公开(公告)号：JPH03117953A

公开(公告)日：1991-05-20

申请号：JP25498990

申请日：1990-09-25

Applicant: KOREA ELECTRONICS TELECOMM ,  KOREA TELECOMMUNICATION

Inventor： YON FUI RI ,  YON SHIKU BEKU ,  SOKU GI RI ,  KUN U RI ,  CHIYON OKU CHIYAA

IPC: H04M3/22 ,  H04M7/06 ,  H04Q3/00

Abstract: PURPOSE: To improve the reliability of a system by making a level 3-3 connection network duplex for changing modules through the normal procedures as the time of the occurrence of a fault. CONSTITUTION: A signal relay system constituted mainly of the duplex level 3-3 connection network consists of level 3-3 connection networks 100a and 100b, a signal message processing module 110, a signal network management module 120, an O/M(operation and maintenance) system 130 and a terminal 140. Consequently, many level 2 units and modules 110 and 120 are not unavailable, namely available even if a fault occurs in one level 3-3 connection network. A time margin for maintenance of one route where a fault occurred and another route free from the occurrence of a fault are used to perform the maintenance. Thus, modules are changed through normal procedures.