Patent ID: 8184659

Claim:
A telecommunications network system comprising: a user terminal working under a first version of Internet protocol (IP); a server placed on a first IP network working under the first version; a second IP network working under a second version of the Internet protocol to be communicable with said user terminal and said server; a first translator for connecting said user terminal to said second IP network; a second translator for connecting said server to said second IP network; and a prefix management server placed on said second IP network, and being configured to store and manage both a first prefix for a first address of the user terminal and a second prefix for a first address of the server for converting the first addresses to the second version thereof, for respective links between the user terminal and the first IP network to be connected in association with each other, the first prefix being developed for the user terminal and being assignable to said first translator to which said user terminal is connected for translating the first address of the user terminal to the second version thereof, and the second prefix being developed for the first IP network and being assignable to said second translator to which said first IP network is connected for translating the first address of the server to the second version thereof, said first translator comprising a first converter for attaching the first prefix obtained from said prefix management server to the first address of said user terminal, when acting as a sender, the first address being contained in a first packet of the first version received from said user terminal, and attaching the second prefix obtained from said prefix management server to the first address of said server, when acting as a destination, to thereby convert the first packet to a second packet of the second version, said second translator comprising a second converter for analyzing the second packet received from said first translator to identify the first address corresponding to said first IP network from the second prefix contained in the second packet, and specifying the identified first address as a sender address contained in the first packet to be sent to said server to thereby convert the second packet to the first packet.