According to the report released by the China Internet Information Center in Octorber2009, the total quantity of internet users in China had been counted to be3,380millions up until the end of September in2009, which means that in2010, the total number of internet users in China exceeded the whole population of the USA, and was as well as the most absolute number around the world.But, there are merely73,650,432IPV4address, obviously a large vacancy exists.A good solution is considered to be IPV6, however it is not realistic to substitute all the existing devices in the IPV4network with IPV6network, and a more possible situation is that both network will coexist for quite a long period in the foreseeable future.Therefore, the communication problem between the two kind of network is supposed to be solved.Till now, there are three practical methods, each of which has advantages and disadvantages respectively.It will be a promising project to improve these three methods in order to achieve more efficient communication between IPV4and IPV6.In this thesis, the features of the IPV6network protocols is probed firstly, followed by the comparison with the IPV4network protocols.The features that these two protocols are not compatible, the essential of transition to IPV6, as well as the principle and technique difficulties of transition are analyzed in depth in the following part.Meanwhile, a detailed analysis upon existing transition mechanisms is made, including a further research of the characteristics of each mechanism and a provement of network transition solution for NAT-PT technique on the basis of application environment. Core data structure in the art has been improved, wherein the network address conversion using the HASH+linked list data structure such that the address mapping table to find the speed is increased to improve the conversion efficiency of the address. NAT-PT technology based on improved the IPV6translation gateway system simulation model, network simulation analysis turned gateway system to test its performance. Analysis results show that:The conclusion of this paper can be used as a reference scenario applications from IPV4to IPV6network transition period. |