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                                                                    Exhibit 10.3




               AMENDED AND RESTATED PLEDGE AND SECURITY AGREEMENT

         THIS AMENDED AND RESTATED PLEDGE AND SECURITY AGREEMENT, dated as of
October 31, 1997 (this "Agreement"), is made by FORE SYSTEMS HOLDINGS
CORPORATION, a Delaware corporation (the "Pledgor"), FORE Systems, Inc., a
Delaware corporation ("FORE"), MELLON BANK, N.A. (the "Tranche A Lender",
together with its successors and assigns from time to time, in its capacity as
secured party hereunder (the "Pledgee"), MELLON FINANCIAL SERVICES CORPORATION
#4 and MELLON BANK, N.A., as custodian (in such capacity, the "Custodian").
Capitalized terms used but not otherwise defined in this Agreement have the
respective meanings specified in (i) Appendix 1 to that certain Participation
Agreement, dated as of December 13, 1995 (as amended, supplemented or otherwise
modified from time to time, the "Participation Agreement"), among FORE Systems,
Inc., Brush Creek Business Trust, a statutory Delaware business trust (the
"Trust") acting through Wilmington Trust Company, not in its individual
capacity except as expressly stated therein, but solely as Certificate Trustee,
Mellon Financial Services Corporation #4 and Mellon Bank, N.A.; and the rules
of interpretation stated in such Appendix 1 shall be applicable to this
Agreement and (ii) in the First Amendment to such Participation Agreement dated
as of October 31, 1997.

                             PRELIMINARY STATEMENTS

                                  (1)    The Tranche A Lender has entered
                                         into the Amended and Restated Term
                                         Loan Agreement, pursuant to which the
                                         Tranche A Lender has agreed to make
                                         the Tranche A Loan to the Trust, to be
                                         evidenced by the Tranche A Note, to
                                         provide the funds necessary to
                                         refinance a portion of the Note issued
                                         to Mellon Bank N.A. under the
                                         Construction Loan Agreement.

                                  (2)    Pledgor will deliver, or cause to be
                                         delivered from time to time, to the
                                         Custodian in accordance with the terms
                                         hereof and of that certain agreement
                                         between the Pledgor and the Custodian
                                         (the "Custody Agreement"), Pledged
                                         Property with a Collateral Value in an
                                         amount not less than the Collateral
                                         Requirement and at all


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                                         times until all obligations of the
                                         Guarantor and the Borrower created
                                         under the Refinancing Loan Documents,
                                         with respect to the Tranche A Loan,
                                         have been fully satisfied or discharged
                                         in accordance with the terms thereof,
                                         to maintain, or cause to be maintained
                                         from time to time, Pledged Property
                                         with the Custodian in an amount not
                                         less than the Collateral Requirement
                                         from time to time thereafter, for the
                                         purpose of securing all obligations of
                                         Pledgor, with respect to the Tranche A
                                         Loan, under the Guaranty Agreement, as
                                         amended, (whether for principal,
                                         interest or other amounts due and
                                         payable thereunder); provided, however,
                                         the maximum liability of the Pledgor
                                         hereunder and under the Guaranty
                                         Agreement (and of FORE under the
                                         Guaranty) is limited to Pledged
                                         Property required hereby to be pledged
                                         and the "Pledged Property" required to
                                         be pledged under the Pledge and
                                         Security Agreement-B (Refinancing),
                                         however such obligations are created,
                                         arising or evidenced, whether direct or
                                         indirect, joint or several, absolute or
                                         contingent, or now or hereafter
                                         existing, or due or to become due
                                         (including all amounts which would
                                         become due but for the operation of the
                                         automatic stay under Section 362(a) of
                                         the United States Bankruptcy Code, and
                                         the operation of Sections 502(b) and
                                         506(b) of the United States Bankruptcy
                                         Code) (all of the foregoing,
                                         collectively, the "Secured
                                         Obligations").

                                  (3)    Pledgor acknowledges and agrees that it
                                         will derive substantial benefits from
                                         the execution and delivery of this
                                         Agreement, and each of the Refinancing
                                         Loan Documents to which it is a party,
                                         and the transactions contemplated
                                         thereunder.

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         NOW, THEREFORE, for good and valuable consideration, the receipt of
which is hereby acknowledged, the Pledgor, the Custodian and the Pledgee,
intending to be legally bound, hereby agree as follows:

SECTION 1. Pledge and Assignment. As collateral security for the due and
punctual payment of all of the Secured Obligations, the Pledgor hereby pledges,
assigns, conveys, transfers, delivers and grants to the Pledgee a security
interest in and continuing lien on all of the following property, whether now
owned or existing or hereafter acquired or arising, and wherever located
(collectively, the "Collateral"), subject to the terms and conditions contained
herein:

         (a)      the Collateral Account (as hereinafter defined) and all
                  moneys, funds, instruments, and securities, including,
                  Pledged Property, now in or from time to time credited to or
                  on deposit in the Collateral Account, including, all Pledged
                  Property deposited in the Collateral Account pursuant to
                  Sections 3 and 4(a) hereof;

         (b)      all interest, profit (whether of cash or securities) and
                  distributions of any of the foregoing; and

         (c)      all proceeds (as defined in the Uniform Commercial Code) of
                  the foregoing.

                  Notwithstanding anything to the contrary contained herein or
in any other Refinancing Loan Document or in any Operative Document, Mellon
Bank N.A. (in its capacity as Pledgee under this Agreement) shall only have
rights in and to the Pledged Property until the repayment in full of the
Secured Obligations.

      SECTION 2. Collateral Account; Transfer of Collateral; Definitions.
(a)Concurrently herewith the Pledgor has established at the branch of the
Custodian located at Mellon Bank, N.A., One Mellon Bank Center, Pittsburgh,
Pennsylvania 15259, a collateral account designated on the records of the
Custodian as "FORE Systems Holding Corp. Collateral Account, Mellon Bank, N.A.,
as Secured Party", account number 856-33508-9 (herein, together with any
substitution therefor, the "Collateral Account"). The Collateral Account shall
be segregated from any and all other accounts or other property of the Pledgor,
and subject to Section 4 hereof (with respect to permitted withdrawals) and
Section 7 hereof (with respect to investment at the direction of Pledgor), the
Pledgee shall have


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sole dominion and control over the Collateral Account. Without limiting the
generality of the foregoing, so long as an Event of Default (as hereinafter
defined) has occurred and is continuing the Pledgee shall have the sole right
to make withdrawals from the Collateral Account. Except as expressly provided
in Section 4, until the Secured Obligations are paid in full, the Pledgor shall
have no right to make withdrawals from the Collateral Account or to otherwise
exercise any control with respect to any securities or other property from time
to time on deposit in or credited to the Collateral Account, or provide
substitute Collateral.

         (b) Intentionally Omitted.

         (c) The Pledgor shall deliver with any securities transferred
hereunder all appropriate undated bond powers, duly executed in blank and any
and all other forms related to transfer requested by the Custodian, completed
or executed so to make such transfer valid under applicable law and the rules
of any securities exchange or otherwise.

         (d) The Pledgor and the Pledgee agree to do or take all actions (or
omit from taking actions) in order to make all transfers contemplated hereby
valid under applicable law and the rules of any securities exchange or
otherwise.

         (e) (i) For the purpose of this Agreement, "Pledged Property" shall
mean Marketable Collateral and any undistributed Earnings thereon, delivered
and duly pledged in accordance with Section 1 and maintained in accordance with
Section 3.

             (ii) For the purpose of this Agreement, the "Collateral
Requirement" shall be an amount equal to the sum of the aggregate principal
amount outstanding from time to time under the Tranche A Notes plus all accrued
but unpaid interest on the entire outstanding principal amount thereof.

             (iii) For the purposes of establishing the Collateral Value of
Pledged Property held in accordance with Sections 1, 3 and 4a in the Collateral
Account, the term "Fair Market Value" shall mean, in the case of cash, the
amount of such cash, and otherwise, the market value of the applicable Pledged
Property as determined by reference to market quotes provided on the date of
valuation by Bloomberg Financial Market Service, or if such rate is
unavailable, by Interactive Data Services Inc., Telerate, Reuters and/or any
major daily financial publication such as the Wall Street Journal or The New
York Times.

             (iv) For the purpose of this Agreement "Collateral Value" shall
mean (i) in the case of cash, 100% of the amount of such cash, (ii) in the case
of a certificate of deposit issued

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by Mellon Bank, 100% of the Fair Market Value, (iii) in the case of Pledged
Property, other than cash or a certificate of deposit issued by Mellon Bank
N.A., 90% of the Fair Market Value of the Pledged Property properly delivered
and perfected hereunder.

         SECTION 3. Maintaining Pledged Property; Additional Deposits to
Collateral Account. Subject to Section 4, the Pledgor shall maintain at all
times until the Secured Obligations have been fully satisfied and discharged in
accordance with the Refinancing Loan Documents Pledged Property having a
Collateral Value equal to the Collateral Requirement. All such Pledged Property
shall be unrestricted and shall not be subject to any Lien, except for the
Liens created by the Refinancing Loan Documents.

         SECTION 4. Valuation; Required Collateral Level; Substitutions and
Release. (a) On the first Business Day of each calendar month during the
Collateral Term, the Custodian shall determine the aggregate Collateral Value
of the Pledged Property in the Collateral Account. Such determination shall be
promptly furnished, in writing, to the Pledgor and the Pledgee. To the extent
the Collateral Value of the Pledged Property in the Collateral Account is less
than, at any time prior to the full satisfaction and discharge of the Secured
Obligations in accordance with the terms of the Refinancing Loan Documents, the
Collateral Requirement, the Pledgor promptly, but in any event within seven
days after receipt of notice of such determination, shall transfer Pledged
Property to such account in an amount equal to or exceeding the Collateral
Value shortfall amount so that the Collateral Requirement is maintained at all
times prior to the full satisfaction and discharge of the Secured Obligations
in accordance with the terms of the Refinancing Loan Documents. To the extent
the Collateral Value of the Pledged Property in the Collateral Account exceeds
the Collateral Requirement on the first Business Day of any calendar month
prior to the full satisfaction and discharge of the Secured Obligations in
accordance with the terms of the Refinancing Loan Documents and no Event of
Default (as hereinafter defined) or Default shall have occurred and be
continuing, the Pledgor may request the Pledgee, with a copy to the Custodian,
to release such excess Collateral to the Pledgor or upon its order or the order
of its designee, and the Pledgee shall release and direct the Custodian to
release such excess Collateral to the Pledgor or upon its order in accordance
with the release procedures set forth in Section 4(b) below.

         (b) During such time as Pledged Property is held in the Collateral
Account, upon delivery of prior notice to the Custodian, the Pledgor may, at
any time and so long as no Event of Default shall have occurred and be
continuing, substitute for any Collateral subject to this Agreement, other
Pledged Property


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having in the aggregate at least equivalent Collateral Value, and such
substitute Pledged Property shall be Collateral for all purposes hereunder. All
such substitute Pledged Property shall be deposited in and credited to the
Collateral Account, and shall be accompanied by proper instruments of
assignment and/or bond powers executed in blank or to the Pledgee by the
Pledgor in accordance with the instructions of the Pledgee. Collateral for
which the Custodian has received substituted Collateral to the extent permitted
hereunder or Collateral which is otherwise to be released in accordance with
4(a) above shall be promptly released by the Pledgee and shall be redelivered
and retransferred to the Pledgor or transferred to such Pledgor's account by
the Custodian upon the instructions of the Pledgor and shall be accompanied by
proper instruments of reassignment and/or bond powers (as appropriate) executed
by the Custodian (or its nominee) or the Pledgee, as applicable, as the Pledgor
shall direct, all at the expense of the Pledgor and without recourse,
representation or warranty by the Pledgee or the Custodian or any of their
nominees (except for the representation that the released Collateral is free
and clear of all Liens created by, through or under the Pledgee or the
Custodian).

         (c) The delivery of a written notice pursuant to clause (a) above by
the Pledgor to the Custodian, prior to effecting any sale, substitution, or
additional pledge of Collateral as contemplated by this Section 4(c) shall
constitute a representation and warranty by the Pledgor that, to Pledgor's
knowledge, no violation of the rules and regulations of the Federal Reserve
Board exists with respect to the Tranche A Loan and such sale, substitution or
pledge of Collateral will not result in a violation of any rule or regulation
of the Federal Reserve Board.

         SECTION 5. The Custodian. (a) The Pledgee hereby appoints the
Custodian as the Pledgee's agent (i) for retaining physical possession of any
cash included in the Collateral and any physical certificates or instruments or
other physical representation or evidence of any Collateral in accordance with
the provisions of this Agreement and (ii) for holding the interest of the
Pledgee in all book-entry securities in accordance with the provisions of this
Agreement.  All Collateral shall be in the Collateral Account and segregated
from all other property, including, without limitation, that of the Pledgor and
the Pledgee.  The Custodian hereby accepts such appointment.

         (b) The Custodian shall retain physical possession of the certificates
or instruments representing or evidencing the Collateral if the Collateral is
issued in physical form; provided that the Custodian may have such Collateral
credited to the Custodian's account at The Depository Trust Company ("DTC"). If
the Collateral is in book-entry form, the Collateral shall be (i)


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credited to the Custodian or its nominee in the Custodian's account at DTC or
(ii) registered on the books of the issuer thereof in the name of the
Custodian.  The Custodian shall mark its books and records with respect to the
Collateral to indicate security interests of the Pledgee in the Collateral.
Certificated securities may be held (in the discretion of the Pledgee) in the
name of the Pledgor, endorsed or assigned in blank, or endorsed or assigned to
the Pledgee, the Custodian or DTC (or its nominee).

         (c) All book-entry obligations of the United States Government issued
in the form of an entry on the records of the Federal Reserve Bank of New York
shall be (1) identified on the records of the Federal Reserve Bank of New York
for the account of Mellon Bank, N.A. or its agent and (2) identified on the
records of Mellon Bank, N.A. as part of the Collateral Account. The Custodian
shall mark its books and records with respect to the Collateral to indicate the
security interests of the Pledgee in the Collateral.

         (d) In addition, subject to Section 7 hereof, the Custodian shall at
all times have the right to exchange certificates or instruments representing
or evidencing Pledged Property for certificates or instruments for Pledged
Property of smaller or larger denominations for any purpose consistent with its
performance of this Agreement; provided that the aggregate principal amount of
the certificates or instruments received upon such an exchange shall not be
less than the aggregate principal amount of the certificates or instruments
tendered for exchange.

         (e) The Custodian acknowledges receipt of this Agreement, certifies
that no notice of any other security agreement or claim affecting the
Collateral has been received by it, states that the Collateral will be held in
the Collateral Account for the benefit of the Pledgee and agrees to hold the
Collateral solely for the benefit of the Pledgee and subject to the control of
the Pledgee, as provided in this Agreement. The Custodian agrees to exercise
the same degree of care as exercised by banks generally for similar property in
exercising its duties under this Agreement. The duties of the Custodian under
this Agreement shall only be those set forth in this Agreement.

         SECTION 6. Interest, Distributions, etc. on Collateral. If, while this
Agreement is in effect, the Pledgor shall become entitled to receive or shall
receive any interest or other cash payments or property paid in respect of the
Pledged Property (to the extent such property or other proceeds, profits, or
other property is cash or is reduced to cash, the "Earnings") whether as an
addition to, in substitution of, or in exchange for any security included in
the Pledged Property, or otherwise, subject to Sections 4(a) and 4(b), the
Pledgor agrees to accept the same


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as the Pledgee's agent and to hold the same in trust on behalf of and for the
benefit of Pledgee and to convert the same to Pledged Property, as necessary,
and to deliver the same forthwith to the Custodian with the endorsement of the
Pledgor when necessary and/or appropriate undated bond powers, duly executed in
blank, or to the Pledgee, as the Pledgee may direct, to be deposited in the
Collateral Account.

         SECTION 7. Investment of Collateral. (a) The Custodian shall invest
all moneys on deposit from time to time (including moneys on deposit upon the
sale or maturity of securities) in the Collateral Account so long as no Event
of Default or Default shall have occurred and be continuing, at the direction
of the Pledgor, in Pledged Property having an equal or greater Collateral Value
than the sold or matured security. Such investments, together with any interest
or other earnings resulting from such investments, shall be maintained in the
Collateral Account and shall be reinvested as provided in this paragraph. The
Custodian shall collect so much of the moneys payable on account of interest as
it is able to collect in the ordinary course and shall hold such interest in
the Collateral Account, provided that in no event shall the provisions hereof
impose on the Custodian the obligation to institute any collection proceedings,
judicial or otherwise, in respect of investments comprising the Collateral.
Neither the Custodian nor the Pledgee shall be liable or responsible for any
loss resulting from any such investments, except for any such loss resulting
from the gross negligence or willful misconduct of such person.

         SECTION 8. Rights of the Custodian. Neither the Custodian nor the
Pledgee shall be liable for failure to collect or realize upon the Collateral,
or any part thereof, or for any delay in so doing nor shall any of them be
under any obligation to take any action whatsoever with regard thereto, except
for any such persons failure resulting from the gross negligence or wilfull
misconduct of such person. Any or all of the Collateral may, if an Event of
Default has occurred and is continuing, without notice, be registered in the
name of the Custodian or its nominee or the Pledgee or its nominee, if not then
so registered, and the Custodian or its nominee or the Pledgee or its nominee
may thereafter without notice, exercise all rights, privileges or options
pertaining to any of the securities included in the Collateral, if appropriate,
as if it were the absolute owner thereof, all without liability except to
account for property actually received by it, and the Pledgor shall execute and
deliver (or cause to be executed and delivered) to the Custodian all powers of
attorney, interest coupons and other instruments for the purpose of enabling
the Custodian to exercise the rights and powers which the Custodian is entitled
to exercise pursuant to this Section.

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      SECTION 9. Application of Collateral by Custodian Prior to an Event of
Default. At the Maturity Date if the Lessee shall have elected to purchase the
Property pursuant to the Lease, so long as no Event of Default or Default shall
have occurred and be continuing the Custodian shall, upon 10 days written
notice from the Lessee and the Pledgor, liquidate the Pledged Property in the
Collateral Account and apply the proceeds to any purchase of the Property
pursuant to the Lease; provided, however, that the Custodian shall transfer the
proceeds of such Pledged Property only upon receipt of a certification of
Lessor stating that the Lessor has received or has made arrangements
satisfactory to it to receive in connection with any such purchase an amount
which, together with the proceeds of the Pledged Property, will be sufficient
to pay the Lease Balance.

      SECTION 10. Events of Default. Each of the following events shall
constitute an event of default under this Agreement (each, an "Event of
Default"):

            (a) The failure of Pledgor to pay, after three days prior written
       notice by means of invoice, the reasonable fees and expenses of the
       Custodian;

            (b) The failure of Pledgor to comply with any of the terms or
       provisions of this Agreement, which (except as provided in (a) above)
       failure shall have continued for a period of five (5) days after written
       notice to FORE or Pledgor; or

            (c) A Lease Event of Default, or Refinancing Loan Agreement Event
       of Default shall occur and be continuing.

       SECTION 11. Remedies upon Default. If an Event of Default shall have
occurred and be continuing, then the Pledgee shall have all the rights and
remedies of a secured party under the Uniform Commercial Code in effect in (the
"UCC") and other applicable law, and, in addition, the Pledgee, upon written
notice to FORE, may direct the Custodian from time to time to:

            (a) deliver and pay over all or any portion of the Collateral in
       the Collateral Account to the Pledgee, to be applied to satisfy accrued
       and unpaid Secured Obligations;

            (b) sell the Collateral, or any part thereof, at any public or
       private sale or on any securities exchange, for cash, upon credit or for
       future delivery, as the Pledgee shall deem appropriate. The Pledgee
       shall be authorized at any such sale to restrict the prospective bidders
       or purchasers to persons who will represent and agree that they are
       purchasing the Collateral for their own account for investment and not
       with a view to the distribution or sale


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       thereof, and upon consummation of any such sale, the Pledgee shall have
       the right to assign and transfer and have the Custodian transfer and
       deliver to the purchaser or purchasers thereof the Collateral so sold.
       Each such purchaser at any such sale shall hold the property sold
       absolutely free from any claim or right on the part of the Pledgor and
       FORE, and each of the Pledgor and FORE hereby waives (to the extent
       permitted by law) all rights of redemption, stay and/or appraisal which
       it now has or may at any time in the future have under any rule or law
       or statute now existing or hereafter enacted. The Pledgee shall give the
       Pledgor at least ten (10) days' written notice of the Pledgee's
       intention to make any such public or private sale or sales at any
       broker's board or on any such securities exchange. Such notice, in case
       of public sale, shall state the time and place fixed for such sale. Any
       such public sale shall be held at such time or times within ordinary
       business hours and at such place or places, as the Pledgee may fix in
       the notice of such sale.  At any such sale, the Collateral, or portion
       thereof, to be sold may be sold in one sale as an entirety or in
       separate sales, as the Pledgee may (in its sole and absolute discretion)
       determine and the Pledgee may bid (which bid may be in whole or in part,
       in the form of cancellation of indebtedness) for and purchase for the
       account of the Pledgee the whole or any part of the Collateral. The
       Pledgee shall not be obligated to make any sale of Collateral if it
       shall determine not to do so, regardless of the fact that notice of sale
       of Collateral may have been given. The Pledgee may, without notice or
       publication, adjourn any public or private sale or cause the same to be
       adjourned from time to time by announcement at the time and place fixed
       for sale, and such sale may, without further notice, be made at the time
       and place to which the same was so adjourned.  In case a sale of all or
       any part of the Collateral is made on credit or for future delivery, the
       Collateral so sold may be retained by the Pledgee until the sale price
       is paid by the purchaser or purchasers thereof, but the Pledgee shall
       not incur any liability in case any such purchaser or purchasers shall
       fail to take up and pay for the Collateral so sold and, in case of any
       such failure, such Collateral may be sold again upon like notice; or

            (c) proceed by a suit or suits at law or in equity to foreclose the
       security interest granted under this Agreement and to sell the
       Collateral, or any portion thereof, pursuant to a judgment or decree of
       a court or courts of competent jurisdiction.

       In addition, the Pledgee shall have all of the rights granted to the
Pledgee under this Agreement upon the occurrence


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of an Event of Default.

         FORE (but not the Pledgor) shall be liable for the deficiency if the
proceeds of any sale or other disposition of the Collateral are insufficient to
pay all amounts to which the Pledgee is entitled, and the fees and
disbursements of any attorneys employed by the Pledgee to collect such
deficiency.

         SECTION 12. Application of Proceeds of a Sale. The cash or proceeds of
sale of Collateral sold pursuant to Section 11 of this Agreement shall be paid
to the Pledgee until the Secured Obligations are paid in full; thereafter all
such proceeds shall be delivered to the Pledgor.

         SECTION 13. Conditions of Effectiveness. This Agreement shall become
effective when the Pledgee shall have received a counterpart of this Agreement
duly executed and delivered by Pledgor.

         SECTION 14. Disposition, etc. Without the prior written consent of the
Pledgee, the Pledgor agrees not to sell, assign, transfer, exchange, or
otherwise dispose of, or grant any option with respect to, the Pledged Property
held in the Collateral Account, except as provided in Section 4, and Sections
11 and 12, of this Agreement, nor will it create, incur or permit to exist any
Lien with respect to any of the Pledged Property held in the Collateral
Account, or any interest therein, or any proceeds thereof, except for the lien
and security interest provided for by this Agreement.

         SECTION 15. Exoneration; Indemnity. Neither the Custodian, the
Pledgee, nor any director, officer or employee of the Custodian or the Pledgee,
shall be liable to the Pledgor or FORE for any action taken or omitted to be
taken by them or any one of them, pursuant to this Agreement, except to the
extent arising from its or their own gross negligence or willful misconduct;
nor shall the Custodian or the Pledgee be responsible for the validity,
effectiveness or sufficiency hereof or of any document or security furnished
pursuant hereto or in connection herewith. The Custodian and the Pledgee shall
be entitled to rely on any communication, instrument or document believed by
them to be genuine and correct and to have been signed or sent by the proper
person or persons. FORE agrees to indemnify and hold harmless the Custodian and
the Pledgee, and/or the directors, officers, employees, agents or nominees of
the Custodian or the Pledgee, from and against any and all liability incurred
by the Custodian or the Pledgee (or such agent or nominee) hereunder or in
connection herewith, except to the extent such liability shall be due to
willful misconduct or gross negligence on the part of the Custodian or the
Pledgee or such directors, officers, employees, agents or nominees. In
furtherance hereof, each of the Pledgor


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and FORE acknowledges and agrees that the Custodian and the Pledgee may act on
the instructions of the Pledgor acting alone with respect to all matters
related hereto, including the receipt, release, transfer, substitution or
investment of any Collateral or the transfer of any amounts pursuant hereto.
Any liability of the Custodian and the Pledgee under this Agreement shall be
several and not joint.

         SECTION 16. The Pledgee Appointed Attorney-in-Fact. The Pledgor hereby
appoints the Pledgee and the Custodian, acting either individually or jointly,
as the Pledgor's attorney-in-fact for the purpose of carrying out the
provisions of this Agreement and taking any action and executing any instrument
which they may deem necessary or advisable to accomplish the purposes hereof,
which appointment is irrevocable and coupled with an interest. Without limiting
the generality of the foregoing, both the Pledgee and the Custodian, acting
either individually or jointly, shall have the right and power to receive,
endorse and correct all checks, drafts and other orders for the payment of
money made payable to the Pledgor representing any interest payment or other
distribution payable or distributable in respect of the Collateral or any part
thereof and to give full discharge for the same.

         SECTION 17. Change of Custodian. No change in Custodian may occur
without the express written consent of the Pledgee and the Pledgor. The
Custodian may resign by giving thirty (30) days' notice to the parties to this
Agreement. The Pledgee may then appoint a successor Custodian with the prior
written consent of the Pledgor, which shall not be unreasonably withheld or
delayed, whereupon the successor Custodian shall succeed to the rights, powers
and duties of the Custodian.

         SECTION 18. No Waiver; Cumulative Remedies. No failure on the part of
Custodian or the Pledgee to exercise, and no delay in exercising, any right,
power or remedy hereunder shall operate as a waiver thereof, nor shall any
single or partial exercise of any such right, power or remedy by the Custodian
or the Pledgee preclude any other further exercise thereof or the exercise of
any other right, power or remedy. All remedies hereunder are cumulative and are
not exclusive of any other remedies provided by law or in equity.

         SECTION 19. Termination. This Agreement shall terminate on the payment
in full of the Secured Obligations and the payment of all other amounts owing
to the Tranche A Lender under the Refinancing Loan Documents, at which time the
Pledgee shall execute and deliver to the Pledgor an appropriate release and
shall reassign, retransfer and redeliver (or cause to be reassigned,
retransferred and redelivered) to the Pledgor, or to such person or persons as
the Pledgor shall designate, against

                                      -12-


<PAGE>   13


receipt, such of the Collateral pledged by the Pledgor as shall have not been
sold or otherwise applied pursuant to the terms hereof and shall still be held
by the Custodian pursuant to this Agreement, together with proper instruments
of reassignment and retransfer. Any such reassignment and retransfer shall be
without recourse, representation or warranty by the Pledgee or the Custodian
and shall be at the expense of the Pledgor (except for the representation that
the released Pledged Property is free and clear of all Liens created by,
through or under the Pledgee or the Custodian).

         SECTION 20. Notices. All communications and notices hereunder shall be
in writing, unless otherwise specifically provided herein, and delivered or
mailed by first-class mail, postage prepaid, registered or certified, return
receipt requested, by overnight courier, or by facsimile transmission, to the
address of the Pledgor (which shall be the same address as the address of FORE)
and Pledgee set forth in the Participation Agreement, or, as to each party, at
such other address as shall be designated by such party in a written notice to
the other parties hereto complying as to delivery with the terms of this
Section. All notices, requests, demands and other communications provided for
hereunder shall be effective upon deposit in the United States mail or upon
facsimile transmission during business hours.

         SECTION 21. Further Assurances; etc. Each of the Pledgor, Pledgee and
Custodian agrees to do such further acts and things, and to execute and deliver
such additional conveyances, assignments, agreements and instruments, including
the filing of any financing or continuation statements under the Uniform
Commercial Code in effect in any jurisdiction with respect to the security
interests created hereby as may be reasonably required to effect the terms and
provisions of this Agreement. The Pledgor also hereby irrevocably authorizes
the Pledgee to file any such financing or continuation statement, without the
signature of the Pledgor to the extent permitted by applicable law, as the
Pledgee may at any time reasonably request in connection with the
administration or enforcement of this Agreement in order better to assure and
confirm unto the Pledgee its rights, powers and remedies hereunder. The Pledgor
hereby consents and agrees that the issuers of or obligors in respect of the
Collateral or any registrar or transfer agent or trustees for any of the
Collateral shall be entitled to accept the provisions hereof as conclusive
evidence of the right of the Pledgee to effect any transfer pursuant to this
Agreement, notwithstanding any other notice or direction to the contrary
heretofore or hereafter given by the Pledgor or any other person to any of such
issuers or obligors or to any such registrar or transfer agent or trustees. The
Pledgor further covenants that it will defend the Pledgee's right, title and
interest in the Collateral, from time


                                      -13-

<PAGE>   14



to time pledged by the Pledgor, against the claims and demands of all
Persons.

         SECTION 22. Assignment. This Agreement, and the terms, covenants and
conditions hereof, shall be binding upon and inure to the benefit of the
parties hereto and their respective successors and assigns, except that neither
Pledgor nor Pledgee shall be permitted to assign this Agreement except in
connection with an assignment permitted under the Participation Agreement.

         SECTION 23. Amendments. Neither this Agreement nor any provisions
hereof may be amended, modified, waived or terminated, except by an instrument
in writing signed by a duly authorized officer of the Pledgee and the Pledgor.

         SECTION 24. Governing Law. This Agreement shall be governed by and
construed in accordance with the laws of the Commonwealth of Pennsylvania,
without regard to conflicts of law principles.

         SECTION 25. Costs, Expenses and Taxes. FORE agrees to pay on demand
all reasonable costs and expenses of, and all stamp and other taxes payable
(including any penalties) incurred by the Custodian or the Pledgee in
connection with the preparation, execution, delivery, administration and
enforcement of this Agreement.

         SECTION 26. Fees and Expenses of Custodian. The fees and expenses of
the Custodian shall be payable by FORE as set forth in a separate agreement
between the Custodian and FORE, which fees shall be those fees customarily
charged by custodians performing the foregoing services.

         SECTION 27. Headings. The headings in this Agreement are for
convenience only and shall not be deemed or construed to affect the meaning or
construction of any of the provisions of this Agreement.

         SECTION 28. Counterparts. This Agreement may be executed in any number
of counterparts, each of which, when executed and delivered, shall be deemed to
be an original and all of which taken together shall constitute one and the
same instrument.

         SECTION 29. SUBMISSION OF JURISDICTION. TO THE FULLEST EXTENT
PERMITTED BY LAW, THE PLEDGOR, PLEDGEE AND CUSTODIAN HEREBY SUBMIT TO THE
EXCLUSIVE JURISDICTION OF THE UNITED STATES DISTRICT COURT FOR THE WESTERN
DISTRICT OF PENNSYLVANIA AND ANY COURT OF THE COMMONWEALTH OF PENNSYLVANIA FOR
PURPOSES OF ALL LEGAL PROCEEDINGS ARISING OUT OF OR IN CONNECTION WITH THIS
AGREEMENT AND THE TRANSACTIONS CONTEMPLATED HEREBY. THE PLEDGOR, PLEDGEE AND
CUSTODIAN IRREVOCABLY WAIVE, TO THE FULLEST EXTENT PERMITTED BY LAW, ANY
OBLIGATION WHICH SUCH PARTY MAY NOW OR HEREAFTER HAVE TO THE LAYING OF THE VENUE
OF ANY SUCH PROCEEDINGS BROUGHT IN SUCH A COURT AND ANY CLAIM THAT ANY SUCH
PROCEEDING BROUGHT IN SUCH A COURT HAS BEEN BROUGHT IN AN INCONVENIENT FORUM.


                                      -14-

<PAGE>   15



         IN WITNESS WHEREOF, the parties hereto have caused this AMENDED AND
RESTATED PLEDGE AND SECURITY AGREEMENT to be duly executed by their duly
authorized officers on the dates specified below with effect from the date
first above written.

                                   FORE SYSTEMS HOLDING CORPORATION as Pledgor
Attest:

/s/ CHRISTOPHER H. GEBHARDT        By:     /s/ THOMAS J. GILL
----------------------------            -----------------------------
                                        Name:  Thomas J. Gill 
                                        Title: Treasurer


                                   FORE SYSTEMS, INC.
Attest:

/s/ CHRISTOPHER H. GEBHARDT        By:     /s/ THOMAS J. GILL
----------------------------            -----------------------------
                                        Name:  Thomas J. Gill 
                                        Title: Chief Operating Officer


                                   MELLON BANK, N.A.,
                                   as Pledgee
Attest:

/s/ FRANK LABARBERA                By:     /s/ BRIAN CIAVERELLA
----------------------------            -----------------------------
                                        Name:  Brian Ciaverella 
                                        Title: Vice President

                                   MELLON BANK, N.A.,
                                   as Custodian
Attest:

/s/ JEFFREY T. RECKER              By:    /s/ CHRISTINA HITCHINS
----------------------------            -----------------------------
                                        Name:  Christina Hitchins 
                                        Title: Officer


                                      -15-


<PAGE>   16





                                   MELLON FINANCIAL SERVICES CORPORATION #4

Attest:

/s/ MICHAEL J. TIESI               By:     /s/ STEPHEN R. VIEHE
----------------------------            -----------------------------
                                        Name:  Stephen R. Viehe 
                                        Title: Vice President



<PAGE>   17

                               TABLE OF CONTENTS
<TABLE>
<CAPTION>
                                                                            Page
                                                                            ----
<S>         <C>                                                            <C>

SECTION 1.  Pledge and Assignment............................................-2-

SECTION 2.  Collateral Account; Transfer of Collateral; Definitions..........-3-

SECTION 3.  Maintaining Pledged Property; Additional 
            Deposits to Collateral Account...................................-4-

SECTION 4.  Valuation; Required Collateral Level; Substitutions and
            Release..........................................................-4-

SECTION 5.  The Custodian....................................................-5-

SECTION 6.  Interest, Distributions, etc. on Collateral......................-7-

SECTION 7.  Investment of Collateral.........................................-7-

SECTION 8.  Rights of the Custodian..........................................-7-

SECTION 9.  Application of Collateral by Custodian Prior to an Event of
            Default..........................................................-8-

SECTION 10. Events of Default................................................-8-

SECTION 11. Remedies upon Default............................................-8-

SECTION 12. Application of Proceeds of a Sale...............................-10-

SECTION 13. Conditions of Effectiveness.....................................-10-

SECTION 14. Disposition, etc................................................-10-

SECTION 15. Exoneration; Indemnity..........................................-10-

SECTION 16. The Pledgee Appointed Attorney-in-Fact..........................-11-

SECTION 17. Change of Custodian.............................................-11-

SECTION 18. No Waiver; Cumulative Remedies..................................-11-

SECTION 19. Termination.....................................................-11-

SECTION 20. Notices.........................................................-12-
</TABLE>

                                       i



<PAGE>   18

<TABLE>
<CAPTION>
                                                                            Page
                                                                            ----
<S>         <C>                                                            <C>
SECTION 21. Further Assurances; etc.........................................-12-

SECTION 22. Assignment......................................................-13-

SECTION 23. Amendments......................................................-13-

SECTION 24. Governing Law...................................................-13-

SECTION 25. Costs, Expenses and Taxes.......................................-13-

SECTION 26. Fees and Expenses of Custodian..................................-13-

SECTION 27. Headings........................................................-13-

SECTION 28. Counterparts....................................................-13-
</TABLE>

                                       ii