Patent ID: 7103274

Claim:
A cross-connect apparatus having first to nth working cross-connects for changing over output paths of n-bit input signals that arrive from respective ones of m-number of input paths, and a connection architecture for inputting first to nth bit data of an input signal that arrives from an ith input path (i=1 to m) to respective ones of ith input terminals of the first to nth working cross-connects and sending bit data that is output from jth output terminals (j=1 to m) of the first to nth working cross-connects to a jth output path, said apparatus comprising: m-number of first logic circuits respectively for calculating the exclusive-OR of the first to nth bit data of an input signal that arrives from an ith input path (i=1 to m); a standby cross-connect having an ith terminal to which is input an output signal of a first logic circuit that corresponds to the ith input path (i=1 to m); m-number of second logic circuits respectively for calculating the exclusive-OR of signals output from the jth terminals (j=1 to m) of the first to nth working cross-connects and of said standby cross-connect; and abnormality detecting means for monitoring output signals of said second logic circuits when the working and standby cross-connects have all been set to the same cross-connect state, and detecting that an abnormality has occurred in any of the n-number of working cross-connects in response to generation of an output signal that differs from that when operation is normal.