<PAGE>

                                                                    EXHIBIT 11.1

                        NEWBRIDGE NETWORKS CORPORATION

                       COMPUTATION OF EARNINGS PER SHAdE

             (Accounting principles generally accepted in Canada)
        (Canadian dollars, amounts in thousands except per share data)
                                  (Unaudited)

<TABLE>
<CAPTION>


                                              Fiscal quarters ended  Two fiscal quarters ended
                                              ---------------------  -------------------------

                                                    Oct 31,    Nov 1,       Oct 31,    Nov 1,
                                                     1999       1998         1999       1998
                                                   --------  ---------    --------  --------
<S>                                                <C>        <C>         <C>       <C>
Basic earnings per share

 Net earnings                                      $301,709   $ 53,314    $348,995   $ 88,834
                                                   ========   ========    ========   ========

 Common Shares outstanding
  at the beginning of the period                    180,597    176,558     180,105    175,686

 Weighted average number of Common Shares
   issued during the period                             266        208         526        744
                                                   --------   --------    --------   --------

 Weighted average number of Common Shares
   outstanding during the period                    180,863    176,766     180,631    176,430
                                                   ========   ========    ========   ========

 Basic earnings per share                          $   1.67   $   0.30    $   1.93   $   0.50
                                                   ========   ========    ========   ========

Fully diluted earnings per share

 Earnings before imputed earnings                  $301,709   $ 53,314    $348,995   $ 88,834

 After tax imputed earnings from the investment
   of funds received through dilution                11,826         --      22,719         --
                                                   --------   --------    --------   --------

 Adjusted net earnings                             $313,535   $ 53,314    $371,714   $ 88,834
                                                   ========   ========    ========   ========

 Weighted average number of Common Shares
   outstanding during the period                    180,863    176,766     180,631    176,430
                                                   ========   ========    ========   ========

 Weighted average common share
   equivalents based on conversion of
   outstanding stock options                         25,078         --      22,861         --
                                                   --------   --------    --------   --------

 Weighted average number of Common
   Shares and equivalents outstanding
   during the period                                205,941    176,766     203,492    176,430
                                                   ========   ========    ========   ========

 Fully diluted earnings per share                  $   1.52   $   0.30    $   1.83   $   0.50
                                                   ========   ========    ========   ========

</TABLE>

                                (Page 50 of 52)