Patent ID: 8305934

Claim:
A non-transitory computer-readable medium encoded with a network management program for managing a plurality of communication devices which forward packets based on forwarding data describing associations between destination addresses and output ports, the network management program, when executed by a computer, causing the computer to execute a procedure comprising: changing original routes, which have been determined from forwarding data of the communication devices, to new routes in response to an event that influences existing forwarding routes of packets; identifying a destination-reachable range from which packets can reach a destination information processing device specified by a destination address, by extracting partial routes that include at least a communication device adjacent to the destination information processing device and belong to both the original routes before update and the new routes after update; identifying a destination-unreachable range from which no packets can reach the destination information processing device, by excluding the identified destination-reachable range from the original routes; modifying output port parameters in the forwarding data of a neighbor communication device which is located in the destination-unreachable range and adjacent to one of the communication devices in the destination-reachable range, so as to permit forwarding of packets from the neighbor communication device to said one of the communication devices in the destination-reachable range; transmitting the modified forwarding data to the neighbor communication device; and adding to the destination-reachable range an additional destination-reachable range which has become capable of reaching the destination information processing device as a result of the modification of the forwarding data.