COMMUNICATION DISCONNECTING CIRCUIT IN FAILURE TIME OF WIDE AREA NETWORK COMMUNICATION DEVICE

PROBLEM TO BE SOLVED: To certainly disconnect communication control elements from a line in a higher speed than that in a control method by a software at the time of a failure of the communication control elements in a circuit which performs Ethernet communications with other information devices using the communication control elements. SOLUTION: When a monitoring device and a circuit disconnecting device are connected to the communication circuit, and monitor the communication control elements, the circuit disconnecting device certainly and physically disconnects the elements from the line in high speed so as not to affect the whole line by incorrect output or runaway if failure of the communication control circuit is detected. Moreover, soundness is confirmed by comparing systems since the monitoring device uses a multiple system configuration. Therefore, it is possible to prevent overlooking/incorrect detection of the failure of the communication control device by potential failure of the monitoring device, and a high reliable system can be built. COPYRIGHT: (C)2009,JPO&INPIT