Patent ID: 7355967

Claim:
A transmission device performing transmission control on a ring network comprising: a setting information relay unit relaying setting information that sets a specific channel as a non-preemptible channel restricted from being used for restoration; a channel establishment unit determining, by referring to the setting information, whether a channel of interest should be set as said non-preemptible channel and establishing the channel; and a route switch control unit recognizing a section in which said non-preemptible channel that is not used for restoration has been established and a fault bypass control condition at the time of occurrence of a fault and performing a route switching control based on a result of recognition, wherein: the setting information includes NUT (non-preemptible unprotected traffic) table information that contains a start transmission device ID (identification) and an end transmission device ID) that indicate a section in which said non-preemptible channel should be established, a type of setting for setting said non-preemptible channel, and a relay direction; and said channel establishment unit recognizes and establishes said non-preemptible channel via a designated write address in which the NUT table information should be written.