SIMULATION STUDY OF TCP PERFORMANCE OVER MOBILE IPv4 AND MOBILE IPv6

Abstract: Mobile IPv6 (MIPv6) is a protocol to deal with mobility for the next generation Internet (IPv6). However, the performance of MIPv6 has not yet been extensively investigated. Knowledge of how MIPv6 affects TCP performance, especially in comparison with MIPv4, can provide directions for further improvement. In this report, an intensive simulation study of TCP performance over MIPv4 and MIPv6 has been conducted. Sim-ulation using the famous network simulator NS-2 will be used to highlight differences when TCP is used in hybrid wireless environment, over these two Mobile IP protocols. Initial simulation has shown a solid im-provement in performance for MIPv6 when IPv6 Route Optimisation features are used. During the course of simulation, a consistent event causing dropped TCP throughput was identied. Out of order arrival of packets would occur when the mobile node initiated a handover. This out of order arrival invokes TCP congestion control falsely which reduces throughput. The difference in overall throughput of MIPv4 compared to MIPv6 is roughly proportional to the difference in packet size attributed to IPv6's increased header size. Another contribution of this work is to provide modications and new functions such as node processing time, to the NS-2 simulator to make such investigation possible. To the best of our knowledge, no similar publication has been reported.