Research On Route Optimization And Seamless Handoff In Mobile IP

Mobile IP (MIP) based on IP layer offers a global mobility solution to support wireless Internet traffic, and it enables any mobile node (MN) to change its point of attachment to the Internet while being continually identified by its home IP address. In this paper, aiming to solve the Triangle Routing problem, minimize handoff latency and elimate the paket loss etc, the Route Optimization scheme and Seamless Handoff scheme are presented. Both these schemes are simulated by the Network Simulator. According to the simulation results, the schemes' network performances are analyzed, evaluated and validated reasonably.To eliminate the triangle routing problem and minimize handoff latency, the route optimization extensions for Mobile IP (ROMIP) is complemented and the backward smooth handoff mechanism is utilize in Network Simulator (NS-2, Version: 2). Binding cache management messages (Binding Warning, BW; Biding Update, BU; Binding Request, BR; Binding Acknowledgement, BA, etc.) are introduced into the original NS-2 framework. Moreover, backward smooth handoff mechanism is used to minimize the handoff latency. Simulation results show that, compare with the standard Mobile IP protocol: in ROMIP, the achieved bandwidth increases evidently while the end-to-end packet delay remains low. Owing to the implementation of smooth handoff, handoff latency is cut down more than 50%. Moreover, this method keeps transparent for hardware and convenient for software. Which means, it provides a valuable and practical implementation method for real-time communication in Mobile IP network.Another core part, a Seamless Handoff scheme for Mobile IP (SMIP), is presented in this paper. This novel Seamless handoff scheme is designed for large indoor open environments. It absolutely eliminates handoff latency and completely avoids packet loss by introducing a decision-making entity Control Engine (CE), redesigning the Layer 3 message mechanism for communicating entities and utilizing a handoff algorithm of pure software-based movement tracking techniques. Network Simulator is used to simulate this SMIP scheme, and the result shows that the performance in terms of latency is eliminated completely. More importantly, SMIP is capable of providing handoff between FAs without any packet loss, which means the packet loss is 0%. Moreover, throughput rate keeps in a stable status, and end-to-end delay from CH to MN is reduced to 75% compare to the standard Mobile IP in the same situation. Together these confirm the overall viability and show that the SMIP is capable of providing an effective seamless handoff in Mobile IP.