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                                 EXHIBIT 10.24

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                           NON-COMPETITION AGREEMENT


          THIS AGREEMENT made the 14th day of October, 1987

     BETWEEN

               TERENCE H. MATTHEWS,
               of the City of Kanata,
               in the Province of Ontario

               (hereinafter called the "Matthews")

     AND

               NEWBRIDGE NETWORKS CORPORATION,
               a corporation incorporated pursuant to the Canada
               Business Corporations Act having its registered
               office at 1501 Baxter Road, Ottawa, Ontario

               (hereinafter called the "Corporation").

          WHEREAS Matthews owns or controls a majority of the outstanding
voting shares in the capital of the Corporation; and

          WHEREAS it is a condition of the proposed sale of Series A Preferred
Shares of the Corporation to certain investors that Matthews execute and deliver
this Agreement to the Corporation at the time of the closing of the share
purchase transaction contemplated by such sale;

          NOW THEREFORE THIS AGREEMENT WITNESSETH that in consideration of the
premises and sum of $2.00 now paid by each party to the other (the receipt of
which is hereby acknowledged by each of the parties) the parties hereto hereby
respectively covenant and agree as follows:

1.        Matthews covenants and agrees with the Corporation that:

          (a)  he will not at any time while an officer, employee or shareholder
          of the Corporation or its affiliates (the "Group Companies") or at any
          time within a

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          period of two years thereafter either solely or jointly with any
          person, directly or indirectly, carry on or be engaged or concerned or
          interested or in any way assist in any of the Territories (as
          hereinafter defined) in the manufacture, leasing, distribution or sale
          of any goods or the supply of any services substantially similar to or
          competing with any goods or services which have been manufactured,
          leased, distributed, sold or supplied in the normal course of the
          business by any of the Group Companies except as a shareholder holding
          less than 5.5% of the outstanding shares of any corporation offering
          its shares to the public;

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(b)       the Territories to which paragraph I (a) shall apply are:

               (i)    within the Province of Ontario;

               (ii)   within Canada,

               (iii)  within North America; and

               (iv)   within any municipality, city or town, as the case may be,
                      within which any person, firm, corporation or other entity
                      which is or has been a customer of the Corporation at any
                      time within two years preceding the date on which this
                      Agreement terminates, carries on business;

          (c)  he will not at any time while an officer, employee or shareholder
               of any of the Group Companies or at any time within a period of
               two years thereafter, either on his own account or as agent of
               any person, canvass or solicit or accept orders for any goods or
               services similar to or competing with any goods or services which
               have been leased, sold or supplied in the normal course of the
               business by any of the Group Companies or induce or endeavour to
               induce any such person to cease being a customer of any of the
               Group Companies; and

          (d)  he will not at any time while an officer, employee or shareholder
               of any of the Group Companies or at any time within a period of
               two years thereafter, either on his own account or as agent of
               any person, canvass or solicit for employment any person who is,
               or has been an employee of any of the Group Companies or
               endeavour to induce any such person to cease being an employee of
               any of the Group

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               Companies.

          2.   Any notice or other instrument required or permitted to be given
     to Matthews hereunder shall be in writing and may be given by delivering
     the same addressed to Matthews at 7 Oakeswood #3, Kanata, Ontario. Any
     notice or other instrument required or permitted to be given to the
     Corporation hereunder shall be in writing and may be given by delivering
     the same addressed to the Corporation at 1051 Baxter Road, Ottawa, Ontario.
     Any notice or other instrument aforesaid if delivered shall be deemed to
     have been given or made on the date on which it was delivered. Matthews or
     the Corporation may change his or its address for service from time to time
     by notice given in accordance with the foregoing.

          3.   This Agreement shall be governed by and construed in accordance
     with the laws of the Province of Ontario and the laws of Canada applicable
     therein.

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     4.   This Agreement is not assignable by either party hereto without the
     prior written consent of the other.

     5.   If any covenant or provision in this Agreement is determined to be
     void or unenforceable in whole or in part, it shall not be deemed to affect
     or impair the validity of any other covenant or provision hereof and
     Matthews hereby agrees that all such covenants and provisions are
     reasonable and valid and hereby waives all defences to the strict
     enforcement thereof by the

               IN WITNESS WHEREOF this Agreement has been executed by the
     parties hereto.

     SIGNED, SEALED & DELIVERED    )
          in the presence of:      )
                                   )
                                   )    /s/ Terence H. Matthews
                                        -----------------------

                                        NEWBRIDGE NETWORKS CORPORATION

                                        Per:  /s/ Terence H. Matthews
                                        -----------------------------

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