| 摘要 |
<p>PROBLEM TO BE SOLVED: To restrain unnecessary LOC detection involving switching of redundant interfaces.SOLUTION: A communication device 102 comprises a redundant UNI side LIU 10 and UNI side LIU 20. The communication device 102 determines that the connection state with an external device is normal if at least one of the UNI side LIU 10 and UNI side LIU 20 has normally received a CCM frame transmitted by the external device. If a fault occurs to the UNI side LIU 10 having been receiving the CCM frame and switching is made so that the UNI side LIU 20 will receive the CCM frame, the reception state of the CCM frame at the UNI side LIU 20 is once made normal, and after that the reception state is monitored.</p> |
