Patent ID: 8009683

Claim:
An IP network system comprising: a plurality of relays making up a ring network; a source host for transmitting a packet and connected to the ring network; and a destination host which conducts a packet communication with the source host through the ring network, wherein each of the relays is operable to transfer received packets containing a transfer direction information to the destination host through a right-handed route of the ring network and through a left-handed route of the ring network, based on the transfer direction information, further comprising: a plurality of tunneling units connected to the ring network, the tunneling units comprising: a source tunneling unit connected to the source host; and a destination tunneling unit connected to the destination host, wherein the source tunneling unit is operable to: a) perform capsulation on a packet from the source host to generate a tunnel packet; b) copy the tunnel packet to generate a copy tunnel packet; c) add the transfer direction information to the copy tunnel packet and the tunnel packet; and d) transmit the tunnel packet and the copy tunnel packet to which the transfer direction information is added, to the right-handed route and the left-handed route of the ring network, wherein each of the tunneling units comprises: a communication section for conducting the packet communication; a storage section for storing at least one network address of the relays connected to the tunneling unit and the source and destination hosts; and a computation control section, wherein the computation control section is operable to: a) perform the capsulation on the packet from the source host to generate the tunnel packet; b) copy the tunnel packet to generate a copy tunnel packet; c) add the transfer direction information and a network address of a destination relay to the copy tunnel packet and the tunnel packet; d) control the communication section to transfer the copy tunnel packet and the tunnel packet to the destination tunneling unit through any route of the ring network; e) perform decapsulation on the tunnel packet received by the destination tunneling to reproduce the packet before subjected to the capsulation; f) control the communication section to transfer the reproduced packet to the destination host based on information about the destination host contained in the reproduced packet; and g) store the reproduced packet in the storage section.