Design & Implement Of Base Station Specific Routing-Based Handoff Mechanism In Cellular IP

With the development of computer networks and wireless networks,regular IP can't finish the wireless access of Internet There needs a new scheme to solve this problem。To support the mobility of Mobile Host,IETF introduces the Mobile IP as its solution. The basic scheme is to use Care—of-Address(COA)and Tunneling methods The advantages of Mobile IP are simplicity and extensibility。Mobile IP is now the standard for supporting mobility in IP networks. It provides seamless mobility by hiding the change of IPaddress when a mobile host moves between IP subnets. Nevertheless, Mobile IP is not designed to support fast handoff and seamless mobility in handoff-intensive environments. Several micro-mobility protocols have been proposed to support host mobility with frequent handoffs within a domain. Cellular IP, HAWAII(Handoff Aware Wireless Access Internet Infrastructure) and Hierarchical Mobile IP are some of the popular IP micro-mobility protocols. Cellular IP complements Mobile IP with support for fast, seamless and local handoff control, and IP paging.In this paper, we illuminated the limitation of current Cellular IP protocol firstly,then proposed a new handoff mechanism which is a modification to the existing indirect handoff mechanism--Base Station Specific Routing , and constitutes a new way to handoff to the new base station where the handoff is initiated along the old base station, resulting in reduced handoff delay and packet loss.In the end,the new mechanism is proved by simulation. The content of the paper is introduces in Chapter 1.Chapter 2 summarizes Mobile IP ,CellularIP protocols and the key technologies of Indirect Handoff Mechanism.The new design of base station specific routing based on handoff mechanism in Cellular IP is given in Chapter 3. Chapter 4 analyses and evaluates the new handoff mechanism based on some theories. Chapter 5 provides the basic knowledge of NS and the practical parts of the paper. Chapter 6 assesses the new handoff mechanism based on the data provided through simulating in NS-2 and in Chapter 7 there is a brief summary of this paper and its coming work in the future.