Patent ID: 7664878

Claim:
A communication system including a mobile terminal, a relay apparatus which offers an access link to the mobile terminal, and a layer 2 switch which relays data between the relay apparatus and a router on a next hop from a communication destination terminal of the mobile terminal, wherein the mobile terminal comprises a route information notification unit which notifies, to the relay apparatus and the layer 2 switch in a subnet where the mobile terminal is present, route information including a data link layer unicast address of a packet addressed to the mobile terminal, and a data link layer multicast address of the mobile terminal in a case where the mobile terminal is activated and in a case where the mobile terminal switches a connection destination relay apparatus, the route information is used by the relay apparatus and the layer 2 switch to update bridge forwarding tables (BFTs) owned thereby, and the BFTs store the data link layer unicast address, the data link layer multicast address and a port from which the route information is received, while associating the data link layer unicast address, the data link layer multicast address and the port.