The Design And Research Of The IPv4-over-IPv6 Extended Mechanism For IPv6 Nodes

With the development of the IPv6 technology, native IPv6 backbones are emerging. However, vast applications and services still stay in IPv4 network. Interconnection of IPv4 and IPv6 networks over pure IPv6 backbones is required. IPv4-over-IPv6 is regarded as a good way for the interconnection of vast IPv4 network through pure IPv6 backbone. The principle of this mechanism is: build IPv4-over-IPv6 edge routers in IPv4 network exit, and the communication of IPv4 network across IPv6 backbone network can be realized, with the advantages of light, adaptive and simple management .And this mechanism is applicable to large-scale deployment. But with the continued development of IPv6 technology, pure IPv6 subnet will certainly appear in IPv6 backbone network. However, the needs of communication between IPv4 applications running on pure IPv6 nodes and IPv4 network can not be able to meet by all the presently transitional mechanisms (The reason is that there is no legitimate IPv4 addresses in pure IPv6 nodes), IPv4-over -IPv6 mechanism is no exception. In today and future, the promotion of IPv6 network will be greatly hindered by this limitation for the fact that IPv4 networks is still in the mainstream.In this paper, the work mainly of the following two aspects aims to design a mechanism for solving the problem issued.First, presently mainstream transitional mechanisms were deeply researched in this paper, and on the basis of this, the characteristics and inadequacies of IPv4-over-IPv6 mechanism have been detailed analysis, according to the reason of this mechanism's inadequacies, an IPv4-over-IPv6 extended mechanism purposed, and detailed design and analysis of this extended mechanism were given also.Secondly, in order to test the feasibility of this design, an IPv4-over-IPv6 intermediate layer driver based on windows platform was designed. Serve Kame Gateway as the IPv4-over-IPv6 edge router, and this two parts compose the basic model of this extended mechanisms, and the feasibility of this design has been tested through the experimental verification. OPNET also be used for analysis the whole ideas of this IPv4-over-IPv6 extended mechanism, and a conclusion reached according to test and simulation results.