Abstract: A communication device to be coupled to a transmission device with MC-LAG, the communication device includes a first output port coupled to an other communication device within a first route, a second output port within a second route, an iTAS device arranged in each of the first output port and the second output port, and configured to preferentially output a high priority flow, based on a set an iTAS period, a memory, and a processor coupled to the memory and configured to acquire a first iTAS period set to the iTAS device arranged in the first output port and a second iTAS period set to an iTAS device arranged in a third output port in the other communication device within the first route, and set an iTAS period of the iTAS device arranged in the second output port, based on the first and second iTAS periods.

Abstract: A communication system includes: a plurality of active paths on which a plurality of signals set with priorities are transmitted by a plurality of time-division slots; a backup path shared by the plurality of active paths; and a controller configured to control, based on the priorities, allocation of any of the plurality of signals which are allocated to any of the plurality of time-division slots and transmitted on any of the plurality of active paths, to a plurality of time-division slots on the backup path.