An Optimization Scheme Based On HMIPv6

As the main protocol for next generation Internet, mobile IPv6has the characteristics of better mobility support, security and scalability, which supports higher quality of network service. However, the standard mobile IPv6protocol couldn’t’t meet the requirement of network for some applications which need high Qos. Therefore, IETF proposed some improvement based on the standard mobile IPv6protocol, such as fast mobile IPv6, hierarchical Mobile IPv6and so on. These improved protocols are able to enhance the performance of network and reduce the handover latency and packet loss rate, but there are some shortcomings. For example, hierarchical Mobile IPv6introduced the MAP and divided the switch as Macro Mobility and Micro Mobility. The switching process of Macro Mobility is complicate while that of Micro Mobility is relatively simple. When the Macro Mobility of MN happen, the performance of network will be limited, and the handover latency and packet loss rate will both increase. Besides, the MAP most distant from the MN is selected to be registered by default, so that the high level MAP will have too much throughput, and this will become the bottleneck of communication. The problem that the network resource can not be fully used will appears.In this paper, we studied in hierarchical Mobile IPv6in details, then we analyzed the Macro Mobility switching procedure and proposed two aspects of improvement.First, we proposed a predicted Macro Mobility switching schema based on two tunnels, the main idea is to introduce the trigger mechanisms of link layer into the original protocol and configure the mobile node’s care-of address in advance. And before the link layer is disconnected, the registration to MAP and HA should be finished. After that, HA will bind with cache table while preserve both new and old binding information of mobile nodes, and these information will be used to establish two tunnels through which data being sent to mobile nodes can be forward to new and old MAPs, when the MN move into a new network, the corresponding binding relationship will be deleted according to the message sent to the home agent based on the new network information. This can decrease the switching delay of macro moving, also can solve the tennis sports problem of mobile nodes. Second, An MAP selection algorithm based on MN movement prediction is proposed to select suitable MAP. The simulation results show that MAP of each level could be used more appropriately based on the new algorithm, we achieve the object balancing network load and optimizing routes, the switching time delay and packet loss rate are both decreased, the overall performance of HMIPv6is improved.Finally, we simulate both the HMIPv6and improved algorithm on NS2platform. By analyzing the simulation results, we find the improved algorithm has better performance than HMIPv6in balancing network load,optimizing routes and decreasing the switching time delay and packet loss rate.