Research On The Route Optimization Technologies In Mobile IPv6 Handover Mechanism

In order to support mobility by next generation Internet, IETF proposes Mobile IPv6 (MIPv6) on the basis of IPv6. Handover is one of the key technologies in MIPv6. Focusing on the defects of MIPv6 handover mechanism, IETF proposes Fast Handover for MIPv6 (FMIPv6), Hierarchical Mobile IPv6 (HMIPv6) and Fast Handover for Hierarchical MIPv6 (F-HMIPv6). Even if they are not entirely successful on Route optimization, these schemes make an improvement on Handover delay. Combining the characteristics of FMIPv6 and HMIPv6 F-HMIPv6 provides faster and smoother handover mechanism, however it follows the Route strategy of HMIPv6 namely packet forwarding is achieved by default through MAP in MAP domain. Under this method F-HMIPv6 forwards the packet from CN to MN by tunnel, as a result MAP does not support Route optimization in MAP domain meanwhile easily causes MAP congestion.Aim at F-HMIPv6 Route optimization, this paper proposes F-HMIPv6 scheme supporting Route optimization which introduces Border Router to assist MAP to forward packet so as to solve congestion in MAP. As this scheme still uses forwarding packet through third party node by tunnel, although it reduces signaling overhead such as registration binding update under CN and back binding confirmation under CN, by comparing with CN under Route optimization and MN direct communication, it is certain that packet transition delay exists. Thus this paper proposes a Route selection mechanism within triangle Route and Route optimization in MAP domain. This scheme analyzes the cost by modeling and takes cost optimization as objective, analyzing the parameters in a certain network environment, and uses adaptive route selection strategy. Finally, this paper implements these two schemes in NS-2 network simulation environment to make a comparison with original F-HMIPv6.