Research On The Smooth Handover In All-IP Network

At present, the world traditioal voice service every year’s rate of increment is 8%, but the packets service rate of increment surpasses 100%. Especially Internet, since the mid-90s its service volume continuously by 300% speeds in explosively growth, IP technique will defeat other each kind of technique finally. The perfect combination of the IP technique with mobile communication technique is enabling data service to take palce transformation the same as voice service; it will create the happy blueprint of personal communication: The humanity will communicate with any kind of media with other people in any time, any place. IP network has become irreversible tendency completely.The network service’s explosive growth makes the traffic of All-IP network to increase large scale, it will cause network architecture to tend to smaller region of hierarchical management, the characteristic of dividing smaller region is that, mobile agents have high overlap region, Moreover, in All-IP network, mobile nodes have extremely high mobility, this kind of high mobility will cause a more frequent handover, will thus decrease the smoothness at handover. According to Mounir Frikha and Lilia Maalej literature and the process of LEO-MSSs mobility model’s analysis and improvement, verify that it will decrease obviously Dropping Probability at Handover after mobile nodes enter the overlap region. Using this characteristic, this article, for the question of delay, packets loss, and dropping probability at handover, and so on, proposed the overlap thought and the overlap computation, as well as the pre-handover and handover mechanism based on HMIPv6 protocol. The current trigger condition, the prefix match of broadcasting router, is changed, instead, the overlap computation, for protected delay.Due to high mobility of mobile nodes, high overlap of mobile agents and massive network traffic, some kinds of micro-mobility protocol IETF proposed can not deal with the smoothness of All-IP network further. So the research of queue algorithm in All-IP network is important except smooth mechanism, especially dispatch algorithm. The key is, that the priority of the average queue size in system at the low level, but is not system throughput. Only if guarantee delay at handover, guarantee the good performance of handover management. One of All-IP network’s main features is the massive non-real-time data service. In an access point, the total of all user needs often surpass capacity which the access point have, must therefore have the dispatcher in access point to assign resources according to user request, grade service. The environment of All-IP network is more complex. Mainly manifests, it is different with wired network, the degree of congestion control not only relate with queue size, but also with the busy or idle degree of wireless channel around mobile nodes. Moreover, when detect congestion, adopts what kind of control policy and decrease system overload as soon as possible. IETF recommend Active Queue Management (AQM) Algorithm, eg. RED, as the method of network congestion control, but AQM is only suitable for wired environment, not for All-IP network. Therefore, this article proposed the queue algorithm adapted handover management of All-IP network. Mainly completes the following work:1 Overlap region thought and computationBased on Mounir Frikha and Lilia Maalej literature, and the process of LEO-MSSs mobility model’s analysis and improvement, as well as the characteristic of All-IP network, experiment and theory confirmed that when mobile nodes enter the overlap region, its Dropping Probability at Handover will decrease obviously. Using this characteristic which mobile nodes located at the overlap region, this article proposed the overlap thought, and gave how mobile nodes compute the overlap region.2 the overlap handover mechanism based on HMIPv6Analyzed and compared the three kinds of micro-mobility protocol, that is, Cellular IP, HAWAII, HMIPv6, and based on the overlap computation in second chapter and HMIPv6, this article proposed the pre-handover and handover mechanism based on HMIPv6.3 the queue algorithm in handover managemen of All-IP networkAnalyzed and compared RED, AVQ and QLT algorithm, these three kind of typical active queue management algorithm, as well as the characteristic of All-IP network on queue algorithm, by LEO-MSSs mobility model’s analysis and improvement process, this article obtained handover probability PHi based on the overlap thought, proposed queue algorithm suitable for handover management of All-IP network.