The Optimization On Macro Handover Of Hierarchical Mobile IPv6

As the core of the next-generation Internet, IPv6 have good support for the mobility. However, the real-time business such as video and audio and the technology of 3G and 4G in the mobile communication require the seamless and smooth handover during the movement, which make higher demands on the handover performance of mobile IPv6. IETF put forward some standards such as RFC3775, RFC4068, RFC4140, which describe the standard mobile IPv6, Fast handovers for mobile IPv6(FMIPv6) and Hierarchical mobile IPv6 mobility management(HMIPv6) respectively. FMIPv6 mainly exploits the mechanism of link-layer anticipation and tunnel. HMIPv6 conducts local mobility management by introducing the mobile point anchor (MAP). These schemes improve the handover performance and decrease the handover latency, but still exist some faults, for example the complex procedure of binding registration that leads to the longer latency in the macro handover of HMIPv6.This thesis researches the problem in the macro movement of HMIPv6. The mobile node(MN) begin to perform the network-layer handover, such as the the Care-of Address configuration and duplication address detection. Then the MN sends the binding update message to the MAP as well as the home agent and correspondent node that increase the handover latency, which cannot optimize the macro handover comparing to the MIPv6.In order to solve this problem, we proposes a protocol named Tunnel-based Fast Macro Handover (TBFMH). The main work is as the following.First, the mobile node acquires care-of address on the grounds of handover information and conducts duplication address detection to make sure that the address is unique in advance.Second, the TBFMH completes the local binding update during the tunnel establishment by modifying the format of message, which makes the MAP pre-perform the binding. When MN arrives the new MAP, it only performs the normal register to the HA and CN as the MIPv6, which reduce the binding update cost and the total handover latency.Third, the new protocol transmit the packets during the handover procedure by the tunnel and make the MAP cache these packets which will send to the MN after it entering into the new MAP, which decrease the possibility of packet loss.Finally, we build the appropriate topological structure to simulate the HMIPv6 and TBFMH protocols with the help of the NS2 simulator platform and the FHMIP 1.3.1 module, and analyze the experimental data. The simulation results demonstrate that TBFMH can decrease the handover latency and reduce the packet loss rate compared to the primary protocol, which effectively improve the performance of macro handover.