Study And Pratice On Transitional Technology Of IPv6 Visit IPv4 Network

With the development of computer networks, especially the development of Internet,IPv4 has not been adapting to the need of this rapid development and IPv6 will come into stage soon. Compared with IPv4, IPv6 has some characteristics: simplified header and extension; big enough address space and hierarchy address architecture; Plug and Play internet working; authentication and encryption on network layer; support on service quality; better support on mobile communication. After a period of coexistence of IPv4 and Ipv6, IPv6 will take place of IPv4 and become the main one on the Internet.Currently, we are still in the period of transition from IPv4 to IPv6 and the most part of Ipv6 networks are still in the period of research. In the Internet Ocean based on IPv4,these IPv6 networks are just some little islands. But with the development of IPv6, we can foresee that more and more users will want to get service based on IPv6, more and more IPv6 networks will join in Internet. Additional, in the period of migration, IPv6 and IPv4 will exist together, so IPv6 must visit IPv4 networks, and the visit technology is of importance for research and improment.In this thesis, I discuss the shortcomings of IPv4, analyze the certainly advent of new Internet protocol-IPv6. Then this thesis introduces the fundament and new characteristics of IPv6,discusses and compares a variety of transition mechanisms that IP v6 visits IPv4 networks, while, put forward my own opinion. At last, I practice IPv6 dispose and NAT-PT technology.