IP PACKET TRANSFER DEVICE

摘要

PROBLEM TO BE SOLVED: To recover a fault at high speed and to prevent abrupt drop in QoS by providing a routing table used on the occurrence of a fault in addition to a conventional routing table which is used for transferring IP packets. SOLUTION: This device provided with an immediate recovery routing table 9 that records router information different from router information recorded on a routing table 7 corresponding to a destination. Plural immediate recovery routing tables 9 which correspond to points at which the occurrence of a fault is assumed. A routing control section 5 applies routing to an IP packet according to the immediate recovery routing table 9, corresponding to the fault occurrence point on the occurrence of a fault. Conventional or highly reliable classes are placed on each IP packet according to the importance. On the occurrence of a fault, a packet discrimination section 10 applies routing to an IP packet of a conventional class according to the routing table 7 and applies routing to an IP packet of a highly reliable class according to the immediate recovery routing table 9.