Node device and communication method for generating cluster

A node device within a network that includes a plurality of node devices, the node device comprising:

• a receiver configured to receive a packet from an adjacent node device;
• a processor configured to:
• receive a first hello packet that is a hello packet used to report route information with first information and second information being included in the first hello packet, the first information specifying a node device that belongs to a cluster that is a group of node devices each storing the route information of other node devices within the group, the second information indicating that a number of node devices included in the cluster has not reached a threshold,
• decide to join the cluster when the first information does not include device identification information for identification of the node device within the network, and
• generate a second hello packet that includes information that associates cluster identification information of the cluster and the device identification information with each other, in order to report to the adjacent node device that the node device within the network has decided to make a request for permission to join the cluster;
• and
• a transmitter configured to broadcast a hello packet generated by the processor,
• wherein, upon receipt of a third hello packet that includes third information indicating that the number of node devices included in the cluster has reached the threshold, the processor:
• starts to generate another cluster that is different from the cluster,
• generates a list to specify node devices included in another cluster, and
• generates a fourth hello packet that includes cluster identification information of the another cluster.

A node device within a network that includes a plurality of node devices, the node device comprising:

• a receiver configured to receive a packet from an adjacent node device;
• a processor configured to:
• receive a first hello packet that is a hello packet used to report route information with first information and second information being included in the first hello packet, the first information specifying a node device that belongs to a cluster that is a group of node devices each storing the route information of other node devices within the group, the second information indicating that a number of node devices included in the cluster has not reached a threshold,
• decide to join the cluster when the first information does not include device identification information for identification of the node device within the network,
• generate a second hello packet that includes information that associates cluster identification information of the cluster and the device identification information with each other, in order to report to the adjacent node device that the node device within the network has decided to make a request for permission to join the cluster, and
• a transmitter configured to broadcast a hello packet generated by the processor;
• a memory configured to hold a free node list that records device identification information of a request-making node device that is a free-node device and that has made a request for permission to join the cluster, the free-node device being a node device that does not belong to the cluster, wherein
• wherein the processor:
• when a fourth hello packet that has been received includes request-for-permission-to-join information that associates device identification information of a node device that is not recorded in the cluster list with the cluster identification information, adds the request-for-permission-to-join information to the free node list, and
• generates a fifth hello packet that includes the free node list, and
• the transmitter reports the request-making node device to the adjacent node by transmitting the fifth hello packet, and
• the processor adjusts a number of node devices to be recorded in the free node list in a manner such that a total of a number of node devices recorded in the cluster list and a number of node devices recorded in the free node list does not exceed a threshold indicating an upper limit of a number of node devices included in the first cluster.

A communication method, comprising:

• generating, by a start-point node, a cluster list that records identification information of a node device included in a cluster that includes the start-point node;
• broadcasting, by the start-point node, a first hello packet that is a hello packet used to report route information with first identification information of the cluster being included in the first hello packet,
• wherein
• upon receipt of the first hello packet, a free node that does not belong to a cluster broadcasts a second hello packet that includes route information of the free node after incorporating, into the second hello packet, a list that associates the first identification information with second identification information of the free node,
• until a number of node devices included in the first cluster reaches a threshold, the start-point node incorporates identification information of the free node recognized using the list into the cluster list, and
• storing, by a member node that belongs to the first cluster, a route to a node included in the first cluster,
• when the number of nodes included in the first cluster reaches the threshold, broadcasting, by the start-point node, a third hello packet that includes the first identification information and report information reporting that the number of nodes of the cluster has reached the threshold, and
• serving as a start point of another cluster and specifying a node device included in the another cluster, by a free node that has received the hello packet that includes the report information.