Distributed and Fixed Mobility Management Strategy for IP-based Mobile Networks

Abstract

Hierarchical Mobile IP (HMIP) reduces the signaling delay and number of registration messages to home agent (HA) by restricting them to travel up to a local gateway only. It uses centralized gateways that may disrupt the communications, in the event of a gateway failure, between a gateway and the mobile users residing with underlying foreign agents (FAs) in a regional network. Dynamic mobility management schemes, using distributed gateways, proposed in literature, tend to circumvent the problems in HMIP. These schemes employ varying regional network sizes or hierarchy levels that are dynamically selected according to call-to-mobility ratio (CMR) of individual user. In reality, this information cannot be readily available in practice. Also, any unusual alterations in CMR values may hamper the system performance. This paper proposes a new mobility management strategy for IP-based mobile networks, which is independent of individual user history. The proposed scheme uses subnet-specific registration areas and is fully distributed so that the signaling overheads are evenly shared at each FA. The scheme provides a viable alternative to dynamic mobility management schemes for its simplicity, performance, and ease of implementation.