Patent ID: 8654678

Claim:
A node device included in an information communication system which comprises a plurality of node devices capable of performing communication with each other via a network, the node device comprising: a processor, a memory configured to store a program to be executed by the processor, and a first storing unit, which is volatile, that stores link information used for performing communication with another node device, the link information including node information indicative of at least one specific node device; wherein the processor is configured to execute the program to: cause the link information stored in the first storing unit to be stored in a second storing unit, which is nonvolatile, at a predetermined timing, while the node device is participating in the information communication system; cause the link information stored in the second storing unit to be stored in the first storing unit, in response to participating in the information communication system again after withdrawing from the information communication system; determine if any of the node information out of the node information included in the link information is stored in the first storing unit by the processor; transmit participation notification for notifying the node device of the node information on the basis of the determined node information; determine whether transmission of the participation notification succeeded or not; and determine whether another node information is still included in the link information stored in the first storing unit by the processor or not in response to determining that transmission of the participation notification fails, wherein in the case where it is determined that the other node information is still included in the link information stored in the first storing unit, the processor transmits the participation notification to the node device corresponding to the other node information included in the link information stored in the first storing unit, and wherein when it is determined that there is no other node information in the link information stored in the first storing unit, the processor transmits the participation notification to a participation management node device for managing participation to the information communication system, which is another node device included in the information communication system, the processor receives from the participation management node device, the link information including the node information of at least one or more node devices included in the information communication system, and the processor stores link information received from the participation management node device in the first storing unit.