QoS Research Based On Mobile IP Network

In recent years, with the rapid development of mobile communication technology and wireless access technology, PDA and laptops portable mobile devices have been used widely. Users request much higher about the mobility of devices. Mobility support becomes a necessary requirement of the network. IETF group brought about Mobile IPv6 protocol in 2004. MIPv6 makes it possible that mobile node which handovers across different subnets can still communicate continually. However MIPv6 is a terminal based global mobility management protocol, that is MIPv6 centers around terminals, besides, terminals need to participate in handover procedure, which result in long handover delay, additional mobility management in terminal protocol stack and other drawbacks. So it is not suitable for the future mobility, which requires low handover delay, low-complexity and manageability.Because of so many drawbacks of global mobility management protocol, The NetLMM working group within IETF recommended a set of goals to support localized mobility. IETF group brought about proxy mobile IPv6 protocol (PMIPv6) in 2008, which can meet the mobility demand of a large number of terminals in local scope. PMIPv6 is a network based local mobility management protocol, in which the network entities on behalf of mobile terminals perform handoff-related operations, relieve much burden of mobile terminals. It reduces the signaling interaction during the procedure of mobile handover and thereby saves precious wireless bandwidth resources. It also helps to reduce the handover delay during the procedure of the mobile terminal handover, and enhances the network manageability.In this paper, we have deeply studied relevant key issues of mobile node handover about the network-based local mobility management. First of all, generally summed up in recent years the network-based local mobility management research status as well as the trends of research at home and abroad, introduced the protocol principle of PMIPv6 as well as the operation principle of commonly used functional entities. Then we did a detailed analysis of inter-domain handover method of PMIPv6, next focus on the intra-domain handover method of PMIPv6, pointing out the drawbacks that the handover delay and packet loss rate is still relatively large, which affect the application of some delay sensitive traffic. This paper proposed an improved intra-domain handover management solution based on PMIPv6. When new mobile access gateway which mobile node attached to sends PBU message to LMA, LMA sends back the change with CBU message to related MAGs in the new solution. Which can achieve a bidirectional, smooth and fast transition from the old optimized path to a new one after handover. As a result, new solution can efficiently reduce the handover delay as well as the possibility of out-of-sequence delivery problem. At last, we did a detailed theoretical analysis of the handover delay performance of the two different intra-domain handover solutions and did a simulation with the powerful network simulation tool NS-2. Result of simulation can prove the theoretical analysis and achieve the desired results.