Patent ID: 7577119

Claim:
A data communication method for a mobile network including a destination foreign agent and a plurality of other foreign agents connected to each other through a high-speed transfer network and in which data transferred to a mobile node from a home agent is transferred to the mobile node through the destination foreign agent and a wireless base station in the destination foreign agent, each of the foreign agents includes a binding list which is adapted to control a correspondence between MAC addresses and IP addresses of mobile nodes, comprising: establishing wireless connection between the mobile node and the destination foreign agent, and the destination foreign agent recognizes the MAC address of the mobile node; the destination foreign agent registering the MAC address of the mobile node in a MAC address field of a handoff request message including the MAC address field and an IP address field; the destination foreign agent feeding the handoff request message onto the transfer network where the destination foreign agent and the plurality of other foreign agents are connected to one another; each of the plurality of other foreign agents receiving the handoff request message, and judging whether the MAC address corresponds to an IP address of the mobile node in a binding list of the foreign agent itself; registering, by other foreign agents having the MAC address and an IP address which corresponds to the MAC address in the binding list of the foreign agents themselves, the IP address in the IP address field of the received handoff request message; the other foreign agents having the MAC address and the IP address which corresponds to the MAC address in the binding list feeding the handoff request message onto the transfer network; the destination foreign agent receiving the handoff request message, and registering the MAC address and the IP address in the binding list; the destination foreign agent identifying data sent from the home agent to the mobile node on the transfer network, based on the information which has been registered in the binding list; and the destination foreign agent transferring the identified data to the mobile node.