Patent ID: 7529182

Claim:
A communication method for a network where a plurality of communication devices are interconnected and a plurality of pairs of working channels and backup channels are set in two paths between adjacent communication devices to perform 1:1-protection communications, said communication method comprising the steps of: performing said 1:1-protection communications by switching from working channels set in one of said two paths to corresponding backup channels set in the other of said two paths based on the location of a detected failure; wherein for first information traffic of a type where importance determined by the type of information to be transmitted is relatively high, said communication devices perform said 1:1-protection communications to set channel in use to a first working channel set in one of said two paths when there is no failure, and to set channel in use to said corresponding backup channel set in the other of said two paths based on the location of the detected failure when the failure is detected; and for second information traffic of a type where said importance is relatively low, said communication devices perform communications to set channels in use to a second working channel other than said first working channel, in one of said two paths and to at least said backup channel for said second working channel when there is no failure, while said communication devices perform a routing process to change said channel in use from said backup channel for said second working channel to said second working channel, and perform communications, for said second information traffic having set channel in use to said second working channel and having changed channel in use to said second working channel, to set channels in use to said backup channel for said second working channel by said switching for said 1:1-protection communications, based on the location of the failure, when the failure is detected.