The Research On Key Techniques Of Mobile Network And NEMO Routing Optimization

In recent years more and more attention is paid to the research and application of network mobility management. The key techniques involved include mobility management, location management, handover management, route optimization, safety mechanism, flow distribution and so on. The NEMO protocol proposed and based on MIPv6, not only ensures the continuity of communication when subnet moves, but also makes mobility transparent to the node within subnet. The NEMO applications will adapt better to the development requirements of the next generation mobile communication network.This thesis summarizes the latest achievements in the research of management of network mobility, and analyzes in-depth the issues on the characteristics, working principles, protocols and implementations of NEMO, and focuses mainly on the routing optimization, handover management, NEMO internal route protocol, and proposes the NRO and HRO routing optimization solutions.This thesis firstly introduces the MIPv6 and NEMO techniques, and indicates the key research points of mobile network. Then it analyzes the existing NEMO routing optimization schemes and compares them from the aspects of data path, encapsulation message overhead and protocol complexity.After the analysis to the problems of nested NEMO pinball route and the packet multi-layer encapsulation, this thesis has designed nested NEMO routing optimization scheme NRO based on inner routing. In this solution, the root MR stands for all mobile nodes within NEMO and registers to their HAs, so that the packets forwarded from the MR's HA to the NEMO can be directly redirected to the foreign network linked by this nested NEMO, and it changes the way of nested encapsulation for the forwarding packets used in basic NEMO protocol. The NRO scheme also supports faster handoff, and achieves the goal of routing optimization for the NEMO mobile nodes. The analysis and simulation results show that compared with the NEMO basic support protocol this solution has reduced the cost of encapsulation packets and handoff delay to some extent, and has efficiently optimized the communication data path for the nodes within the NEMO.This thesis has also made an in-depth study to the micro-mobile management techniques, and has designed HRO router optimization scheme based on Hierarchical Mobile IP. In HRO scheme, MAP with location handover management is introduced and most of the registered messages are kept in the MAP domain, which not only optimizes the routing path, but also effectively alleviates the influence on the network performance when network topology dynamically changes. A new mobile routing protocol suited for the mobile network has been established. The route maintaining and updating algorithms used in the new routing protocol are discussed in detail. The analysis and simulation results show that HRO scheme has greatly reduced the transmission cost and handoff delay, and has improved the throughput and the transmission efficiency of data packets.