Patent ID: 8797951

Claim:
A communication system comprising a transfer node transmitting a registration request signal for requesting registration of an address of a mobile node and a server receiving the registration request signal from the transfer node, wherein when a transmission trigger for the registration request signal occurs, the transfer node determines the type of the transmission trigger, and depending on the determined type, determines whether or not the number of mobile nodes which will be registered or which will have a registration expiry time postponed are a plurality, in accordance with the registration request signal, wherein if the plurality of mobile nodes are not to be processed, the transfer node generates and outputs a registration request signal intended for one mobile node, to the server, and if the plurality of mobile nodes are to be processed, the transfer node generates and transmits, to the server, a piece of information indicating that the plurality of mobile nodes will be processed, or a piece of information indicating the plurality of mobile nodes which will be processed, or an aggregation registration request signal with both pieces of information, and wherein upon receiving the registration request signal from the transfer node, the server executes a process of registering the mobile node specified in the registration request signal or of postponing the registration expiry time for the mobile node, and upon receiving the aggregation registration request signal, the server executes a process of registering the specified plurality of mobile nodes or of postponing the registration expiry time for the specified plurality of mobile nodes, and wherein upon receiving the registration request signal from the mobile node, the transfer node determines whether or not the registration request signal is to be an aggregation target, depending on the type of the registration request signal, and if a determination result indicates that the registration request signal is not to be an aggregation target, the transfer node transmits the registration request signal to the server, and if the determination result indicates that the registration request signal is to be an aggregation target, the transfer node holds the registration request signal until a predetermined time, aggregates held registration request signals to generate the aggregation registration request signal, and transmits the aggregation registration request signal to the server at the predetermined time.