| With the rapid development of internet, mobile wireless access technology and communication technology, mobile IP technology has become an important application technology and development direction on next-generation wireless network. With its support higher bandwidth and better security and mobility, Mobile IPv6 will replace IPv4 to become the next generation mobile network core technology gradually in the global context. The research on the key technology of Mobile IPv6 is of great practical significance. However, some problems still exist in the transfer management mechanism of current representative MIPv6, FMIPv6, HMIPv6 and FHMIPv6 protocols, such as the large delay, the high dropout rate and low throughput and so on. The solution can not meet the demand of fast-moving hosts, especially the communication requirements of frequently handoff mobile host in ping-pong movement.Ping-pong handoff will produce frequent updates in location. A large number of location updates and system communication overhead will cause some ill effects: the resources just to be reserved leave will have to be released because mobile nodes leaves, or the resources newly released will have to be reserved because mobile nodes return back. the frequent reservation and release of resources will not only increase the burden of the regional network signaling, but also increase handoff delay and packet loss rate, which can not meet the QoS demands of mobile users. Therefore, when mobile nodes are in Ping-pong movement, it is an important research topic on how to manage resources to reduce QoS handoff signaling and handoff delay. Based on the Ping-pong handoff mobile IPv6 network, it is becoming an important research areas on how to provide fast, stable and reliable communications services.Multi-protocol Label Switch (MPLS) is a packet transmitted mechanisms based on fixed-length labels. The combination between MPLS with mobile IPv6 can increase packet transmitting rate and improve the quality of services. But the combination makes the handoff delay of mobile nodes may be as a result of the introduction of MIPv6 protocols operation, or the re-establishment label switch path (LSP). Moreover, with the difference of handoff methods, packet loss rate are also higher than the Mobile IP to different degrees. In addition, because mobile nodes in the process of the transfer handoff may result in a handoff failure, we hope that mobile nodes own failure recovery capabilities. Therefore, it is particularly important to design a handoff solution with low delay, low packet loss rate and failure recovery capability in MPLS-based mobile IPv6 network environment.The main content of the thesis is as follows:1. Aiming at the problems of the handoff delay, high packet loss rate, a decline throughput in the Ping-pong handoff mode of FMIPv6, HMIPv6 and FHMIPv6, the thesis proposes the ping-pong handoff idea based on the two-way tunnel PAR-NAR transmitted mechanism. The idea is applied in FMIPv6 and FHMIPv6 respectively, which have achieved two solutions: FMIPv6-PP FHMIPv6-PP.(1) The working principles, technical features and performance indicators of Mobile IPv6, FMIPv6, HMIPv6 and FHMIPv6 have been made in-depth research and analysis. Their existing shortcomings are pointed out that: One is short of doing specific quantification in handoff delay, packet loss rate and the throughput at a specific situation; and the second is that initial designers of mobile IPv6 protocol do not take into account the problem of ping-pong handoff in mobile communications. When the integration mobile communication networks with the internet computer becomes an inevitable trend, the solutions on the Ping-pong handoff in Mobile IPv6 must transform the existing protocols and key technologies.(2) The thesis proposed a kind of new Ping-pong handoff idea based on the PAR-NAR bidirectional tunnel transmitted mechanism, and two new solutions respectively: FMIPv6-PP and FHMIPv6-PP. The solution relied on the definition of new Hop-by-Hop options header TM, PCoA table and two-way tunnel forms, and the establishment and maintenance of two-way tunnel around MN handoff between two access routers, for the data packets transmitted rapidly during the handoff of the ping-pong. The analysis of theory and simulation showed that: the idea and solution proposed in this thesis can achieve very good effects in reducing the handoff delay and packet loss rate, improving the throughput and the QoS greatly. Other than mobile IPv6 protocol handoff mode more suitable for ping-pong. It is more suitable for ping-pong handoff mode than mobile IPv6 protocol.The establishment of a rapid predictive Mobile IPv6 new solution has the following advantages:①In predictive FMIPv6, MN rely on the underlying information (e.g. the strength of access point signal) to judge when it transition to which NAR takes place, which will produce a mobile detection delay. The proposed solution owns the same operation process. The difference lies in that MN does not judge which NAR to transfer, but direct transfer to PAR. This will simplify the operation of the transfer of MN and more easy to realize.②Compared to predictive FMIPv6, the proposed solution omitted the configuration of new transfer address, and detection of repeated address, thus reducing the delay of address configuration.③Compared to predictive FMIPv6, the solution uses the two-way tunnel between the NAR and PAR to transmit text, and there is no need of MN registration process home agent (HA) and the associated communications nodes (CN) repeatedly. This feature not only reduced the MN handoff delay and handoff signaling effectively.⑶Do the experimental simulation of Mobile IPv6 fast handoff, level handoff, mobile rapid level, FMIPv6-FHMIPv6-PP, and carried out a detailed performance analysis of handoff delay, packet loss and throughput of the five solutions.⒉Summarize the shortcomings of the existing solutions and propose a predictive Fast handoff solution integration Mobile IPv6 with MPLS. Aiming at those problems, such as large delay for the establishment of label switching path (LSP), high packet loss rate and error-free recovery and so on in existing MPLS and IPv6 combined solution, the thesis proposed a kind of predictive fast handoff solution which integrates Mobile IPv6 with MPLS. By defining forecast information table and predictive MPLS transfer handoff algorithm, MN selects access routers in accordance with their own needs before the transfer handoff, and the early completion of its cross-router LSP building, so as to achieve the minimum of delay of the MN transfer handoff. In addition, the predictive MPLS transfer handoff algorithm makes this solution with fault recovery capability; the improvement of LSP topology and dual broadcast mechanism reduce the packet loss rate effectively. The theoretical analysis and simulation show that the proposed solution owns less handoff delay and packet loss rate than existing solutions, and with failure recovery capabilities.In this thesis, the innovation embodied in the following aspects:⒈On the basis of Analysis of the advantages and disadvantages of Mobile IPv6 and its expansion protocol, the thesis proposed the idea of ping-pong handoff based on two-way tunnel PAR-NAR transmitted mechanism.⒉The application of new ideas to FMIPv6 resulted in the rapid mobile IPv6 solution based on the ping-pong effect(FMIPv6-PP).⒊The FMIPv6-PP could not differentiate the movement in the domain and among the domains. In order to solve the problem of remote registration costing too much, the hierarchical structure was introduced to improve PP-FMIPv6, which formed a rapid-level Mobile IPv6 (FHMIPv6-PP) based on the ping-pong handoff.⒋A kind of predictive fast handoff solution which integrates Mobile IPv6 with MPLS is proposed, which realized the minimum of delay of the MN transfer handoff. The improvements of LSP topology and the use of dual broadcast mechanism can reduce the packet loss rate effectively. What's more, the proposed predictive MPLS transfer handoff algorithm owns the failure recovery capabilities.In summary, this thesis firmly grasps the core of the next generation network technology - Mobile IPv6 and its key technology, starting from the in-depth research and analysis on the working principle, technical characteristics, the main handoff process and performance indicators of Mobile IPv6, FMIPv6, HMIPv6 and FHMIPv6. Aimed at the key issue of how to provide fast, stable and reliable communications services in the ping-pong handoff based Mobile IPv6 network, the thesis proposed a ping-pong handoff idea based on PAR-NAR two-way tunnel handoff mechanism to solve some problems in a number of existing solutions. The idea is applied in FMIPv6 and FHMIPv6 respectively, which have achieved two solutions: FMIPv6-PP FHMIPv6-PP, which can reduce the handoff delay and the packet loss rate, increase the throughput, and improve the QoS. The solution has a certain theoretical and practical value. At the same time, this thesis has made some research on combining mobile IP with MPLS, and proposed a kind of predictive fast handoff solution on the basis of the study of problems in existing solutions which integrates Mobile IPv6 with MPLS. The solution can make full use of the advantages of two kinds of technologies, and make a great progress in reducing the MN transfer handoff delay, the packet loss rate, and the failure recovery capability, and further enhancing the network performance. The feasibility and superiority of the solution has been proved through simulation experiment. Because of the inadequacies of author and the limited research time, the work presented in the thesis is only the initial stage, for example, only part of the Mobile IPv6 handoff performance was discussed, and the security, authentication and other issues of FMIPv6-PP and FHMIPv6-PP have not been considered, all of which need to do more in-depth research at the next step.
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