Enhanced cross-network handoff for mobile ip service mobility

Abstract

A system and method are described whereby an enhanced handoff scheme provides for monitoring of mobile device conditions and network conditions associated with a current access network attachment, as well as with a plurality of access networks on a preferred access network list, to proactively initiate a handoff operation, thereby preserving the QoS constraints necessary for seamless delivery of IP multimedia services. In an embodiment, each of the plurality of access networks is connected to an IMS core network, whereby a policy function receives quality of service constraints associated with the launched application from the mobile device and orders a list of preferred access networks accordingly. Preferably, the policy function selects an appropriate access gateway associated with a target access network based at least in part on the mobile device conditions reported by the mobile device and the access network conditions monitored by the policy function.