Simulation of multilayer Mobile IPv6 architecture in search of optimal performance

Providing mobility support in IPv6 based network is an essential requirement in order to establish IPv6 as the next generation protocol. Mobile IPv6 (MIPv6) suggests a method for mobility management, but users of MIPv6 suffers large handoff latency. So, MIPv6 is extended to Hierarchical Mobile IPv6 (HMIPv6), which reduces handoff latency and signaling overhead. HMIPv6 uses a special agent called Mobile Anchor Point (MAP) between a visitor mobile node (MN) and the home location of the MN. The function of the MAP is to co-ordinate the MN in a foreign network. Research shows that, handoff latency and signaling overhead can be further reduced by organizing MAP in multi-level hierarchical architecture. However, such hierarchical arrangement of agents increases the packet delivery cost to visitor mobile nodes resided in a foreign network. So, it is necessary to find the optimal levels of hierarchy which provides reduced handoff latency and lower signaling overhead along with an acceptable packet delivery cost. In this paper a multi-layer MIPv6 model is simulated in search of optimal hierarchy. Performance parameters handoff latency, signaling overhead and packet delivery cost are examined through simulation programs written in ns-2. Based on the results obtained it is seen that three levels of hierarchy can be considered as the optimal hierarchy with minimized cost of mobility management.