Abstract: A route computing system is capable of computing routes at a high speed at a low cost without the need for replacing the hardware of a transmission device. The transmission device has a destination information receiving unit for receiving destination information indicative of the destination of a packet from a terminal device. The transmission device also has a destination information storing unit for storing the destination information, and a routing packet sending unit for receiving a routing protocol packet from another transmission device and sending the routing protocol packet to the terminal device. The terminal device has a routing packet receiving unit for receiving the routing protocol packet sent from the routing packet sending unit. The terminal device also has a computing unit for recomputing the destination information based on the routing protocol packet, and a destination information sending unit for sending the recomputed destination information to the destination information receiving unit.

Abstract: Respective nodes on an MPLS network includes a priority path management section that manages a label, which has been advertised by a neighboring node on a priority path, is designated as a priority transmission label, and is paired with a label advertised by the node itself, a detour path management section that manages a label, which has been advertised by a neighboring node on a detour path, is designated as a detour transmission label, and is paired with a label advertised by the node itself, a failure detection section that detects a failure between the node itself and a neighboring node, and a path switching section that, if a failure is detected, replaces a label attached to data to be forwarded to the neighboring node on the priority path with the detour transmission label instead of the priority transmission label, and forwards the data to the neighboring node on the detour path.

Abstract: A route computing system is capable of computing routes at a high speed at a low cost without the need for replacing the hardware of a transmission device. The transmission device has a destination information receiving unit for receiving destination information indicative of the destination of a packet from a terminal device. The transmission device also has a destination information storing unit for storing the destination information, and a routing packet sending unit for receiving a routing protocol packet from another transmission device and sending the routing protocol packet to the terminal device. The terminal device has a routing packet receiving unit for receiving the routing protocol packet sent from the routing packet sending unit. The terminal device also has a computing unit for recomputing the destination information based on the routing protocol packet, and a destination information sending unit for sending the recomputed destination information to the destination information receiving unit.