Method of transferring packets and router device therefor

A router device for receiving packets and transferring each of the packets to one of output lines, each of the packets comprising header information, said header information including a first section containing a label and a second section indicating communication quality of the each of the packets;

• the router device comprising:
• a table having a plurality of entries, each of the entries indicating an identifier of an output line to which an input packet is to be sent and a new label in association with an input label to be extracted from said first section of the input packet,
• a table search unit for searching said table for an entry, using said first section of the received packet as a search key and determining the output line and the new label corresponding to the received packet,
• a header information extractor for extracting contents of the second section of said received packet,
• an output header generator for generating an additional header to be added to said received packet using the new label determined by said table search unit and the communication quality copied from the second section extracted by said header information extractor,
• a line status monitor for monitoring the status of said output lines, and
• a controller for receiving a notice of failure from said line status monitor, and changing contents of said table according to said notice of failure.