Research On Mobile IP Handoff

In recent years, the applications of remote office and mobile computing keep increasing, and in wireless environment, the Mobile Host must adopt handoff technology to keep the connections when it moves between different sub networks. In order to provide better service, we should study the mobile IP handoff technology further. The mobile IP handoff technology has been the key factor to both the wireless communications system and the wire communications system .And what's more, the studies on the Mobile IP handoff - technology has become one of the important researching fields of the computer network.Mobile IP has provided IP mobility solution and made it possible for mobile node to changeits point of attachment without losing its ability to communicate and use a permanent IP toaccess any link.In order to set forth the Mobile IP handoff - technology, firstly, the paper makes analysis in depth of the Mobile IP handoff scheme. And it's pointed out that the handoff latency is the main section of the latency of the motion detection, which is caused by the fact that the host has to passively perform the motion detection. The adaptive initiative predictive algorism could be adopted to predict the network conditions and the movement of the Mobile Host, which leads to advance the efficiency of the mobile IP handoff.Afterward, both the Mobile IP handoff motion detection scheme and its different methods are introduced. The interaction processes of receiving and affording the register messages between the host and the agents are explained in detail. Meanwhile, both the Mobile IPv6 and the Mobile IPv4 architectrue and their handoff schemes are discussed and the existing problems are analyzed.The paper classifies various fast handoff shcemes into hierarchical mobility management scheme, Celluar IP, HAWAII, the handoff scheme combined with information ofdata link layer etc.After that, every scheme isdiscussed respectively.Considering about the influence of wireless link to TCP performance, the dissertation discusses the features of wireless link, compares three different mechanisms which proposed to enhance TCP performance in wireless networks. On these comparisons, it is recommendded that using Snoop technique to improve TCP performance in the process of mobile IP handoff could have more merits in some way.On the base of research different schemes which ameliorated to advance the mobile IP handoff efficiency, a new scheme Link-Layer-Info.-Pre-Registration District Handoff Project, which Based on the theory of Pre-registration mapped onto District-Switch-Project is presented. Then, it is discussed how to realize the new project in detail.In addition, another new mobile IP data transmission protocol is put forward to solve the triangle router problem, which comes forth when the standard mobile IP protocol is used to transmit data between mobile IP hosts.Eventually, an OPNET emulational experiment is done to test the capability of the new project LLIPRDHP. The result shows the new project has strongpoints such as fast handoff, low data losing ratio, low error bits ratio etc.