Performance analysis on hierarchical Mobile IPv6 with fast-handoff over end-to-end TCP

Mobile IPv4 has been considered as the de facto standard in providing Internet mobility. However, as the demand for wireless mobile devices capable of executing real-time applications increases, it is necessary to provide superior handoff latency and quality of service (QoS). Mobile IPv6 is designed to resolve these issues, and has numerous applicable optimization techniques. Two ways of reducing the handoff latency, in both IPv4 and IPv6, have been proposed in the literature. One aims to reduce the (home) network registration time while the other aims to reduce the lengthy address resolution time when in a visiting network. We present a performance analysis of the current IETF proposals, namely, the hierarchical Mobile IPv6 architecture and the fast-handoff mechanism. The former is aimed at reducing the registration time while the later in reducing the address resolution time. We show through simulation that managing the registration process in a hierarchical fashion greatly reduces the overall handoff latency. Comparatively, the fast-handoff mechanism is even more capable of reducing the handoff latency. The simple superimposition of these two frameworks produces the best overall handoff latency result. However, the overall improvement is not a simple aggregation of the individual handoff latency gains. In fact, we discovered some rather non-trivial traffic behavior when these two frameworks are combined. We identify the causes which hinder the handoff performance and hence devise a set of design guidelines to improve the handoff latency further.