| 摘要 |
<p>PROBLEM TO BE SOLVED: To obtain a packet relay device enabling packet relay by using a wide-area public line as a diversion route, when a network is separated due to the occurrence of failures between terminals at a plurality of points in a layer-2 ring network causing disabled communication.SOLUTION: The packet relay device includes: means 13 for detecting the occurrence of a fault in the ring network to which the self-relay device is connected, and for acquiring the IP address of a terminal reachable from the self-relay device through a layer 2; means 15 for notifying a layer-3 device of routing information to the terminal reachable by the layer 2, using an RIP packet; means 16 for responding to an ARP request from the terminal reachable by the layer 2, as a proxy for the layer-3 device; and means 14 for updating an ARP table of the terminal reachable by the layer 2.</p> |
