Patent ID: 8672566

Claim:
A first node apparatus in a network including a plurality of node apparatuses including the first node apparatus and a second node apparatus that are connected in a wired manner, the first node apparatus comprising: a plurality of ports, each of which is a port to connect, in the wired manner, the first node apparatus to another different node apparatus other than the first node apparatus among the plurality of node apparatuses; a storage device that stores: loop detection information that associates, with first identification information for identifying a first frame, destination port distinguishing information for distinguishing, from among the plurality of ports, a first port that has been used as a destination port when the first node apparatus has transmitted the first frame, and routing information that associates, with each of one or more of the plurality of node apparatuses, state information for indicating whether frame transmission from each of the plurality of ports is feasible or not; a receiving circuit that is connected to the plurality of ports, and that receives a second frame from the second node apparatus, the second frame including second identification information for identifying the second frame; an updating circuit that updates, when the second identification information is identical with the first identification information, the state information associated by the routing information with a destination node apparatus that is one of the plurality of node apparatuses and that is a destination of the second frame to make the updated state information indicate that frame transmission from the first port is not feasible; and a transmitting circuit that is connected to the plurality of ports, that selects a second port from which transmission of the second frame is feasible from among the plurality of ports, according to the state information associated by the routing information with the destination node apparatus, and that transmits the second frame from the second port.