Setting of a bypass path upon occurrence of transmission failure, is applicable for large scale network. A system includes signaling means which makes judgment whether bypassing process is performed by an own node by a bypassing process judgement means when a release message issued upon occurrence of failure, is received. Upon judgment to perform bypassing process, computation of bypass path is requested by the path computing means. On the basis of result of computation, bypass path is established and switched. In the bypassing process judgment means, judgment is made whether bypassing process is performed by the signaling means or not depending upon the relationship of positions of the faulty portion and the own node.