| 摘要 |
PROBLEM TO BE SOLVED: To shorten a temporary stop period of communication when a fault occurs by looping back a signal line that stores an entire logic communication path in the fault occurrence mode and then canceling the loopback of the signal line according to the restoring state of the fault. SOLUTION: For instance, a fault occurs on a communication path set between the nodes B and C and the interruption of communication is detected on a logic circuit by the receiving part of a physical layer part 102 of the node C. When a fault detection signal is outputted from the part 102 to a main control part 101 under such conditions, the part 101 outputs a loopback instruction signal to the part 102. A selector of the part 102 cuts the electric signal that is outputted from the receiving part and to be inputted to an ATM switch 104 and inputs the electric signal outputted from the switch 104 to this switch again to perform the loopback of a physical communication path. Furthermore, the part 101 outputs a prescribed ATM cell via a monitor/control path to instruct the loopback to the node B. |
