Research On Key Technologies Of Multiple Network Convergence In Future Mobile Telecommunication System

Mobile telecommunication system in the future will be heterogeneous converged networks, which based on all IP (Internet protocol) technology, integrate different types of radio access technology, support the seamless handover and roaming between heterogeneous networks. Since different networks has different system architecture and lower layer technologies, the mobility management technology, QoS guarantee mechanism and Authentication, Authorization and Accounting (AAA) of different networks are different, these solutions in single network cannot support the cooperation between different networks. The convergence of heterogeneous networks pose a large number of challenging issues, such as, QoS guarantee and security, user experience of seamless mobility, and the overall system performance of the integrated networks. In order to meet the demand for the development of mulitple networks convergence, provide the best connection for each user under any circumstance, guarantee the seamless reliable service, and imporve the performance and efficiency of the integrated networks, the dynamic QoS guarantee mechanism, adaptive mobility management scheme and fast mobile AAA solution, which are open, high efficient and unrelated to access technology should be designed. This paper investigated on these three topics and the contribution of the paper is as follows:(1) A dynamic QoS reservation mechanism (RM-DQR) based on location information in the framework of HMIPv6 is proposed. The handover and traffic intensity in history can be measured periodically. According to the results reported, neighbor cells, which have high handover or traffic intensity between each other, can be deployed in the management region of the same MAP. Then the re-reservation path can be controlled in the intra-domain when new reservation path should be established. The proposed scheme can greatly reduce the QoS signaling cost and shorten the delay of re-reservation path establishment.(2) In order to solve the problems of load convergence and single point of failure, a novel adaptive mobility management scheme based on hierarchical mobile IP is proposed, including the adaptive MAP selection scheme and high efficient MAP failure detection and recovery mechanism. The adaptive MAP selection scheme is based on distributed MAP enviroment, the lower layer information are provided by adopting the Layer 2 trigger mechanism, and the policy based MAP selection can efficiently achieve load balancing. The proposed high efficient MAP failure detection and recovery mechanism adopts ICMPv6 protocol to detect the MAP failure, which reduces the failure detection time, the failure recovery process is accelerated by using the primary and backup mobility binding of mobile nodes. The performance of the adaptive mobility management scheme are analysed theoretically, and are compared with the standard hierarchical mobile IPv6 protocol. Mathematical and simulation results show that the MAP reliability, packet loss rate and MAP failure detection and recovery time are optimized with the proposed adaptive mobility management scheme.(3) By analyzing the disadvantages of current mobile IP and AAA integration schemes, an enhanced AAA authentication scheme (E-AAA) is proposed. This scheme introduces the principle of hierarchical mobile IPv6, which works out the switching key generation and management specifically, in order to ensure the safety of switching process. In addition, under the premise that security is guaranteed, this scheme further resolves the critical overhead because of the authentication. It not only makes the authentication cost in the region reduced, but also the cost inter-domain.(4)An optimal AAA integration scheme for 3GPP-WLAN has been proposed. A framework of integration authentication is put forward, and then the theoretical analysis and the simulation are carried out based on the integration authentication architecture. As the simulation result shown, the system overhead can be reduced to the minimum, as long as the number of authentication vector group AV, AV request and re-authentication times for each AV is set reasonably. This scheme provides theoretical guidance for AAA facility deployment and commercial deployment of Mobile IPv6 in the future.