Patent ID: 7715423

Claim:
A communication terminal device for performing communication based on a communication protocol defined so that first identification information assigned to the communication terminal device is transmitted to and received from a plurality of communication parties, the communication terminal device comprising: identification information generating means which, based on information unique to the communication terminal device, generates second identification information different from the first identification information; storage means which stores a table containing data linking the second identification information generated by said identification information generating means with a type identifier of the communication terminal device, and for storing data linking device identification information with type identifiers received from the plurality of communication parties; control means which controls said storage means so that communication with the plurality of communication parties is established based on the table, wherein said control means broadcasts the second identification information and type of the communication terminal device to the plurality of communication parties, and updates the table based on device identification information and a type identifier corresponding to each of the plurality of communication parties which are sent back as a response to the broadcast, the control means rebroadcasting the second identification information and the type of the communication terminal device according to a count value controlled by a clock of the device until the count value exceeds a predetermined threshold; and detection means for detecting an operating instruction supplied from an external network or a user interface, wherein the communication terminal device, upon detecting the operating instruction, generates and broadcasts a command corresponding to the operating instruction, along with the device identification information and the type identifier, to the plurality of communication parties to determine a communication party that matches the device identification information and the type identifier, the communication party that matches the device identification information executing processing according to the operating instruction.