Patent ID: 8654766

Claim:
A network device coupled to a first network that performs communication using a synchronous multiplexing frame and a second network that performs communication using a data packet or a data frame, the network device comprising: a receiving control unit comprising: a synchronous multiplexing line interface unit that terminates the synchronous multiplexing frame, and a demultiplexing unit that demultiplexes the received synchronous multiplexing frame into a frame for each channel and holds the frames, an interwork control unit that stores an interworking device (IWE) management table holding correspondence information of channel information of a channel and a hierarchized logical path identifier that identifies communication control information of the second network, a logical multiplex frame generating unit that: searches the IWE table by using a key of the channel information, obtains a destination device identifier within the second network and the hierarchized logical path identifier corresponding to the channel information, extracts the frame from the demultiplexing unit, and adds header information including the hierarchized logical path identifier corresponding to the channel information to the extracted frame, and a sending control unit that transmits the generated frame to the second network, wherein the receiving control unit extracts the channel information based on information of the synchronous multiplexing frame, and wherein the receiving control unit: extracts phase information from the synchronous multiplexing frame, and extracts the channel information of the synchronous multiplexing frame based on the phase information.