COMMUNICATION NETWORK AND LOGIC PATH SELECTION METHOD

摘要

PROBLEM TO BE SOLVED: To constitute an information transmission network corresponding to the height of reliability or economy by previously setting plural logic paths different in transmission quality between the node devices of a start and an end, recognizing the identifier of a service class contained in an information signal and selecting one of the logic paths. SOLUTION: In the node devices A-C, bus management parts 20, control communication parts 21 and main signal processing parts 22 previously set the plural logic paths different in transmission quality between the node devices at the start and the end and transmit the information signal. The information signal contains the identifiers of the service classes A-C and the processing part 22 selects the logic path in accordance with the class that the management parts 20 of the device A at the start obtains by recognition. The class A switches the two present/standby paths without hit. The class B or C does not set a bypass or compensate data loss when a fault occurs. Thus, highly reliable communication information does not lack even if the fault occurs and communication information which does not request reliability can economically be transmitted.