Patent ID: 8798054

Claim:
An IP network system wherein packet communication is executed between respective hosts through an intermediary of a ring network comprised of at least a plurality of repeaters, the respective repeaters comprising: an arithmetic and control unit for transferring a packet to a host at a transmission destination via a clockwise route, and a counterclockwise route, in the ring network, respectively, on the basis of transfer direction information contained in a tunneling packet generated on the basis of a transmitted packet transmitted from a host at a transmission source, as one of the respective hosts, to the host at the transmission destination, and subjected to multicast transmission to a multicast address where the host at the transmission destination belongs, wherein each repeater comprises: a memory for storing the multicast address where the host at the transmission destination belongs, and network addresses of other of the plurality of repeaters connected to the repeater itself, and at least any of the respective hosts; and a communication unit for executing packet communication with the respective hosts, and other repeaters, and receiving the transmitted packet transmitted from the host at the transmission source to the host at the transmission destination; wherein the arithmetic and control unit is for applying encapsulation processing to the transmitted packet, thereby generating and duplicating a tunneling packet while adding transfer direction information to the tunneling packet before effecting multicast transmission to the multicast address, and transmitting the tunneling packet in the clockwise direction, and the counterclockwise direction, in the ring network, respectively, on the basis of the transfer direction information, upon receiving the tunneling packet via the communication unit, or if a host belonging to a destination group of the tunneling packet as received is connected to the repeater itself, reproducing the transmitted packet before application of the encapsulation processing, thereby transferring the transmitted packet to the host at the transmission destination.