Transporting multiple low-speed data streams across a high-speed communication link

Abstract

A method and apparatus for transporting multiple low-speed data streams across a high-speed communication channel or link. In one embodiment of the method, first and second data streams are transmitted at first and second data transmission rates, respectively, via an optical cable, wherein the first and second data transmission rates are distinct. Components of the first data stream are transmitted via the optical cable between transmission of components of the second data stream via the optical cable, and components of the second data stream are transmitted via the optical cable between transmission of components of the first data stream via the optical cable.

What is claimed is: 
     
         1 . A method comprising:
 creating first data words from data of a first received data stream having a first data rate, each of the first data words having a length of N bits;   creating second data words from data of a second received data stream having a second data rate different from the first data rate, each of the second data words having the same length of N bits as the first data words;   transmitting the first data words over an optical cable at first time intervals; and   transmitting the second data words over the optical cable at second time intervals.   
     
     
         2 . The method of  claim 1  further comprising:
 scheduling the first data words for transmission over the optical cable; 
 scheduling the second data words for transmission over the optical cable; 
 determining that one of the first data words and one of the second data words are scheduled to be transmitted over the optical cable at the same time; 
 rescheduling the transmission of the one of the first data words before or after transmission of the one of the second data words. 
 
     
     
         3 . The method of  claim 1 , wherein a plurality of the second data words are transmitted over the optical cable between transmission of a pair of the first data words over the optical cable. 
     
     
         4 . The method of  claim 1 , wherein the first and second received data streams are asynchronous with respect to each other. 
     
     
         5 . The method of  claim 1 , wherein each of the first time intervals are greater than the second time intervals. 
     
     
         6 . The method of  claim 1  wherein the first and second received data streams are received from first and second devices, respectively, that transmit the first and second data streams in accordance with first and second protocols, respectively, wherein the first and second protocols are distinct from each other. 
     
     
         7 . The method of  claim 1 , further comprising mapping N bits of the first received data stream to M bits using an encoder, and transmitting the M bits via the optical cable as one of the first data words. 
     
     
         8 . An apparatus comprising:
 a circuit for creating first data words from data of a first received data stream having a first data rate, each of the first data words having a length of N bits, and for creating second data words from data of a second received data stream having a second data rate different from the first data rate, each of the second data words having the same length of N bits as the first data words; and   a circuit configured to transmit the first data words over an optical cable at first time intervals, and to transmit the second data words over the optical cable at second time intervals.   
     
     
         9 . The apparatus of  claim 8 , wherein a plurality of the second data words are transmitted over the optical cable between transmission of a pair of the first data words over the optical cable. 
     
     
         10 . The apparatus of  claim 8 , wherein the first and second received data streams are asynchronous with respect to each other. 
     
     
         11 . The apparatus of  claim 8 , wherein each of the first time intervals are greater than the second time intervals. 
     
     
         12 . The apparatus of  claim 8 , wherein the first and second received data streams are received from first and second devices, respectively, that transmit the first and second data streams in accordance with first and second protocols, respectively, wherein the first and second protocols are distinct from each other. 
     
     
         13 . The apparatus of  claim 8 , further comprising an encoder configured to map N bits of the first received data stream to M bits, and a circuit configured to transmit the M bits via the optical cable as one of the first data words. 
     
     
         14 . A method comprising:
 receiving data of a first data stream from a first device at a first data rate;   receiving data of a second data stream from a second device at a second data rate, which is different from the first data rate;   wherein the first data stream is destined only for a first receiving device;   wherein the second data stream is destined only for a second receiving device;   creating first data words from data of the first data stream, wherein each of the first data words has a length of N bits;   creating second data words from data of the second data stream, wherein each of the first data words has the same length of N bits;   transmitting the first data words over an optical cable at first time intervals;   transmitting the second data words over the optical cable at second time intervals;   
     
     
         15 . The method of  claim 14 , wherein a plurality of the second data words are transmitted over the optical cable between transmission of a pair of the first data words over the optical cable.