Patent ID: 7035226

Claim:
A path setup device for setting up a label switched path in a label switching network including a plurality of routers, comprising: a decision device, when a label request is received, deciding whether there exists a label switched path which has already been set up and which corresponds to a path requested in the label request; a label allocation device, when the set-up label switched path exists, allocating another label, for the label request, which is the same as a label of the set-up label switched path; a different-label allocation device, when a request to release the another label is received from a router notified of said another label, performing processing for allocating a label different from the label of the set-up label switched path for the label request requesting a path corresponding to the set-up label switched path; and a path learning device automatically learning a path that cannot be allocated with a same label and prohibiting allocation of said same label for the learned paths wherein when a request to release said same label has been received, the different-label allocation device notifies the pat learning device of the path and the path learning device learns the notified path as a path that cannot be allocated same label.