A central monitoring system of a multiplexer subscriber loop carrier

Claim 1

A central monitoring system of a multiplex subscriber loop carrier connecting a plurality of first subscriber lines respectively connected with subscriber terminals and a plurality of second subscriber lines connected to a local switch for switching the second subscriber lines, the multiplex subscriber loop carrier (SLC) comprising: a remote terminal (RT) for multiplexing/demultiplexing the first subscriber lines to/from a carrier line carrying a plurality of channels, said remote terminal comprising a first subscriber line tester (SLT1) for testing the first subscriber lines so as to detect a fault on the first subscriber line, said first subscriber line tester transmitting fault information about said fault; and a central office terminal (COT) for multiplexing/demultiplexing the second subscriber lines to/from said carrier line, said central office terminal comprising a dummy fault generating circuit for representing said fault, upon receiving fault information about said fault via said carrier line from said first subscriber line tester said dummy fault generating circuit being connected via a transfer switch to one of the second subscriber lines that corresponds to said first subscriber line having said fault thereon, wherein the local switch comprises a second subscriber line tester (SLT2) for testing said second subscriber lines, whereby said second subscriber line tester detects said dummy fault generating circuit as a message informing that said fault is on said first subscriber line which corresponds to said second subscriber line having said dummy fault generating circuit connected thereto.