Patent ID: 7076165

Claim:
An apparatus comprising: an optical transponder, the optical transponder including: at least one opto-electrical converting means for receiving optical signal as an input optical signal, and converting the received optical signal into a electrical signal; at least one demultiplexing means for demultiplexing the converted electrical signal; information adding means for adding maintenance information, monitoring information, and error correction information to each of demultiplexed signals outputted from the demultiplexing means; detecting and correcting means for receiving the demultiplexed signals from the demultiplexing means, detecting the maintenance information, monitoring information, and errors contained in each of the demultiplexed signals, and correcting the detected errors; at least one multiplexing means for receiving and multiplexing signals respectively outputted from the information adding means and the detecting and correcting means; at least one optical transmitting means for transmitting a signal outputted from the multiplexing means as an output signal; and control means for generating a control signal for processing of the maintenance information and monitoring information, and correction of errors, applying the control signal to the detecting and correcting means, receiving the maintenance information, monitoring information, and error correction information from the detecting and correcting means, and signal-processing the received information, wherein the optical transponder operates to perform add/drop operation functions of optical channels in an optical transport system connecting an external network and an optical transport network.