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Exhibit 13.1

Selected Financial Data

FIVE-YEAR SUMMARY OF SELECTED FINANCIAL DATA (1)

The following selected financial data should be read in conjunction with our
Consolidated Financial Statements. The information set forth below is not
necessarily indicative of results of future operations, and should be read in
conjunction with Managements Discussion and Analysis of Financial Condition
and Results of Operations, and the Consolidated Financial Statements and notes
thereto included in financial statements and supplementary data of this Annual
Report to Stockholders in order to fully understand factors that may affect the
comparability of the financial data presented below.

|                                              |                                                     |                          |         |                                       |         |         |         |         |         |         |         |            |         |   |         |         |         |   |         |         |         | 
|--------------------------------------------- | --------------------------------------------------- | ------------------------ | ------- | ------------------------------------- | ------- | ------- | ------- | ------- | ------- | ------- | ------- | ---------- | ------- | - | ------- | ------- | ------- | - | ------- | ------- | ------- | 
|                                              |                                                     |                          |         | Years Ended December 31,             
|                                              |                                                     |                          |         |                                      
|                                              |                                                     |                          |         | 2003(2)                               |         | 2002(3) |         | 2001(4) |         | 2000(5) |         | 1999(6)(7)
|                                              |                                                     |                          |         |                                       |         |         |         |         |         |         |         |           
|                                              |                                                     |                          |         | (in thousands, except per share data)
|Consolidated Statements of Operations Data:   |                                                     |                          |         |                                       |         |         |         |         |         |         |         |            |         |   |         |         |         |   |         |        
|Revenues                                      |                                                     | $                        | 333,457 |                                       |         | $       | 344,063 |         |         | $       | 327,569 |            |         | $ | 416,850 |         |         | $ | 296,611 |        
|Cost of revenues                              |                                                     |                          | 169,368 |                                       |         |         | 179,957 |         |         |         | 215,956 |            |         |   | 215,303 |         |         |   | 157,911 |        
|                                              |                                                     |                          |         |                                       |         |         |         |         |         |         |         |            |         |   |         |         |         |   |         |        
|                                              | Gross profit                                        |                          |         | 164,089                               |         |         |         | 164,106 |         |         |         | 111,613    |         |   |         | 201,547 |         |   |         | 138,700 |        
|                                              |                                                     |                          |         |                                       |         |         |         |         |         |         |         |            |         |   |         |         |         |   |         |        
|Operating expenses:                           |                                                     |                          |         |                                       |         |         |         |         |         |         |         |            |         |   |         |         |         |   |         |        
|                                              | Research and development                            |                          |         | 66,148                                |         |         |         | 61,658  |         |         |         | 64,169     |         |   |         | 58,828  |         |   |         | 48,343  |        
|                                              | Sales and marketing                                 |                          |         | 40,512                                |         |         |         | 47,625  |         |         |         | 49,385     |         |   |         | 47,463  |         |   |         | 34,425  |        
|                                              | General and administrative                          |                          |         | 28,756                                |         |         |         | 26,370  |         |         |         | 37,323     |         |   |         | 29,172  |         |   |         | 33,947  |        
|                                              | Amortization and write-down of acquired intangibles |                          |         | 4,840                                 |         |         |         | 3,275   |         |         |         |           |         |   |         |        |         |   |         |        |        
|                                              | Securities litigation settlement costs              |                          |         |                                      |         |         |         | 4,443   |         |         |         |           |         |   |         |        |         |   |         |        |        
|                                              | In-process research and development                 |                          |         |                                      |         |         |         | 12,423  |         |         |         |           |         |   |         |        |         |   |         |        |        
|                                              |                                                     |                          |         |                                       |         |         |         |         |         |         |         |            |         |   |         |         |         |   |         |        
|                                              |                                                     | Total operating expenses |         |                                       | 140,256 |         |         |         | 155,794 |         |         |            | 150,877 |   |         |         | 135,463 |   |         |         | 116,715 | 
|                                              |                                                     |                          |         |                                       |         |         |         |         |         |         |         |            |         |   |         |         |         |   |         |        
|Operating income (loss)                       |                                                     |                          | 23,833  |                                       |         |         | 8,312   |         |         |         | (39,264 | )          |         |   | 66,084  |         |         |   | 21,985  |        
|Other income, net                             |                                                     |                          | 11,774  |                                       |         |         | 38,503  |         |         |         | 306,238 |            |         |   | 51,444  |         |         |   | 385,444 |        
|                                              |                                                     |                          |         |                                       |         |         |         |         |         |         |         |            |         |   |         |         |         |   |         |        
|Income before income taxes                    |                                                     |                          | 35,607  |                                       |         |         | 46,815  |         |         |         | 266,974 |            |         |   | 117,528 |         |         |   | 407,429 |        
|Income taxes                                  |                                                     |                          | 8,902   |                                       |         |         | 14,981  |         |         |         | 101,450 |            |         |   | 39,960  |         |         |   | 158,359 |        
|                                              |                                                     |                          |         |                                       |         |         |         |         |         |         |         |            |         |   |         |         |         |   |         |        
|Net income                                    |                                                     | $                        | 26,705  |                                       |         | $       | 31,834  |         |         | $       | 165,524 |            |         | $ | 77,568  |         |         | $ | 249,070 |        
|                                              |                                                     |                          |         |                                       |         |         |         |         |         |         |         |            |         |   |         |         |         |   |         |        
|Basic net income per share                    |                                                     | $                        | 0.31    |                                       |         | $       | 0.38    |         |         | $       | 2.03    |            |         | $ | 0.97    |         |         | $ | 3.20    |        
|                                              |                                                     |                          |         |                                       |         |         |         |         |         |         |         |            |         |   |         |         |         |   |         |        
|Shares used in basic per share computations   |                                                     |                          | 85,849  |                                       |         |         | 83,380  |         |         |         | 81,381  |            |         |   | 80,201  |         |         |   | 77,723  |        
|                                              |                                                     |                          |         |                                       |         |         |         |         |         |         |         |            |         |   |         |         |         |   |         |        
|Diluted net income per share                  |                                                     | $                        | 0.31    |                                       |         | $       | 0.37    |         |         | $       | 1.98    |            |         | $ | 0.91    |         |         | $ | 3.05    |        
|                                              |                                                     |                          |         |                                       |         |         |         |         |         |         |         |            |         |   |         |         |         |   |         |        
|Shares used in diluted per share computations |                                                     |                          | 87,470  |                                       |         |         | 85,292  |         |         |         | 83,638  |            |         |   | 84,800  |         |         |   | 81,657  |        
|                                              |                                                     |                          |         |                                       |         |         |         |         |         |         |         |            |         |   |         |         |         |   |         |        

|                                                 |  |                                                    |           |      |  |      |           |      |  |      |           |  |  |   |           |  |  |   |         | 
|------------------------------------------------ |  | -------------------------------------------------- | --------- | ---- |  | ---- | --------- | ---- |  | ---- | --------- |  |  | - | --------- |  |  | - | ------- | 
|                                                 |  | As of December 31,                                
|                                                 |  |                                                   
|                                                 |  | 2003                                               |           | 2002 |  | 2001 |           | 2000 |  | 1999
|                                                 |  |                                                    |           |      |  |      |           |      |  |     
|                                                 |  | (in thousands, except per share and employee data)
|Consolidated Balance Sheets Data:                |  |                                                    |           |      |  |      |           |      |  |      |           |  |  |   |           |  |  |   |         | 
|Cash, cash equivalents and marketable securities |  | $                                                  | 1,091,568 |      |  | $    | 999,217   |      |  | $    | 958,711   |  |  | $ | 878,447   |  |  | $ | 734,119 | 
|Working capital                                  |  | $                                                  | 863,525   |      |  | $    | 784,790   |      |  | $    | 774,297   |  |  | $ | 744,723   |  |  | $ | 583,357 | 
|Total assets                                     |  | $                                                  | 1,317,716 |      |  | $    | 1,232,992 |      |  | $    | 1,146,859 |  |  | $ | 1,135,175 |  |  | $ | 900,787 | 
|Stockholders equity                             |  | $                                                  | 985,156   |      |  | $    | 918,789   |      |  | $    | 838,605   |  |  | $ | 819,665   |  |  | $ | 645,064 | 
|Book value per share                             |  | $                                                  | 11.32     |      |  | $    | 10.89     |      |  | $    | 10.21     |  |  | $ | 10.15     |  |  | $ | 8.16    | 
|Number of employees                              |  |                                                    | 773       |      |  |      | 857       |      |  |      | 843       |  |  |   | 959       |  |  |   | 722     | 

(1)  Certain prior period amounts have been reclassified to conform to the
current presentation. See Note 1 of the Notes to Consolidated Financial
Statements.

(2)  2003 included the reversal of $2.5 million in purchase commitments reserve,
change in warranty estimate methodology and reversal of $4.6 million in
reserve, $6.6 million in severance and related costs for workforce reduction,
$2.8 million write-down of an impaired intangible asset, $2.0 million in
amortization of acquired

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intangible assets, $1.0 million write-down of an impaired investment, and $1.4
million in unrealized gains on our Cisco Systems, Inc. (Cisco) securities
investment. See Managements Discussion and Analysis of Financial Condition and
Results of Operations for additional information.

(3)  2002 included a
$0.9 million charge resulting from the 2002 workforce reduction, $3.3
million in amortization of acquired intangibles, $12.4 million write-off of
acquired in-process research and development costs, $4.4 million of litigation
settlement costs, $18.4 million in unrealized gains on our Cisco securities
investment and a $13.6 million accrued distribution payment from Marconi
Communications, Inc. (Marconi). See Managements Discussion and Analysis of
Financial Condition and Results of Operations for additional information.

(4)  2001 included $18.9 million in charges to excess and obsolete inventory,
$13.4 million in purchase commitments, $4.3 million charge to cost of revenues, $9.3
million charge to provision for doubtful accounts, $4.9 million in facility
lease impairment charges, $1.4 million related to fixed asset write-downs,
severance costs and foreign sales office closures, $2.3 million write-down of
an impaired investment, and $13.6 million in accrued distribution payment from
Marconi. 2001 also included $285.7 million in unrealized gains on our Cisco
securities investment from the application of Statement of Financial Accounting
Standards (SFAS) No. 133, Accounting for Derivative Instruments and
Hedging Activities, and related net gains on our Cisco holdings during the
year. See Managements Discussion and Analysis of Financial Condition and
Results of Operations for additional information.

(5)  2000 included $42.9 million from Marconi as settlement of outstanding
litigation and a subsequent distribution payment, and GVN Technologies, Inc.
(GVN) acquisition related costs.

(6)  1999 included a $379.3 million gain recognized upon conversion of an
investment into Cisco common stock.

(7)  Amounts have been restated to reflect the acquisition of GVN in 2000
accounted for as a pooling of interests; number of employees has not been
restated.

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