Protected optical switching matrix

Abstract

A protected optical switch matrix having N inputs and N outputs and including an optical switching fabric (S 2 -S 2 ′), an input interface (S 1 ) performing wavelength conversion and an output interface (S 3 ) performing wavelength filtering. The input interface (S 1 ) and the output interface (S 3 ) are protected by redundancy provided by r redundant units for E working units where r is a number very much less than E.

1 . A protected optical switch matrix having N inputs and N outputs and including an optical switching fabric (S 2 -S 2 ′), an input interface (S 1 ) performing wavelength conversion and an output interface (S 3 ) performing wavelength filtering, 
 characterized in that the input interface (S 1 ) and the output interface (S 3 ) are protected by redundancy provided by r redundant units for E working units where r is a number very much less than E.  
 
     
     
         2 . A matrix according to    claim 1   , characterized in that the input interface includes at least one group of E working wavelength converters (WC 11 , . . . , WCm 1 ) and r redundant converters (WC(m+1) 1 ) which are all tuned permanently to the same wavelength.  
     
     
         3 . A matrix according to    claim 1   , characterized in that the input interface includes at least one group of E working wavelength converters (WC 12 , . . . , WCp 2 , WC 14 , . . . , WCN 4 ; WC 16 , . . . , WCp 6 ) and r redundant converters (WC(p+1) 2 ; WC(N+1) 4 ; WC(p+1) 6 ) which can all be tuned in the same band of wavelengths.  
     
     
         4 . A matrix according to    claim 1   , characterized in that the input interface includes at least one group of E working wavelength converters (WC 13 , . . . , WCN 3 ; WC 15 , . . . , WCm 5 ) which are all tuned permanently to E respective different wavelengths and r redundant converters (WC(N+1) 3 ; WC(m+1) 5 ) which can all be tuned to any one of those E wavelengths.  
     
     
         5 . A matrix according to    claim 1   , characterized in that the output interface includes at least one group of E working wavelength filters (F 11 , . . . , Fp 1 ; F 13 , . . . , FN 3 ; F 15 , . . . , Fp 5 ) and r redundant converters (F(p+1) 1 ; F(N+1) 3 ; F(p+1) 5 ) which can all be tuned to the same range of wavelengths.  
     
     
         6 . A matrix according to    claim 1   , characterized in that the output interface includes at least one group of E working wavelength filters (F 12 , . . . , Fp 2 ) and r redundant converters (F(m+1) 2  which are all tuned permanently to the same wavelength.  
     
     
         7 . A matrix according to    claim 1   , characterized in that the output interface includes at least one group of E working wavelength filters (F 14 , . . . , FN 4 ; F 16 , . . . , Fp 6 ) which are all tuned permanently to E respective different wavelengths and r redundant converters (F(N+1) 4 ; F(p+1) 6 ) which can all be tuned to any one of those E wavelengths.