| 摘要 |
Methods and apparatus are set forth that perform Format Conversion between bit streams which embed sub-rate circuit data according to different protocols. The invention (1) locates and extracts the sub-rate circuit data embedded, in an input serial bit stream, in accordance with a first predefined protocol (2) aligns the data in a buffer, and (3) creates an output bit stream in which the extracted circuit data is reformatted and inserted in accordance with a second predefined protocol. A programmable bit map driven format conversion module operates the data aligned in the aforementioned buffer. The conversion process is bidirectional and, in one embodiment of the invention, facilitages conversion between a single stage time division multiplexed data format and a two stage time division multiplexed format (e.g. X.50 and I.463) by utilizing the aforesaid bit map driven format conversion technique. More generally, the invention permits conversion between any two predefined protocols, permits great flexibility in network system configuration and permits multiple channels of different format or frame alignments to be converted simultaneously. |
