Communication system, multicast-capable router, transmitter terminal, receiver terminal, and communication method

摘要

A communication system ( 1 ) is provided with URs ( 20 a to 20h) and a source terminal ( 10 ). The URs ( 20 a to 20 h) include: entry holders ( 21 a to 21 h) for holding forwarding addresses; message processors ( 25 ) for registering the addresses of other URs, the addresses being associated with a source terminal address and a multicast group address, in the entry holders ( 21 a to 21 h) as the forwarding addresses; message providers ( 26 ) for providing the source terminal address with join request messages which request the addition of the addresses of the URs to sending addresses. The source terminal ( 10 ) includes: an entry holder ( 11 ) for holding a sending address; and a message processor 14 for registering the addresses of the URs ( 20 a to 20 h) in the entry holder 11 as sending addresses based on the join request messages.