Patent ID: 7346039

Claim:
A communication system comprising a wireless terminal, a plurality of Internet Service Providers (ISPs, each ISP managing at least one terminal-side network, two or more terminal-side networks communicating with said wireless terminal, and a backbone-side network managed by an ISP different from the ISPs managing the terminal-side networks and connected to said terminal-side networks and connecting said wireless terminal with a backbone network, the wireless terminal traveling between said terminal-side networks during communication, wherein each of said terminal-side networks has a relay device for relaying communication between said wireless communication terminal and said backbone-side network, and wherein said backbone-side network has a position management device for managing positional information of said wireless terminal and an authentication device for authenticating said wireless terminal according to contract information of said wireless terminal, wherein each of said terminal-side networks has an authentication data relay device for relaying authentication data in which said wireless terminal requests an authentication from said authentication device, wherein said relay device has an identification-information correspondence information generation device for generating correspondence information between identification information of a network to which said wireless terminal belongs and identification information of said position management device, and wherein said identification-information correspondence information generation device extracts the identification information of the network to which said wireless terminal belongs and the identification information of said position management device from the information transmitted from said position management device to said wireless terminal to generate said identification-information correspondence information, and a path control device for controlling a path of a packet in packet communication of said wireless terminal so that the packet transmitted by said wireless terminal passes through said position management device by referring to said identification-information correspondence information.