Patent ID: 8554935

Claim:
A relay server for communicating with a first relay server connected to a first network, and functioning as a second relay server connected to a second network, the relay server comprising: a relay group information sharing unit configured to share relay group information between the first relay server and the second relay server, the relay group information indicating that the first relay server and the second relay server constitute a relay group; a relay server information sharing unit configured to share relay server information between the first relay server and the second relay server, the relay server information including activation information of the first relay server, activation information of the second relay server, activation/registration information of a client terminal connected to the first relay server, and activation/registration information of a client terminal connected to the second relay server; a routing information sharing unit configured to share routing information between the first relay server and the second relay server, the routing information including routing control points and network addresses controlled by the routing control points, the routing control points including at least two of the first relay server in the relay group, the second relay server in the relay group, the client terminal connected to the first relay server, and the client terminal connected to the second relay server; a routing group information creation unit configured to edit the routing information to create routing group information by grouping the routing control points; a routing group information sharing unit configured to share the routing group information among the first relay server, the second relay server, the client terminal connected to the first relay server, and the client terminal connected to the second relay server; a routing session establishment unit configured to establish a routing session for each group indicated in the routing group information while referring to the relay server information, the routing session enabling a communication packet to be routed via the routing control points; a routing control unit configured, when receiving a communication packet which is a routing packet, to output the communication packet if a destination network address included in the received communication packet has been registered in the routing group information; and an inter-relay server connection processing unit configured to receive the outputted communication packet and to decide a connection through which the communication packet is to be relayed based on a destination network address included in the communication packet such that the communication packet can be forwarded through the established routing session.