Research On The Key Technologies Of Mobility Management For IPv6

Mobility management scheme is the solution for supporting maintains communication when a communication terminal node is moving. Mobile IPv6 technology is a major mobility management scheme in IPv6 network. Handover of mobile node is the focal problem of mobile IP. To maintain the normal communication after a handover has taken place in mobile IPv6, the mobile node must perform location registration to some entity in the network for reporting its position. This will cause a series of problems as the following.When a mobile node enter a new subnet, the correspondent nodes do not know its current position before the location registration has finished. Therefore, the packets that are sent to the mobile node can not be routed to its current location correctly. in this case, a short interruption of communication occurs, it led to the communication delay of handover. Massive signaling messages generated by the location registration need to transfer over the network, it brought out additional network overhead. Moreover, the mobility management for mobile nodes may result in data packets delivering throught a subordinate route Instead of the optimal route. This will generate additional packet transmission overhead. In addition,the messages generated by the location registration are the potential targets of attackers. In addition, the wireless link of mobile IP network makes use of the open media, computing and storage resource of mobile node is relatively limited. So that, these security risks may result in more serious consequences.To solve these problems, this thesis have made deep analysis and studied of Mobile IPv6 and related mobility management and handover algorithms. On this basis, Research work is carried out in the following areas, and obtained certain positive result.1 we conducted the further studies of location management and packet routing procedure in Hierarchical Mobile IPv6, and analyzed the factors that cause the handover overhead and delay. An improved hierarchical Mobile IPv6 scheme is presented for improving performance of Hierarchical Mobile IPv6 by means of reducing handover latency and costs. When the mobile node occurred the handover between two domains, the scheme reduced the handoff delay through using previous mobile anchor point(MAP) as an agent of the current MAP. In addition, the scheme provides several different options of location registration policy for the handover, the mobile node can select the strategy of location registration according to its movement characteristics to reduce overhead.2 An analytical method is proposed to minimize location registration and packet delivering cost. The analytical method can predict the subsequent handover of a mobile node, and the mobile node can make use of its movement characteristics to calculate the respectively total costs of location registration and packet delivering through employ different strategies in order to select the best strategy.3 we proposes a dynamic adaptive mobility management scheme, in which two layers logical structure is established base on monolayer physical structure. The high level MAPs of the two layers structure and their management region are not fixed. Mobile nodes can adjust their logical structure of mobility management according to the movement characteristics to reduce costs and achieve high adaptability. The scheme optimized the costs while avoid the problems of overloading and single point of failure brought by centralized structure.4 we conducted the studies the potential security risk brought by the messages of the binding update and analyzed the existing certification mechanisms. To solve the security problem brought by Return Routability mechanism which messages can not be verified by the certificate authority, we propose a Binding Update scheme which messages are certificated by Return Routability Mechanism combined with the Authentication Authorization and Accounting(AAA)certification. The scheme make use of AAA server to certificate the messages brought by the binding update while the authentication to mobile node for visiting the foreign network and location registration are combined to proceed simultaneously. Thereby, the performance of authentication and binding update is improved.It is verified that the theories and key technologies of mobility management for IPv6 presented in this thesis are able to solve effectively the handover latency,overhead problems and potential safety issues in the mobile IPv6 by the results of theoretical analysis and simulation. Those theories and technologies can be expected played a positive role for development and application of the next generation network mobility management technology.