Patent ID: 7075897

Claim:
A wireless communication system comprising multiple terminals each of which terminals has a unique terminal identifier to be identified from any other terminal on the network, wherein each respective of said multiple terminals comprises: a terminal identification means for identifying any other terminal with which the respective one of the terminals communicates using the terminal identifier of the other terminal; a duplication notification means that operates when the respective terminal detects the existence of another terminal having the same terminal identifier as the respective terminal to issue notification of that duplication of terminal identifiers to the another terminal; a substitute notification means which operates when the respective terminal detects that plural other terminals to which the respective terminal can communicate have the same terminal identifier, but different from the terminal identifier of the respective terminal, to notify the duplication of the same terminal identifier to at least one of said plural other terminals wherein the network on which said multiple terminals are connected is an IP (Internet Protocol) network utilizing IP addresses for terminal identifiers and, wherein said terminal identification means provides an address coordination table that, for a specified time, holds the coordination between the IP address of each other terminal on said IP network and a physical identifier unique to each said other terminal and provides a registration means that operates when a sender and IP address of a duplication notification packet received by the respective terminal from any other terminal is different from the IP address of the respective terminal, moreover said sender IP address is not registered in said address coordination table, to register said sender IP address and the physical identifier of the terminal that is said sender in said address coordination table.