US Patent 9391694 Protection path providing method and transmission device

A protection path providing method is used in a network that includes a shared section in which a first protection path corresponding to a first work path to transmit a first traffic and a second protection path corresponding to a second work path to transmit a second traffic are configured. The method includes: transmitting a message that includes information indicating a transmission rate of the first work path via a logical ring, the logical ring being formed using a route for which the first work path is configured and a route for which the first protection path is configured, when a failure is detected in the first work path; and controlling a switch circuit installed in a transmission device provided at an end of the shared section in accordance with the message in such a manner as to transmit the first traffic via the shared section.