Patent ID: 7305010
Filing Date: 2007-12-04
Classification: H04L

Abstract:
1. In a multicast communication system having a routing device connected to a network and one or more client hosts connected to the network through this routing device, and in which each one of the one or more client hosts includes request means for transmitting a multicast control packet for requesting joining or leaving a multicast group, to the routing device, and the routing device includes delivery means for receiving multicast data to which a specific address is assigned for each multicast group, and delivering it to client hosts participating in that multicast group, the multicast communication system characterized in that the routing device includes means for notifying a client host by using a network layer protocol, by adding an information indicating an accounting start to a multicast control packet, when multicast data to be delivered is accounting target and the client host starts to receive the multicast data that are accounting target, and each one of the one or more client hosts includes means for recognizing an accounting start from the multicast control packet by using the network layer protocol.