieved party will be entitled to equitable relief in addition
               to all other remedies that may be available, without the posting
               of bond or other security, or if required, then the minimum bond
               or security so required.

         (g)   Force Majeure. Neither party will be liable or held in default
               -------------
               for a failure or delay in performing its obligations under this
               Agreement, other than to make payment for amounts owing or to
               comply with Sections 5 and 7, due to any cause beyond its
               reasonable control, so long as the party takes all reasonable
               steps to avoid

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               and minimize the impact of such cause. A party suffering an event
               of force majeure will notify the other party as promptly as is
               reasonably possible regarding the nature of the event and its
               estimate of when the event will no longer apply.

         (h)   Entire Agreement. This Agreement and the Enterprise License
               ----------------
               Agreement of even date between the parties, including their
               respective Exhibits, constitutes the entire agreement between the
               parties regarding its subject matter and supersedes all prior
               communications, both oral and written, between the parties. This
               Agreement may not be modified, and no rights will be waived,
               except by an instrument in writing signed by a duly authorized
               representative of both parties. If the terms of this Agreement
               conflict with the terms of any of its Exhibits, the Exhibits will
               prevail. As used in this Agreement, the term "including" means by
               way of example and not limitation.

         (i)   Waivers. No waiver by a party of a breach of this Agreement will
               -------
               constitute a waiver of any other breach of the same or any other
               provision of this Agreement.

         (j)   Execution. This Agreement may be executed in multiple
               ---------
               counterparts, each of which will be deemed an original and all of
               which will constitute together one agreement. A counterpart
               delivered to a party by facsimile or similar electronic means
               will be deemed an original, equivalent in all respects to a
               manually executed counterpart.

         (k)   Intentional Risk Allocation. The provisions of this Agreement
               ---------------------------
               reflect an informed, voluntary allocation between the parties of
               the risks (known and unknown) that may exist in connection with
               this Agreement. This voluntary allocation was a material part of
               the bargain between the parties and the economic and other terms
               were negotiated and agreed to by the parties in reliance on that
               allocation.

         (l)   Independent Contractors. The parties are independent contractors.
               -----------------------
               Under no circumstances will the employees of one party be deemed
               the employees of the other for any purpose. This Agreement does
               not grant authority for either party to act for the other in an
               agency or other capacity, or to make commitments of any kind for
               the account of or on the behalf of the other.

         (m)   Severability. If any provision of this Agreement is determined to
               ------------
               be invalid or unenforceable, it will be deemed to be modified to
               the minimum extent necessary to be valid and enforceable. If it
               cannot be so modified, it will be deleted and the deletion will
               not affect the validity or enforceability of any other provision
               unless, as a result, the rights of either party are materially
               diminished or the obligations and burdens of either party are
               materially increased so as to be unjust or inequitable.

         (n)   Cumulative Remedies. Except as otherwise provided, the rights and
               -------------------
               remedies in this Agreement are cumulative and in addition to any
               other remedies available at law or equity.



IN WITNESS WHEREOF the parties have caused this Agreement to be executed by
their duly authorized representatives.



OBJECTIVE SYSTEMS INTEGRATORS, INC.          ADELPHIA COMMUNICATIONS CORPORATION




By:     /s/ Philip N. Cardman                By:    /s/ James P. Rigas
        --------------------------                  ----------------------------
Title:  Vice President                       Title: Vice President
        --------------------------                  ----------------------------
Date:   12/29/99                             Date:  12/29/99
        --------------------------                  ----------------------------


Address for Notices:

                                                                          Page 7
<PAGE>

<TABLE>
<CAPTION>

<S>                                                      <C>
Objective Systems Integrators, Inc.                      Adelphia Communications Corporation.
101 Park Way                                             Main at Water Street
Folsom, CA 95630                                         Coudersport, PA 16915
Attn:  Contracts Administration                          Attn:  President
Business Telephone:    (916) 353-2400                    Facsimile for Notices:  (814) 274-7098
Facsimile for Notices: (916) 353-0647
                                                         With a copy to:

                                                         Adelphia Business Solutions, Inc.
                                                         Main at Water Street
                                                         Coudersport, PA 16915
                                                         Attn:  General Counsel
                                                         Facsimile for Notices:  (814) 274-7782
</TABLE>

                                                                          Page 8
<PAGE>

                                   Exhibit 1
                                   ---------

                                Acknowledgement



THIS ACKNOWLEDGEMENT is made by the undersigned ("Adelphia") under the
Enterprise-Wide Professional Services Agreement (EPSA - 127), dated as of
December 20, 1999 ("Agreement"), between Adelphia Communications Corporation and
Objective Systems Integrators, Inc. ("OSI"). By execution below, the entity
listed agrees to be bound by the terms and conditions of the Agreement as though
a signatory thereto.


IN WITNESS WHEREOF, The Adelphia Related Entity and the OSI have caused this
Acknowledgement to be executed by their duly authorized representatives as of
the later of the dates indicated below.



__________________________________           OBJECTIVE SYSTEMS INTEGRATORS, INC.
ADELPHIA



By: ______________________________          By: ________________________________

Title:____________________________          Title:______________________________

Date: ____________________________          Date: ______________________________

                                                                          Page 9
<PAGE>

                                   Exhibit 2
                                   ---------

                                  Work Order


                           CONTRACT NO.: EPSA - 127
                              WORK ORDER NO:____

This Work Order is entered into as of ___________, ____ under the terms of the
Enterprise Professional Services Agreement (EPSA - 127), dated as of December
20, 1999 ("Agreement"), between the parties signing below. All capitalized terms
are defined in the Agreement unless otherwise defined in this Work Order.

Name of Project:


Date Professional Services are Expected to Begin:


OSI's Project Manager::


Adelphia's Project Manager:


Special Requirements:___________________________________________________________
________________________________________________________________________________
________________________________________________________________________________
________________________________________________________________________________
________________________________________________________________________________
________________________________________________________________________________
________________________________________________________________________________
________________________________________________________________________________
________________________________________________________________________________
________________________________________________________________________________
________________________________________________________________________________
________________________________________________________________________________
________________________________________________________________________________
________________________________________________________________________________
________________________________________________________________________________
________________________________________________________________________________
________________________________________________________________________________
________________________________________________________________________________
________________________________________________________________________________


The Statement of Work for this Project is attached and made a part of the
Agreement.



OBJECTIVE SYSTEMS INTEGRATORS, INC.            _________________________________


By: _______________________________            By: _____________________________

Title: ____________________________            Title: __________________________

Date: _____________________________            Date: ___________________________

                                                                         Page 10
<PAGE>

                           CONTRACT NO.: EPSA - 127
                              WORK ORDER NO:____
                               STATEMENT OF WORK



SCOPE OF WORK
-------------
     The Professional Services to be performed in accordance with this Agreement
are as follows:



SPECIFICATIONS
--------------



DELIVERABLES
------------
     OSI will deliver to Adelphia:



DEPENDENCIES
------------


PROJECT MILESTONES
------------------
     Milestone                              Date due to Adelphia
     ---------                              --------------------
     Milestone 1

     Milestone 2



ACCEPTANCE CRITERIA
-------------------


FEE WORK ORDER
--------------
     Fees will be billed on the following basis:

     __Firm Fixed Price ("FFP"); or

     __Time-and-Materials ("T&M")

     Check one line above. If FFP: such price will be $ _____________. OSI will
     invoice Adelphia according to the following schedule:

        On execution of this Agreement     $

        On delivery of first milestone     $

        On final delivery and acceptance   $

     Total Firm Fixed Price Amount  $

     If T&M: The aggregate time costs will not exceed $ ___________ without the
     approval of Adelphia, at the applicable hourly rates set forth below, and
     material and other expenses will not exceed $ ____________ for a total not
     to exceed $ ____________. OSI will invoice Adelphia monthly as set forth in
     the Agreement.



      Category                       Hourly Rate          Estimated No. of Hours
      --------                       -----------          ----------------------

      Program Manager            $ __________ per hour    ______________________

      Sr. Network Administrator  $ __________ per hour    ______________________

      Jr. Technician             $ __________ per hour    ______________________

                                                                         Page 11