COMMUNICATION CONTROL PROGRAM

PROBLEM TO BE SOLVED: To reduce cost for securing a detour, to prevent the consumption of resources of a routing table, and to stabilize a network in a short time. SOLUTION: In a system including a router, routers #a-#d are communicably connected to each other to constitute the network. Then, an L2 switch #a to which a server is connected, an L2 switch #c to which a client #a is connected and an L2 switch #b for connecting the L2 switch #a to the L2 switch #c are connected between the routers #a and #b to constitute a sub-network in the network in this system. In such a configuration, the router #b detects a failure occurring in the sub-network, decides the detour for securing communication between a device connected to the sub-network segmented by the detected failure and other network and to establish tunneling which is a virtual directly connected communication circuit. COPYRIGHT: (C)2008,JPO&INPIT