Patent ID: 6870859

Claim:
A multiplex system of tributary signals including a transmitter for multiplexing a plurality of tributary signals supplied from a plurality of upstream signal paths onto a multiplex signal to be transmitted at every fixed interval, a receiver for demultiplexing the multiplex signal received onto a plurality of tributary signals to be supplied to a plurality of downstream signal paths, and a main signal path for transmitting the multiplex signal from the transmitter to the receiver, said transmitter comprising: a plurality of transmission side tributary circuits installed as many as the number of the upstream signal paths for assigning to individual tributary signals frame information and different identification codes without including section overhead information for the multiplex signal, the frame information indicating a unit of the tributary signals in the multiplex signal, and the different identification codes being associated with the upstream signal paths, respectively; and a multiplexer for multiplexing outputs of said plurality of transmission side tributary circuits onto the multiplex signal to be supplied to the main signal path at every fixed interval, and said receiver comprising: a demultiplexer for demultiplexing the multiplex signal onto a same number of tributary signals as the tributary signals multiplexed; a plurality of receiving side tributary circuits installed as many as the number of tributary signals multiplexed onto multiplex signal for supplying the downstream transmission paths with the tributary signals output from said demultiplexer, at least one of said plurality of receiving side tributary circuits detecting its frame information and making a decision of its identification code in response to the frame information detected; and a distribution circuit installed between said demultiplexer and said receiving side tributary circuits for carry out switching of output destinations of the tributary signals supplied from said demultiplexer, the switching being implemented for the each unit of the tributary signals in the multiplex signal in response to a decision result of said at least one of said plurality of receiving side tributary circuits.