A communication apparatus operates as a node of a network. The communication apparatus includes a port-state managing unit that updates, every time failure occurrence in the network is detected, state information indicating a state of the network, a database updating unit that updates, based on a transmission source address and a reception port of a received frame and the state information managed by the port-state managing unit, a database that determines an output port when a frame in which the transmission source address is a destination address is received, and an output-destination determining unit that determines an output port of the received frame by searching through the database using, as search keys, the destination address of the received frame and the state information managed by the port-state managing unit.