Patent ID: 6061329
Filing Date: 2000-05-09
Classification: H04J

Abstract:
An SDH multiplex transmission system comprising a transmission terminal apparatus and a reception terminal apparatus that are connected to each other through a plurality of working channels and at least one spare channel to be used instead of any one of said working channels when a failure occurs in any one of said working channels, in which:the transmission terminal apparatus loads predetermined information into an overhead of an STM frame and transmits the STM frame to said spare channel, said predetermined information indicating whether or not said spare channel is used instead of any one of said working channels by making said predetermined information in agreement with the SDH standards when said spare channel is used instead of any one of said working channels, and by making said predetermined information in disagreement with the SDH standards when said spare channel is not used instead of any one of said working channels; andthe reception terminal apparatus monitors an STM frame received through the spare channel, and if the received STM frame includes in its overhead said predetermined information which is in disagreement with the SDH standards, said reception terminal apparatus determines that the spare channel is not used instead of any one of said working channels.