EXHIBIT 21

Tellabs, Inc. and Subsidiaries

Subsidiaries of the Registrant

as of December 28, 2007



|                                                             |  |                                            
|------------------------------------------------------------ |  | -------------------------------------------
|Name                                                         |  | State or Other Jurisdiction ofIncorporation
|Tellabs Operations, Inc.                                     |  | Delaware                                   
|Tellabs Japan, Inc.                                          |  | Delaware                                   
|Tellabs International, Inc.                                  |  | Illinois                                   
|Tellabs Communications Canada Ltd.                           |  | Canada                                     
|Tellabs do Brazil, Ltda.                                     |  | Brazil                                     
|Tellabs H.K. Limited                                         |  | Hong Kong                                  
|Tellabs Pty Limited                                          |  | Australia                                  
|Tellabs International de Mexico S.A. de C.V.                 |  | Mexico                                     
|Tellabs Asia Pacific Pte Ltd                                 |  | Singapore                                  
|Tellabs (Thailand) Co., Ltd.                                 |  | Thailand                                   
|Tellabs Korea Limited                                        |  | Korea                                      
|Tellabs India Private Limited                                |  | India                                      
|Tellabs Communications International Limited                 |  | China                                      
|Tellabs Communication Technologies (Shanghai) Limited        |  | China                                      
|Tellabs K.K.                                                 |  | Japan                                      
|Tellabs de Venezuela, S.A.                                   |  | Venezuela                                  
|Tellabs Communications (Malaysia) Sdn. Bhd.                  |  | Malaysia                                   
|Tellabs (Malaysia) Sdn. Bhd. (49% joint venture)             |  | Malaysia                                   
|Tellabs Philippines, Inc.                                    |  | Philippines                                
|Tellabs Holdings, B.V.                                       |  | The Netherlands                            
|Tellabs Enterprises B.V.                                     |  | The Netherlands                            
|Tellabs Oy                                                   |  | Finland                                    
|Kiinteisto Oy Mestarinkaarre                                 |  | Finland                                    
|Kiinteisto Oy Sinimaentie 6                                  |  | Finland                                    
|Tellabs Denmark A/S                                          |  | Denmark                                    
|Tellabs Communications (India) Private Limited               |  | India                                      
|Kring  Tellabs India Private Limited                        |  | India                                      
|Tellabs Holdings, Ltd.                                       |  | Ireland                                    
|Tellabs (Ireland) Ltd.                                       |  | Ireland                                    
|Tellabs Ltd.                                                 |  | Ireland                                    
|Tellabs Research Ltd.                                        |  | Ireland                                    
|Tellabs Communications Ireland Limited                       |  | Ireland                                    
|Tellabs Communications Technologies                          |  | Ireland                                    
|Tellabs EMEA Holdings, Ltd.                                  |  | Ireland                                    
|Tellabs AB                                                   |  | Sweden                                     
|Tellabs South Africa (S.A.) (Proprietary) Limited            |  | South Africa                               
|Tellabs SAS                                                  |  | France                                     
|Tellabs Italia S.r.l.                                        |  | Italy                                      
|Tellabs Netherlands B.V.                                     |  | The Netherlands                            
|Tellabs Poland Sp. z o.o.                                    |  | Poland                                     
|Tellabs Southern Europe s.a. Sociedad Unipersonal (Spain)    |  | Spain                                      
|Tellabs Deutschland GmbH                                     |  | Germany                                    
|Tellabs Austria Vertriebs GmbH                               |  | Austria                                    
|Tellabs Norway AS                                            |  | Norway                                     
|Tellabs U.K. Ltd.                                            |  | United Kingdom                             
|Tellabs Communications UK Limited                            |  | United Kingdom                             
|E. Coherent Communications Systems Limited                   |  | United Kingdom                             
|Tellabs North America, Inc.                                  |  | Delaware                                   
|Tellabs Petaluma, Inc.                                       |  | Delaware                                   
|Tellabs Vienna, Inc.                                         |  | Delaware                                   
|Advanced Fibre Technology Communications (Hong Kong) Limited |  | Hong Kong                                  
|Hangzhou AFTEK Communication Company, Ltd.                   |  | China                                      
|Advanced Fibre Communications (HK) Limited                   |  | Hong Kong                                  
|AFC Foreign Sales Corporation                                |  | U.S. Virgin Islands                        



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|                                                        |  |               
|------------------------------------------------------- |  | --------------
|Tellabs Bedford, Inc.                                   |  | Delaware      
|AccessLan India                                         |  | India         
|Advanced Fibre Communications (India) Private Limited   |  | India         
|Tellabs International GmbH                              |  | Switzerland   
|Advanced Fibre Communications Mexico S. de R.L. de C.V. |  | Mexico        
|Advanced Fibre Communications International Limited     |  | Cayman Islands
|Advanced Fibre Communications U.K. Limited              |  | United Kingdom
|AFC Harris Multimedia Communications Private Limited    |  | Mauritius     
|AFC Harris Multimedia Communications Limited            |  | India         
|Tellabs Mexico, Inc.                                    |  | Delaware      
|Tellabs de Mexico, S.A. de C.V.                         |  | Mexico        
|Tellabs TG, Inc.                                        |  | Delaware      
|Tellabs Transport Group, Inc.                           |  | Quebec        
|Tellabs Nevada Holdings Corporation                     |  | Nevada        
|Tellabs Treasury Holdings Corporation                   |  | Nevada        
|Tellabs Equity Holdings Corporation                     |  | Nevada        
|Tellabs Securities Holdings Corporation                 |  | Nevada        
|Tellabs Reston, Inc.                                    |  | Delaware      
|Tellabs San Jose, Inc.                                  |  | Delaware      
|Future Networks, Inc.                                   |  | Georgia