Global mobility management: A three level architecture for next generation wireless networks

In this paper, we propose a three level global mobility model that supports IP mobility. The limitations of the existing protocols vis-a-vis their advantages in dealing with different types of mobility management schemes provide an insight to incorporate their positive features into a proposed Global Mobility Model as an extension to existing protocols. This three level model introduces a Global Mobility Agent to handle interdomain mobility. The concept is in conformation with the three level UMTS architecture and is an effort to map it to the IP mobility scenario. Simulation results, using ns-2, show that the model reduces the frequency of location updates and handover delays (especially for intradomain changes which are inevitable for mobility in large networks) with an efficient signaling mechanism. An enhanced soft handover scheme has also been proposed, which not only reduces the possibility of false handovers but also takes care of packet duplicacy and misordering.