METHOD AND SYSTEM FOR DETECTING FAILURE OF RING NETWORK

摘要

A pair of transmission lines (14), (15), one for a current system and the other a standby system, pass through child stations (12) in opposite directions from/to a parent station (11). Each child station (12) has a switch for connecting the current system transmission line (14) to the standby system transmission line (15) based on control information from the parent station (11) to form a small loop passing through the parent station (11). A failed part is found by circulating a test cell from the parent station (11) through the small loop, and then the child stations (12) adjacent to the failed part are controlled to form a turn-back loop to maintain the communication. After being recovered from the failure, the turn-back loop is canceled based on control information from the parent station (11), and the system including the recovered child station (12) is recovered to the initial one.