The Study Of The Cross Layer Switch Management Model Of The Mobile Internet And Implementation

With the rapid development and popularity of the internet technology and mobile communication technology, and increasing integration of their business, the boundary between the computer internet and mobile communication network is gradually disappearing, and evolved into the next generation communication network that can unify the computer network and the mobile communication network, is called as the mobile Internet.The next generation mobile Internet will be the integration of heterogeneous networks, which composed of a variety of wireless access technologies (such as GPRS, UMTS, WLAN, WiMax,4G and etc), different wireless networks complement with each other to meet different user needs. At the same time, with the emergence and widespread use of the multi-mode terminals, such as the multi-mode mobile phones and laptop computers with multi-interface, people can dynamically access the best network by multi-mode terminal with a variety of different wireless air interface.In order to allow the users to move freely and handover seamlessly, require a good network mobility management.Mobile IP protocol as the network layer mobility management scheme, which is characterized by shielding the underlying differences between the different access technologies and be transparent to the upper layer protocol,can effectively support the interoperability between heterogeneous networks. Therefore, the mobile IP protocol has caused great concern in academia and industry,ITU, IETF,3GPP,3GPP2, and many other international standardization organizations made a great deal of research. In addition, as the IPv4protocol can not meet the development requirements of the future network, next generation all-IP mobile Internet will be based on mobile IPv6platform.However, both the basic Mobile IPv6protocol, or its modified protocols such as Fast Mobile IPv6protocol and Hierarchical Mobile IPv6protccol, to some extent, there is a larger handover latency and high packet loss rate, can not meet requirements of the real-time business, must be improved. After analysis, the strict independence between the protocol layers is the main source of delay increase, leading to a lot of delay and packets loss. Therefore, to break the independence between the various protocol layers and to achieve information exchange between different protocol stack layers is a fundamental way to improve the handover mechanism of the Mobile IPv6.Handover is the key mechanism in the mobility management, including three parts: system discovery, handover decision and handover execute. In general,the traditional handover decision only select the bottom parameters, such as received signal strength and the trigger condition is just a pre-set threshold. In the heterogeneous network, this scheme is not efficient.To the difference with parallel handover, vertical handoff must be considered bandwidth, delay, costs, packet loss rates, user preferences and other attributes.According to the analysis and study of the current handover management protocols,and combined with the characteristics of the next generation mobile Internet,a cross-layer handoff management model was designed.In the model,the core issue is handover decision,including network selection and handover trigger.In the aspect of network selection, we propose a dynamic weight-based network selection algorithm (DWSA). Analysis the network selection models under various states, full account of the important role of the business types and user policies in the network selection. Based on the traditional AHP method to determine the weight of each attribute, dynamically adjusting the weights to achieve the effect of the business types and user policies in the network selection. Use the grey relational analysis to sort of alternative networks and choose the highest ranking network.In the aspect of handoff trigger, we propose a link layer information-based cross-layer handoff management protocol (CL-FHMIPv6), analyze the processes and operating mechanisms of the protocol, and use the NS2simulation tool to simulation and analysis protocol performance, such as delay, packet loss rate, handover efficiency. The results show that the protocol significantly reduces the latency and packet loss rate and improve the handover efficiency.