Patent ID: 6253335
Filing Date: 2001-06-26
Classification: H04L

Abstract:
A network abnormality recovery method in a network comprising a plurality of station units connected by a main data transmission line like a ring enabling circular transmission of communication data in digital form and adopting a master/slave method as a communication method, wherein said plurality of station units consist of one master station unit operating as a master and slave station units operating as slaves and wherein said network comprises one or more sub data transmission lines being provided separately from the main data transmission line for connecting said station units, said method comprising the steps of:executing monitor processing of monitoring a communication state in said network;executing abnormality determination processing of determining whether or not the network communication state is abnormal upon reception of the monitor processing result; andwhen it is determined that the network communication state is abnormal as a result of the abnormality determination processing, executing route switch control of switching a route of communication data generated by each slave station unit from the main data transmission line to the sub data transmission line and executing maintaining information transmission processing of transmitting at least network maintaining information required for maintaining the network communication function to said master station unit over the sub data transmission line set by the route switch control, by each of said plurality of station units.