PROACTIVE HANDOVER SCHEME FOR NODES IN MOBILE IP NETWORK

Abstract

Mobile IP, the IETF proposal for IP mobility support, represents a key element for future All-IP wireless networks to provide service continuity while on the move within a multi-access environment. Handoff latency in Mobile IP results in packet losses and severe performance degradation for delay sensitive real-time applications, such as audio streaming. In order to mitigate these effects, various Mobile IP extensions have been proposed to augment the base Mobile IP with hierarchical registration management, address pre-fetching and local re-transmission mechanism, namely, Cellular IP, Hierarchical Mobile IP, Hierarchical Mobile IP with Fast-handover, Hawaii. We propose a Location-aware improvement over a fast and seamless handoff for Hierarchical Mobile IP. In this report we have proposed a handover scheme that applies location information available to the mobile nodes and access points in proactively discovering the next agent/access point and hence gain more control over the actual handoff latency and buffering requirements. Mobile node movement tracking has been implemented to examine the effect of linear and ping-pong movement on handoff latency. Also, we have performed a simulative evaluation of our proposed scheme to compare it with other Mobile IP based mobility protocols i.e. Cellular IP, Hawaii, Hierarchical Mobile IP. The study provides the quantitative results of these protocols with respect to hand off latency, packet-loss rate and buffering requirements. The proposed handover scheme has been implemented as extensions to Network simulator version 2 (ns-2). The simulation is written in TCL & C++ and runs under LINUX on a Pentium 4 machine.