| 摘要 |
PROBLEM TO BE SOLVED: To certainly determine normal nodes in a communication network constituting a plurality of nodes and replace the minimum number of nodes to remove failure.SOLUTION: A failure monitoring system includes first to third nodes 13, 11, and 15 connected in series with first links L1. The first links L1 have first switch means SW1 between a second node 11 and a third node 15. The first node 13 transmits a monitoring signal toward the third node 15 via the first links, and the third node receives the monitoring signal and then transmits a reply signal to the monitoring signal. The first node switches the state of the first switch means between a passing state of passing signals and a folding state of folding signals, and determines if the first to third nodes are normal on the basis of the reply signal and the presence/absence of the reception of the monitoring signal to be folded.SELECTED DRAWING: Figure 2 |
