Patent ID: 7072314

Claim:
A method comprising: establishing a communication path between a mobile-device in a first-communication-area and a server through a home-agent, the mobile-device initially assigned a set of addresses when registered with the home-agent including a first real-address and a first home-address, with the home-agent using the assigned addresses to track the mobile-device, wherein establishing the free communication path further comprises: generating a request from the mobile device, the request comprising a request-layer including the first home-address of the mobile device and a server-address of the server; encapsulating the request-layer with a roaming-layer including the first real-address of the mobile-device and a home-agent-address; communicating the encapsulated request-layer to the home-agent; maintaining the communication path through the home-agent when the mobile-device moves to a second-communication-area, with the mobile-device requesting a new address from an address server and communicating the new address to the home-agent; and using respective program layers below transmission control protocol/internet protocol (TCP/IP) program layers in the mobile-device and the home agent to establish the communication path and maintain the communication path.