A Research On Mobile IPv6 Network Performance

Wireless Access will gradually become the primary Internet access method alongwith the further development of Internet services and the increase of the usage ofmobile phones, PDAs and laptops. Once the subscribers have broken away from thewire, they hope to use fixed accounts and networking configurations to connect to theInternet anywhere through arbitrary access modes (wired or wireless). And it is alsoexpected that network applications will not be interrupted during the node's movementand always keep online. Mobile IP was born to meet this need and its goal is to enablethe node to switch between different subnets while keeping a fixed IP address andmaintaining transparent to up-layer applications as well as down-layer physical links.As a network technology on the cutting edge, Mobile IPv6 has an extensiveapplication prospect and enormous commercial value. However, before pushed intopractical application, it has several aspects to be improved among which theperformance optimization is the current researching hotspot. It is far from enough tostudy the performance from the protocol itself and the most intuitionistic andconvincing way is experiment. In this research, we used NS-2, a discrete eventsimulator for network research, to set up a fairly complicated WLAN-based MobileIPv6 experiment environment. We observed network performance parameters such asinstantaneous bandwidth, handoff latency, packet loss, end-to-end delay, channelthroughput and signaling load from the viewpoints of a single node and the wholenetwork respectively. The rules and related reasons of their variety were also analyzedand a policy of route optimization was advanced. Through the experiments and analyses,we discovered the "double bandwidth"phenomenon after a node's handoff and got theformulas of handoff latency and packet loss and made the following conclusions: 1)Packet loss has relation with not only the handoff latency, but also the handoff type(from home link to foreign link or from foreign link to foreign link). 2) Routeoptimization may lead to a higher handoff latency and packet loss. 3) The up-layertraffic may have impact on the handoff behavior of the mobile node. 4) The signalingload of Mobile IPv6 will not impropriate too much network bandwidth generally.