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[LOGO OF CISCO SYSTEMS CAPITAL APPEARS HERE]

                                                                   Exhibit 10.30

                                                       Master Agreement No. 1047


                      MASTER AGREEMENT TO LEASE EQUIPMENT


THIS MASTER AGREEMENT TO LEASE EQUIPMENT (this "Agreement") is entered into as
of October 10, 1997 by and between CISCO SYSTEMS CAPITAL CORPORATION ("Lessor")
having its principal place of business at 3535 Garrett Drive, Santa Clara,
California 95054 and PSINET INC., a New York corporation ("Lessee"), having a
place of business at 510 Huntmar Park Drive, Herndon, CA 20170-5100. In
consideration of the covenants set forth herein, Lessor and Lessee have agreed
as follows:

                                 I. THE LEASE

1.1  LEASE OF EQUIPMENT. In accordance with the terms and conditions of this
     Agreement, Lessor shall lease to Lessee, and Lessee shall lease from
     Lessor, the units of personal property (individually, a "Unit," and,
     collectively, the "Equipment") described in the lease schedule(s) (each, a
     "Lease") to be entered into from time to time into which this Agreement is
     incorporated. Each Lease shall constitute a separate, distinct, and
     independent lease and contractual obligation of Lessee. Lessor or its
     assignee shall at all times retain the full legal title to the Equipment,
     it being expressly agreed by both parties that each Lease is an agreement
     of lease only. Each Lease shall be binding upon Lessor and Lessee from the
     date of its acceptance and execution by Lessor at its principal place of
     business.

1.2  TERM OF LEASE. The original term of each Unit shall commence on the date
     specified in the applicable Lease and, subject to Sections 3.3, 3.5 and
     5.14 below, shall terminate on the date specified in such Lease (the
     "Original Term"). Subject to Section 5.13, notwithstanding the foregoing,
     the Original Term for each Unit shall automatically extend for successive
     30-day periods after its expiration unless either party gives the other
     party written notice, at least 90 days prior to the expiration of the
     Original Term or the then extended term, as the case may be, of its intent
     not to so extend the applicable Lease. Except as specifically provided in
     Section 5.14, no Lease may be terminated by Lessor or Lessee, for any
     reason whatsoever, prior to the end of the Original Term or any extended
     term.

1.3  RENTAL PAYMENTS. Lessee shall pay Lessor rent ("Rent") for each Unit in the
     amounts and at the times specified in the Lease. The Lease Term for each
     Unit shall commence on the Acceptance Certificate Execution Date and shall
     continue for the period specified in the Lease, unless otherwise extended
     or terminated pursuant to Section 1.2 or 5.14. The Lease Term as to any
     Unit may not be terminated by Lessee unless otherwise expressly provided in
     the Lease. All rental and other amounts payable by Lessee to Lessor
     hereunder shall be paid to Lessor at the address specified above, or at
     such other place as Lessor may designate in writing to Lessee from time to
     time.

1.4  RETURN OF EQUIPMENT. Subject to Section 5.13, upon expiration of the
     Original Term of a Unit, Lessee shall immediately return such Unit to
     Lessor as provided in Section 3.3 below. Subject to Section 5.13, and
     except as provided in Section 1.2 above, should Lessee not return any Unit
     at the end of its Original Term, Lessee shall continue to pay Rent to
     Lessor with respect to such Unit in the sum and on the due dates set out in
     the applicable Lease, as a month-to-month lease, until such Unit is
     returned by Lessee. If Lessee fails to return any of the Equipment upon
     demand therefor by Lessor, Lessee shall pay Lessor, as the measure of
     Lessor's damages, the Casualty Value (as defined in the applicable Lease)
     of such Equipment.

             II. DISCLAIMERS AND WARRANTIES; INTELLECTUAL PROPERTY

2.1  DISCLAIMERS; WARRANTIES. Lessee represents and acknowledges that each Unit
     is of a size, design, capacity and manufacture selected by it, and that it
     is satisfied that each Unit is suitable for its purposes. LESSOR SUPPLIES
     THE EQUIPMENT AS IS, AND, NOT BEING THE MANUFACTURER OF THE EQUIPMENT, THE
     MANUFACTURER'S AGENT OR THE SELLER'S AGENT, MAKES NO WARRANTY OR
     REPRESENTATION, EITHER EXPRESS OR IMPLIED, AS TO THE MERCHANTABILITY,
     FITNESS FOR ANY PARTICULAR PURPOSE, DESIGN OR CONDITION OF THE EQUIPMENT,
     LESSOR SHALL NOT BE RESPONSIBLE FOR ANY LOSS OR DAMAGE RESULTING FROM THE
     INSTALLATION, OPERATION OR OTHER USE, OR DEINSTALLATION OF THE EQUIPMENT,
     INCLUDING, WITHOUT LIMITATION, ANY DIRECT, INDIRECT, INCIDENTAL OR
     CONSEQUENTIAL DAMAGE OR LOSS. Lessee shall look solely to the manufacturer
     or the supplier of Equipment for correction of any problems that may arise
     with respect thereto, and all warranties made by the manufacturer or such
     supplier are, to the degree possible, hereby assigned to Lessee for the
     term of the applicable Lease. To the extent any such warranty requires
     performance of any kind by the beneficiary of the warranty, Lessee shall
     perform in accordance therewith.

2.2  INTELLECTUAL PROPERTY. Except as otherwise expressly provided in each
     Lease, LESSOR MAKES NO WARRANTIES OR REPRESENTATIONS WHATSOEVER WITH
     RESPECT TO THE INTELLECTUAL PROPERTY RIGHTS, INCLUDING, WITHOUT LIMITATION,
     ANY PATENT, COPYRIGHT AND TRADEMARK RIGHTS, OF ANY THIRD PARTY WITH RESPECT
     TO THE EQUIPMENT, WHETHER RELATING TO INFRINGEMENT OR OTHERWISE Lessor
     shall, at Lessee's cost and expense, exercise, when requested by Lessee,
     rights of indemnification, if any, for patent, copyright or other
     intellectual property infringement obtained from the manufacturer under any
     agreement for or relating to the purchase of the Equipment. If notified
     promptly in writing of any action brought against Lessee based on a claim
     that the Equipment infringes a United States patent, copyright or other
     intellectual property right, Lessor shall promptly notify the manufacturer
     thereof for purposes of exercising, for the benefit of Lessee, Lessor's
     rights with respect to such claim under any such agreement.

                           III. COVENANTS OF LESSEE

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3.1  Payments Unconditional; Tax Benefits; Acceptance. EACH LEASE SHALL BE A NET
     LEASE, AND SUBJECT TO SECTION 5.3 HEREOF, LESSEE'S OBLIGATION TO PAY ALL
     RENT AND OTHER SUMS THEREUNDER, AND THE RIGHTS OF LESSOR IN AND TO SUCH
     PAYMENTS, SHALL BE ABSOLUTE AND UNCONDITIONAL, AND SHALL NOT BE SUBJECT TO
     ANY ABATEMENT, REDUCTION, SETOFF, DEFENSE, COUNTERCLAIM, INTERRUPTION,
     DEFERMENT OR RECOUPMENT, FOR ANY REASON WHATSOEVER. It is the intent of
     Lessor, and an inducement to Lessor, to enter into each Lease, to claim all
     available tax benefits of ownership with respect to the Equipment subject
     thereto. Lessee acknowledges and represents that (a) no right, title or
     interest in such Equipment has been or is intended to be passed to Lessee,
     other than the right to maintain possession of and use of such Equipment
     for the Original Term of such Lease, conditioned on Lessee's performance of
     the terms and conditions of such Lease, (b) Lessee has not taken and will
     not, at any time during the Original Term of such Lease, take any action
     which could cause Lessor to lose any tax benefits of ownership, and (c) the
     Casualty Value of each Unit (as defined in the applicable Lease) includes
     an amount which provides for Lessor's recovery of the loss of such tax
     benefits. Lessee's acceptance of the Equipment subject to a Lease shall be
     conclusively and irrevocably evidenced by Lessee executing a Acceptance
     Certificate with respect to such Equipment, and, upon acceptance, such
     Lease shall be noncancellable for its Original Term except as set forth in
     Section 5.14. Any nonpayment of Rent or other amounts payable under any
     Lease shall result in Lessee's obligation to promptly pay Lessor as
     additional Rent on such overdue payment, for the period of time during
     which it is overdue (without regard to any grace period), interest at a
     rate equal to the lesser of (a) 14% per annum, or (b) the maximum rate of
     interest permitted by law (the "Default Rate").

3.2  USE OF EQUIPMENT. Lessee shall use the Equipment solely in the conduct of
     its business, in a manner and for the use contemplated by the manufacturer
     thereof, and in material compliance with all laws, rules and regulations of
     every governmental authority having jurisdiction over the Equipment or
     Lessee and with the provisions of all policies of insurance carried by
     Lessee pursuant to Section 3.6 below; provided, however, Lessee shall have
     the right to allow third parties, under Lessees supervision, to use the
     Equipment, so long as Lessee shall retain uninterrupted possession and
     control of the Equipment. Lessee shall pay all costs, expenses, fees and
     charges incurred in connection with the use and operation of the Equipment.

3.3  DELIVERY; INSTALLATION; RETURN; MAINTENANCE AND REPAIR; INSPECTION. Lessee
     shall be solely responsible, at its own expense, for (a) the delivery of
     the Equipment to Lessee, (b) the packing, rigging and delivery of the
     Equipment back to Lessor, upon expiration of the Original Term, in good
     repair, condition and working order, ordinary wear and tear excepted, at
     the location(s) within the continental United States specified by Lessor,
     and (c) the installation at Lessees premises, de-installation, maintenance
     and repair of the Equipment. During the term of the applicable Lease,
     Lessee shall ensure that each Unit is covered by a maintenance agreement,
     to the extent available, with the manufacturer of such Unit or such other
     party, reasonably acceptable to Lessor. Lessee shall, at its expense, keep
     the Equipment in good repair, condition and working order, ordinary wear
     and tear excepted, and, subject to Section 5.13, at the expiration of the
     Original Term, or any renewal term, with respect to any of the Equipment,
     have such Equipment inspected and certified acceptable for maintenance
     service by the manufacturer. In the event any of the Equipment, upon its
     return to Lessor, is not in good repair, condition and working order,
     ordinary wear and tear excepted, Lessee shall be obligated to pay Lessor
     for the out-of-pocket expenses Lessor incurs in bringing such Equipment up
     to such status, but not in excess of the Casualty Value (as defined in the
     applicable Lease) for such Equipment, promptly alter its receipt of an
     invoice for such expenses. Lessor shall be entitled to inspect the
     Equipment at Lessee's location at reasonable times and upon prior written
     request.

3.4  TAXES. Lessee shall be obligated to pay, and hereby indemnifies Lessor and
     its successors and assigns against, and holds each of them harmless from,
     all license fees, assessments, and sales, use, property, excise and other
     taxes and charges, other than those measured by Lessor's net income, now or
     hereafter imposed by any governmental body or agency upon or with respect
     to any of the Equipment, or the possession, ownership, use or operation
     thereof, or any Lease or the consummation of the transactions contemplated
     in any Lease or this Agreement. Notwithstanding the foregoing, Lessor shall
     file all required personal property tax returns, and shall pay all personal
     property taxes payable, with respect to the Equipment, Lessee shall pay to
     Lessor, as additional rental, the amount of all such personal property
     taxes within 15 days of its receipt of an invoice for such taxes.
     Notwithstanding anything to the contrary in this Agreement or any Lease,
     including without limitation, Sections 3.1, 3.4 and 3.7 hereof, Lessee
     makes no representation or warranty whatsoever to Lessor as to the tax
     treatment of this Lease under any applicable laws, rules or regulations.

3.5  LOSS OF EQUIPMENT. Lessee shall bear the entire risk of the Equipment being
     lost, destroyed or otherwise rendered permanently unfit or unavailable for
     use from any cause whatsoever (an "Event of Loss") after it has been
     delivered to a common carrier for shipment to Lessee. If an Event of Loss
     shall occur with respect to any Equipment (or any Unit), Lessee shall
     promptly notify Lessor in writing of such Event of Loss and of all details
     with respect thereto, and shall, within thirty (30) days of such event, at
     Lessees option, (a) place such Equipment (or Unit) in good repair,
     condition and working order, or (b) replace such Equipment (or any Unit)
     with like personal property in good repair, condition and working order and
     transfer title to such replacement property to Lessor whereupon such
     property shall be subject to the applicable Lease and be deemed Equipment
     for purposes thereof, or (c) pay Lessor an amount equal to the sum of (i)
     all Rent accrued to the date of such payment, plus (ii) the Casualty Value
     of such Equipment (or Unit) as set forth in the applicable Lease, whereupon
     this Agreement and the applicable Lease shall terminate with respect to
     such Equipment (or any such Unit) for which such payment is received by
     Lessor. Upon payment of the amount set forth in (c), the Rent for such
     Lease shall be reduced proportionately. Any insurance proceeds received
     with respect to the Equipment (or any Unit) shall be applied, in the event
     option (c) is elected, in reduction of the then unpaid obligations of
     Lessee to Lessor, including the Casualty Value, if not already paid by
     Lessee, or, if already paid by Lessee, to reimburse Lessee for such
     payment, or, in the event of option (a) or (b) is elected, to pay or
     reimburse Lessee for the costs of repairing, restoring or replacing the
     Equipment (or any Unit) upon receipt by Lessor of evidence, reasonable
     satisfactory to Lessor, that such repair, restoration or replacement has
     been completed, and an invoice therefor.

3.6  INSURANCE. Lessee shall obtain and maintain for the entire term of each
     Lease, at its own expense, property damage and liability insurance and
     insurance against loss or damage to the Equipment subject to such Lease
     including, without limitation, loss by fire (including so-called extended
     coverage), theft and such other risks of loss as are normally maintained on
     equipment of the type leased hereunder by company's carrying on the
     business in which Lessee is engaged, in such amounts, in such form and with
     such insurers as shall be reasonably satisfactory to Lessor. Each insurance
     policy will name Lessee as insured and Lessor as an additional insured and
     loss payee thereof as Lessor's interests may appear, and shall provide that
     it may not be canceled or materially altered without at least 30 days prior
     written notice thereof being given to Lessor or its successors and assigns.

3.7  INDEMNITY. Except with respect to the gross negligence or willful
     misconduct of Lessor, Lessee hereby indemnifies, protects, defends and
     holds harmless Lessor and its successors and assigns, from and against any
     and all claims, demands, actions, suits, and proceedings, losses costs,
     expenses, damages and liabilities, including, without limitation,
     reasonable attorneys' fees and costs (collectively, "Claims"), arising out
     of, connected with, or resulting from this Agreement, any Lease or any of
     the Equipment, including, without limitation, the manufacture, selection,
     purchase, delivery, possession, condition, use, operation, or return of the
     Equipment. Each of the parties shall 

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     give the other prompt written notice of any Claim of which it becomes
     aware. The provisions of this Section 3.7 shall survive the expiration or
     termination of this Agreement or any Lease until the expiration of any
     applicable statute of limitations.

3.8  PROHIBITIONS RELATED TO EQUIPMENT. Without the prior written consent of
     Lessor, which consent as it pertains to subsections (a) and (c) below shall
     not be unreasonably withheld, Lessee shall not: (a) sublease any of the
     Equipment (provided that Lessee may, without the prior written consent of
     Lessor, permit any Affiliate (defined below) of Lessee to use any of the
     Equipment in the ordinary course of its business); (b) create or incur, or
     permit to exist, any lien or encumbrance with respect to Lessee interest in
     any of the Equipment, or any part thereof; (c) move any of the Equipment
     from the location specified in the Lease, except within the continental
     limits of the United States if Lessee gives Lessor 30 days prior written
     notice thereof; (d) permit any of the Equipment to be moved outside the
     continental limits of the United States. For purposes of this Agreement,
     the term Affiliate" shall mean (i) any corporation which controls, is
     controlled by, or under common control with Lessee, (ii) any corporation
     resulting from the merger or consolidation of Lessee, or (iii) any entity
     which acquires all of the assets of Lessee as a going concern. For purposes
     of this Section 3.8, the term "control" shall mean the power to direct the
     management of the relevant entity.

3.9  IDENTIFICATION. Lessee shall place and maintain permanent markings provided
     by Lessor on each Unit evidencing ownership, security and other interests
     therein, as specified from time to time by Lessor. Lessee shall not place
     or permit to be placed on any Unit any other markings that might indicate
     any other ownership or security interest in such Unit. Any markings on any
     Unit not made at Lessor's request shall be removed by Lessee, at Lessee's
     sole cost and expense, prior to the return of such Unit in accordance with
     Section 3.3.

3.10 ALTERATIONS OR MODIFICATIONS. Lessee shall not make any additions,
     attachments, alterations or improvements to the Equipment without the prior
     written consent of Lessor. At any time during the Original Term of a Lease,
     there may be added to such Lease additional Units of the same type as are
     rented thereunder for a term equal to the remaining portion of such
     Original Term and, subject to the terms and conditions hereof, at the Rent
     applicable to such Units for such term at the time the order for such Units
     is placed, provided that the order is in writing and accepted by Lessor.
     Such acceptance shall be at the sole discretion of Lessor. Each addition,
     attachment, alteration or improvement to any Unit shall belong to and
     become the property of Lessor unless, at the request of Lessor, it is
     removed prior to the return of such Unit by Lessee. Lessee shall be
     responsible for all costs relating to such removal and shall restore such
     Unit to its operating condition that existed at the time it became subject
     to the applicable Lease.

3.11 EQUIPMENT TO BE PERSONAL PROPERTY. Lessee acknowledges and represents that
     the Equipment shall be and remain personal property, notwithstanding the
     manner in which it may be attached or affixed to realty, and Lessee shall
     use reasonable efforts to ensure that the Equipment remains personal
     property.

3.12 FINANCIAL STATEMENTS. Lessee shall promptly furnish to Lessor upon request
     copies of Lessees reports on Form 10-K and 10-Q which are filed with the
     Securities and Exchange Commission and information respecting the
     Equipment, as Lessor may from time to time reasonably request.

3.13 LESSEE REPRESENTATIONS. Lessee hereby represents that, with respect to this
     Agreement and each Lease: (a) the execution, delivery and performance
     thereof by Lessee have been duly authorized by all necessary corporate
     action; (b) the individual executing such document is duly authorized to do
     so; (c) such document constitutes legal, valid and binding obligations of
     Lessee, enforceable in accordance with its terms.


                           IV. DEFAULT AND REMEDIES

4.1  EVENTS OF DEFAULT. The occurrence of any of the following shall constitute
     an Event of Default hereunder: (a) Lessee shall fail to pay any rental or
     other payment due hereunder which failure continues for five (5) days after
     its receipt of notice of nonpayment from Lessor; (b) any representation or
     warranty of Lessee made in this Agreement, any Lease, or in any document
     furnished pursuant to the provisions of this Agreement or otherwise, shall
     prove to have been false or misleading in any material respect as of the
     date when it was made; (c) Lessee shall fail to perform any covenant,
     condition or agreement made by it under any Lease, and such failure shall
     continue for thirty (30) days after its receipt of notice from Lessor; (d)
     bankruptcy, receivership, insolvency, reorganization, dissolution,
     liquidation or other similar proceedings shall be instituted by or against
     Lessee or all or any part of its property under the Federal Bankruptcy Code
     or other law of the United States or of any other competent jurisdiction,
     and, if such proceeding is brought against Lessee, it shall consent thereto
     or shall fail to cause the same to be discharged within sixty (60) days
     after it is filed.

4.2  REMEDIES. If an Event of Default hereunder shall occur and be continuing,
     Lessor may exercise any one or more of the following remedies: (a)
     terminate any or all of the Leases and Lessee's rights thereunder; (b)
     proceed, by appropriate court action or actions, either at law or in
     equity, to enforce performance by Lessee of the applicable covenants of any
     or all of the Leases or to recover damages for the breach thereof; (c)
     recover from Lessee an amount equal to the sum of (i) all amounts due under
     any or all of the Leases on or before the Lessor giving Lessee written
     notice that such Event of Default has occurred and, if Lessor obtains a
     judgment against Lessee with respect to such Event of Default, the entry of
     such judgment, whichever shall last occur, (ii) as liquidated damages for
     loss of a bargain and not as a penalty, the present value of the balance of
     all rentals and other sums payable thereunder and hereunder, without any
     presentment, demand, protest or further notice (all of which are hereby
     expressly waived by Lessee), discounted at a rate of ten percent (10%) per
     annum (the "Discount Rate") as of the date of the payment of such amount,
     and (iii) any loss or damage to the Lessor's residual interest in the
     Equipment caused by such Event of Default; (d) personally, or by its
     agents, take immediate possession of any or all of the Equipment from
     Lessee and, for such purpose, enter upon Lessee's premises where any of the
     Equipment is located with or without notice or process of law and free from
     all claims by Lessee; and (e) require the Lessee to, and the Lessee shall,
     assemble the Equipment and deliver the Equipment to a location which is
     reasonably convenient to Lessor and Lessee. The exercise of any of the
     foregoing remedies by Lessor shall not constitute a termination of any
     Lease or this Agreement unless Lessor so notifies Lessee in writing.

4.3  DISPOSITION OF EQUIPMENT. In the event, upon the occurrence of an Event of
     Default, Lessor repossesses any of the Equipment, Lessor may lease any or
     all of such Equipment, or sell any or all of such Equipment at one or more
     public or private sales, in such manner, at such times and upon such terms
     as Lessor may determine. In the event that Lessor leases any of such Units,
     any rentals received by Lessor for the Remaining Lease Term"(the period
     ending on the date when the Original Term for such Unit would have expired
     if an Event of Default had not occurred), discounted to present value, at
     the Discount Rate, as of the Possession Date (the "Recovery Rentals"), for
     such Units shall be applied to the payment of (a) all costs and expenses
     (including, without limitation, reasonable attorneys' fees) incurred by
     Lessor in retaking possession of, and removing, storing, repairing,
     refurbishing and leasing, such Units, (b) accrued and unpaid rentals as of
     the date Lessor obtained possession of such Units or the date on which
     Lessee made an effective tender of possession of such Units to Lessor,
     whichever shall first occur (the "Possession Date"), (c) the present value
     of the rentals for such Units for the balance of the Original Term of the
     applicable Lease (the "Discounted Remaining Rentals") and any other sums
     payable
     

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     (the "Recovery Proceeds") shall be applied to the payment of the amounts
     referred to in clauses (a) through (d) above and the amount by which the
     Casualty Value for such Units, as of the Possession Date, exceeds the
     Discounted Remaining Rentals (the aggregate of such amounts being referred
     to as the "Sale Recovery Amount"). The balance, if any, of the Recovery
     Rentals, in the case of a release, and of the Recovery Proceeds, in the
     case of a sale or other disposition, shall be applied first to reimburse
     Lessee for any sums previously paid by Lessee as liquidated damages with
     respect to such Units, and any remaining amounts shall be retained by
     Lessor. Lessee shall remain liable to Lessor, with respect to any Units
     which are released or sold or otherwise disposed of, to the extent that the
     Release Recovery Amount exceeds the Recovery Rentals or the Sale Recovery
     Amount exceeds the Recovery Proceeds. Lessor shall be entitled to, and
     Lessee shall have no claim with respect to, all rentals, with respect to
     any period commencing after the expiration of the applicable Remaining
     Lease Term, from released Units.

                               V. MISCELLANEOUS

5.1  PERFORMANCE OF LESSEE'S OBLIGATIONS. Upon Lessee's failure to pay Rent (or
     any other sum due hereunder) or perform any obligation hereunder when due,
     Lessor shall have the right, but shall not be obligated, to pay such sum or
     perform such obligation, whereupon such sum or the cost of such performance
     shall immediately become due and payable hereunder as additional rent, with
     interest thereon at the Default Rate from the date such payment or
     performance was made.

5.2  ASSIGNMENT LESSEE SHALL NOT RELINQUISH POSSESSION OR CONTROL OF, OR ASSIGN,
     SUBLEASE, PLEDGE, HYPOTHECATE OR OTHERWISE TRANSFER, DISPOSE OF OR ENCUMBER
     ANY UNIT, THIS AGREEMENT OR ANY LEASE OR SCHEDULE, OR ANY PART THEREOF OR
     INTEREST THEREIN, OR ANY RIGHT OR OBLIGATION WITH RESPECT THERETO, WITHOUT
     THE PRIOR WRITTEN CONSENT OF LESSOR, except in connection with the
     currently contemplated merger or consolidation of Lessee into a wholly-
     owned subsidiary of Lessee.

5.3  QUIET ENJOYMENT. So long as no Event of Default has occurred and is
     continuing, neither Lessor nor its assignee or any person claming by or
     through Lessor shall interfere with Lessee's right of quiet enjoyment and
     use of the Equipment.

5.4  FURTHER ASSURANCES. Lessee shall, upon the request of Lessor, from time to
     time, execute and deliver such further documents and do such further acts
     as Lessor may reasonably request in order fully to effect the purposes of
     any Lease and Lessor's rights thereunder. Lessor is authorized to file a
     financing statement, signed only by Lessor in accordance with the Uniform
     Commercial Code or signed by Lessor as Lessee's attorney in fact, with
     respect to any of the Equipment.

5.5  RIGHT AND REMEDIES. Each and every right and remedy granted to Lessor under
     any Lease shall be cumulative and in addition to any other right or remedy
     therein specifically granted or now or hereafter existing in equity, at
     law, by virtue of statute or otherwise, and may be exercised by Lessor from
     time to time concurrently or independently and as often and in such order
     as Lessor may deem expedient. Any failure or delay on the part of Lessor in
     exercising any such right or remedy, or abandonment or discontinuance of
     steps to enforce the same, shall not operate as a waiver thereof or affect
     Lessor's right thereafter to exercise the same. Waiver of any right or
     remedy on one occasion shall not be deemed to be a waiver of any other
     right or remedy or of the same right or remedy on any other occasion.

5.6  NOTICES. Any notice, request, demand, consent, approval or other
     communication provided for or permitted hereunder shall be in writing and
     shall be conclusively deemed to have been received by a party hereto on the
     day it is delivered personally to such party at its address set forth above
     (or at such other address as such party shall specify to the other party in
     writing), or if sent by a nationally recognized overnight delivery service,
     the next business day after so sent, or if sent by registered or certified
     mail, return receipt requested, on the fifth day after the day on which it
     is so mailed, addressed to such party at such address.

5.7  SECTION HEADINGS; COUNTERPARTS. Section headings are inserted for
     convenience of reference only and shall not affect any construction or
     interpretation of this Agreement. This Agreement and each Lease may be
     executed in counterparts, and when so executed each counterpart shall be
     deemed to be an original, and such counterparts together shall constitute
     one and the same instrument.

5.8  ENTIRE LEASE. This Agreement and each Lease constitute the entire agreement
     between Lessor and Lessee with respect to the lease of Equipment and
     supersede all other prior or contemporaneous agreements, whether oral or in
     writing, with respect thereto. No waiver or amendment of, or any consent
     with respect to, any provision of this Agreement shall bind either party
     unless set forth in writing, specifying such waiver, consent, or amendment,
     signed by both parties, and then such waiver, consent, or amendment shall
     be effective only in the specific instance and for the specific purpose
     given. Any term or condition of any purchase order or other document (with
     the exception of any Lease) submitted by Lessee in connection with this
     Lease which is in addition to or inconsistent with the terms and conditions
     of this Agreement shall not be binding on Lessor and shall not apply to
     this Agreement. To the extent permitted by applicable law and not otherwise
     specifically provided to Lessee in this Agreement, Lessee hereby waives any
     and all rights or remedies conferred upon a lessee under the California
     Uniform Commercial Code, and any other applicable similar code or statutes
     of another jurisdiction, with respect to a default by Lessor under this
     Agreement.

5.9  SEVERABILITY. Should any provision of this Agreement or any Lease be or
     become invalid, illegal, or unenforceable under applicable law, the other
     provisions of this Agreement and such Lease shall not be affected and shall
     remain in full force and effect, and, to the extent permissible under
     applicable law and possible, any such invalid, illegal or unenforceable
     provision shall be deemed amended to the extent necessary to be valid,
     legal and enforceable and to conform to the intent of the parties;
     provided, however, in the event Lessee's obligation under any Lease to pay
     rent or any other amount shall be invalid, illegal or unenforceable, Lessor
     shall have the right to terminate such Lease as if an Event of Default
     shall have occurred.

5.10 ATTORNEYS' FEES. Should either party institute any action or proceeding to
     enforce this Agreement or any Lease, or any provision hereof or thereof, or
     for a declaration of rights under any such agreement, the prevailing party
     in any such action or proceeding shall be entitled to receive from the
     other party all reasonable out-of-pocket costs and expenses, including,
     without limitation, reasonable attorneys' fees, which it incurs in
     connection with such action or proceeding.

5.11 GOVERNING LAW. This Lease shall be governed in all respects by the laws of
     the State of California with respect to agreements entered into, and to be
     performed, entirely in California. EXCEPT AS OTHERWISE SPECIFICALLY
     PROVIDED IN ANY LEASE, THIS AGREEMENT AND EACH LEASE SHALL BE GOVERNED IN
     ALL RESPECTS BY, AND CONSTRUED IN ACCORDANCE WITH, THE LAWS OF THE STATE OF
     CALIFORNIA. LESSOR AND LESSEE WAIVE ALL RIGHTS TO TRIAL BY JURY IN ANY
     LITIGATION ARISING FROM THIS AGREEMENT OR ANY LEASE. LESSEE CONSENTS TO THE
     NON-EXCLUSIVE JURISDICTION OF THE STATE COURTS OF CALIFORNIA, AND THE
     FEDERAL COURTS SITTING IN THE STATE CALIFORNIA, FOR THE RESOLUTION OF ANY
     DISPUTES HEREUNDER.

5.12 SURVIVAL. All obligations of Lessee to make payments to Lessor under any
     Lease or to indemnify Lessor, pursuant to Section 3.4 or 3.7 above, with
     respect to a Lease, and all rights of Lessor hereunder with respect to a
     Lease, shall survive the termination of such Lease until the expiration of
     any applicable statute of limitations.

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<PAGE>
 
    5.13  PURCHASE OPTION. Notwithstanding anything contained in this Agreement
          or any Lease to the contrary, Lessee shall have the option to purchase
          the Equipment the subject of any Lease, on an "AS IS or WHERE IS"
          basis, at the end of the Original Term of the Lease for a purchase
          price of $1.00. Lessee may exercise such option by giving notice to
          Lessor at least five (5) days prior to the end of the Original Term.

    5.14  EARLY TERMINATION. Lessee shall be entitled, at its option, upon at
          least 30 days prior written notice to Lessor specifying the
          termination date, to terminate any Lease prior to the expiration of
          the Original Term thereof by paying to Lessor an amount equal to the
          Casualty Value as of the termination date for all the Equipment
          subject to each Lease together any accrued and unpaid Rent as of the
          termination date.

LESSEE, BY THE SIGNATURE BELOW OF ITS AUTHORIZED REPRESENTATIVE, ACKNOWLEDGES
THAT IT HAS READ THIS LEASE, UNDERSTANDS IT, AND AGREES TO BE BOUND BY ITS TERMS
AND CONDITIONS.



CISCO SYSTEMS CAPITAL CORPORATION. (LESSOR)      PSINET INC. (LESSEE)

By: /s/ Brian P. Fukuhara                        By: /s/ Edward D. Postal
  ----------------------------------------         ----------------------------
        (Authorized Signature)                         (Authorized Signature)

    Manager Worldwide Financial Services             Senior Vice President & CFO
------------------------------------------       -------------------------------
             (Name/Title)                                   (Name/Title)

    November 4, 1997                                 October 24, 1997
------------------------------------------       -------------------------------
               (Date)                                         (Date)
                                               
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