Patent ID: 7769257

Claim:
A signal speed converting apparatus comprising: a first optical interface, connected to a first optical line group including at least one optical line, for transmitting and receiving information frames with a first format as a serial optical signal or a logical group of parallel optical signals; a plurality of second optical interfaces connected to a second optical line group for transmitting and receiving information frames with a second format as optical signals; and a speed converting unit located between the first optical interface and the second optical interface, said first optical interface having a first framer for terminating the information frames in the first format to be transmitted to or received from said first optical line group and converting original information signals in the information frames into a serial signal train or a logical group of parallel signal trains, wherein said speed converting unit converts the serial signal train or the parallel signal trains input from said first framer into a plurality of signal trains each including interleaved original information signals by cyclically allocating the serial signal train or the parallel signal trains to a plurality of internal lines corresponding to the second optical interfaces, and wherein each of said second optical interfaces has a second framer for converting the interleaved signal train on one of said internal lines corresponding to the second framer into the information frame in the second format, the signal speed converting apparatus further comprising a plurality of management information inserting units for duplicating management information to be communicated with an opposite signal speed converting apparatus located at opposite side via external WDM optical paths and inserting the management information into the plurality of signal trains individually, and management information extracting units for extracting management information from signal trains transmitted from the opposite signal speed converting apparatus.