Patent ID: 7515532

Claim:
A method for preventing duplication and loss of exchanges, sequences, and frames, comprising: receiving data for transmission over a fiber optics network; decoding each piece of the data; re-encoding each piece of the data to include a Generic Framing Procedure header having a sequence identification number and session identification number; transmitting each piece of the data over the fiber optics network, the fiber optics network including a working path and a backup path, the working path and the backup path having different lengths; buffering the data received on the working path and buffering the data received on the backup path at a destination node, wherein an amount of the data buffered is dependent on a path length differential between the path lengths of the working path and the backup path; identifying each piece of the data by its sequence identification number and session identification number, when switching to the backup path from the working path; in response to a broken line in the working path, receiving the data from the backup path; checking the sequence identification number in the header for each piece of the data received on the working path and the backup path, wherein the sequence identification numbers are transmitted down the working path and the backup path at the same time; keeping track of the sequence identification number for each piece of data received on the working path and the backup path to determine at least one of a duplicate and a lost frame; in response to receiving a duplicate frame from the data from the backup path, discarding the duplicate frame from the data from the backup path; in response to losing a frame from the data from the working path, passing the frame from the data from the working path to its destination; in response to detecting a corrupted frame on the working path, locating a corresponding frame received on the backup path and substituting the corrupted frame with the corresponding frame; and in response to a bit error rate exceeding a preset level, switching to the backup path from the working path.