| With the rapid development of Internet, It has been an important subject how to make IPv4 gradually transfer into IPv6 in the study of Internet area. From IPv4 to IPv6, change will inevitably bring a new revolution on the Internet, either hardware or software will have a new development. It has become the primary problem how to anchive connection of IPv4/IPv6 and hide the underlying details of users based on exciting IPv4 network infrastructure. There are now a variety of transition techniques including dual stack techniques, tunneling technology and address conversion and protocol translation (NAT-PT) techniques. Among this techniques, NAT-PT is the most important transitional techniques which implements the communication of IPv4 node to IPv6 node through packet address transferred and protocol interpreted.This dissertation describes the emergence of Internet and IP protocols, development and research, discusses the new features of IPv6, addressing method and packet format, compares the message format of IPv4/IPv6 and the three transitional techniques, especially analyzed the dynamic NAT-PT techniques. Based on the NAT-PT gateway conversion principle and implementation process, a dynamic NAT-PT gateway is designed and implemented. Combined with DNS-ALG techniques, the problem of communication from IPv4 to IPv6 is sovled and the two-way communication between IPv4 and IPv6 is realized.Finally, the dynamic NAT-PT gateway has been achieved in the Linux environment. The whole gateway consists of three modules:address translation module NAT, protocol conversion module PT, Application Layer Gateway module DNS-ALG.The test results show that the NAT-PT gateway can realize two-way communication between IPv4 and IPv6. |
PDF Full Text Request