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                                                                    EXHIBIT 11.1
                                                                                
                         NEWBRIDGE NETWORKS CORPORATION
                                        
                       COMPUTATION OF EARNINGS PER SHARE
                                        
              (Accounting principles generally accepted in Canada)
         (Canadian dollars, amounts in thousands except per share data)
                                  (Unaudited)

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                                                      FISCAL QUARTER ENDED  TWO FISCAL QUARTERS ENDED
                                                      --------------------  --------------------------
                                                        Nov 2,    Oct 27,       Nov 2,      Oct 27,
                                                         1997      1996         1997         1996
                                                      ---------   --------  -----------   -----------
<S>                                                   <C>         <C>       <C>           <C>
BASIC EARNINGS PER SHARE
 
 Net earnings                                         $ 57,993    $ 62,781   $122,347      $123,582
                                                      ========    ========   ========      ========
 Common shares outstanding                                                            
  at the beginning of the period                       174,245     169,754    171,859       168,676
                                                                                      
 Weighted average number of Common Shares                                             
   issued, net of Common Shares                                                       
   repurchased, during the period                          488         478      1,971         1,060
                                                      --------    --------   --------      --------
 Weighted average number of Common Shares                                             
   outstanding during the period                       174,733     170,232    173,830       169,736
                                                      ========    ========   ========      ========
                                                                                      
 Basic earnings per share                             $   0.33    $   0.37   $   0.70      $   0.73
                                                      ========    ========   ========      ========
FULLY DILUTED EARNINGS PER SHARE                                                      
                                                                                      
 Earnings before imputed earnings                     $ 57,993    $ 62,781   $122,347      $123,582
                                                                                      
 After tax imputed earnings from the investment                                       
   of funds received through dilution                    4,363       2,715      8,342         5,598
                                                      --------    --------   --------      --------
                                                                                      
 Adjusted net earnings                                $ 62,356    $ 65,496   $130,689      $129,180
                                                      ========    ========   ========      ========
 Weighted average number of Common Shares                                             
   outstanding during the period                       174,733     170,232    173,830       169,736
                                                                                      
 Weighted average common share                                                        
   equivalents based on conversion of                                                 
   outstanding stock options                            15,783      13,899     15,953        13,198
                                                      --------    --------   --------      --------
 Weighted average number of Common                                                    
   Shares and equivalents outstanding                                                 
   during the period                                   190,516     184,131    189,783       182,934
                                                      ========    ========   ========      ========
                                                                                      
 Fully diluted earnings per share                     $   0.33    $   0.36   $   0.69      $   0.71
                                                      ========    ========   ========      ========
EARNINGS PER SHARE EXPRESSED IN U.S. DOLLARS                                          
                                                                                      
 Daily average exchange rate of a Canadian                                            
   dollar for U.S. dollars as reported by the                                         
   Federal Reserve Bank of New York                   $ 0.7204    $ 0.7322   $ 0.7223      $ 0.7316
                                                                                      
 Basic earnings per share, in U.S. dollars            $   0.24    $   0.27   $   0.51      $   0.53
                                                      ========    ========   ========      ========
                                                                                      
 Fully diluted earnings per share, in U.S. dollars    $   0.24    $   0.26   $   0.50      $   0.52
                                                      ========    ========   ========      ========
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