Patent ID: 7450546

Claim:
A method of managing mobility of a plurality of mobile nodes between heterogeneous networks in an Internet Protocol (IP) based mobile communication system including a plurality of access nodes for providing an IP service to mobile nodes located in their service areas and a server for supporting connection to the access nodes by the mobile nodes, the method comprising the steps of: classifying the access nodes according to an available service level; generating service level contexts, each containing of access nodes (ANs) having the same service level; performing a handoff using a context corresponding to a service level required by a mobile node during movement of the mobile node between the networks; and updating the service level contexts when at least one of the access nodes experiences a change in the service level, wherein the service level context updating step further comprises the steps of: informing the server of the change through a service level change message sent by the access node that experienced the change in service level; and removing, by the server, a corresponding access node from a service level context for a previous service level and adding the corresponding access node to a new service level context according to the service level change message.