Managing Heterogeneous Access Networks Coordinated policy based decision engines for mobility management

Next generation networks will consist of heterogeneous access networks and will provide a variety of services. In such an environment the question of the assignment of terminals to access networks and mobility management becomes a challenging problem. This is especially true when one takes the user goals and network operator goals into account. Users would like to be connected to their services over the best available access technology, where the users should be able to define what "best" means for themselves, in other terms users want to be Always-Best-Connected (ABC). The network operator has to satisfy ABC property for users who are essentially competing for resources and has to maintain the best possible utility out of its investment. This can be coined as Always-Best-Managed (ABM) networks. Taking into account that what best means for different users will be different in practice that it will not be possible to fulfill the requirements of each of the users simultaneously, and that the network itself is dynamic in nature, one can imagine the difficulty of achieving ABC and ABM continuously and simultaneously. In this paper we introduce a new approach to policy based mobility management based on two coordinated decision engines, one residing in the terminal and one in the network. We describe our architecture enabling network controlled policy based mobility management and discuss first results observed with our prototype implementation of this architecture.