The Design And The Implementation Of NAT-PT For IPv4 Towards IPv6 Transition Technique

Nowadays, IPv4 is the broadly used protocol in the Internet. It's constructedin late 70s. Along with the rapid development of Internet technology, the sizeof networks expanded enormously in an unexpected rate causing shortage ofIP addresses and expansion of router tables. These cause IPv4 being notsuitable for current and future Internet development requirements. Hence thenewer generation IPv6 was developed and can support a huge address space,better header format, and extension headers with new options etc. From thepoint of development uptrend of Internet, replacing all IPv4 addresses withIPv6 addresses, a final and complete solution can be realized. Hence it's avery necessary technical approach. But a complete upgrade from IPv4addresses to IPv6 is a very long transition process. At the moment we canonly make an IPv4 and IPv6 co-existing network. Hence this became themajor task in year 2000 for IETF IPV6 work group. At the moment, there arethree kinds of techniques for IPv4 to IPv6 transition;Dual Stack technique,Tunnel technique and NAT-PT technique (Network Address Translation-Protocol Translation). This article explains all three techniques in detail, at thesame time, considering current transition status and requirements NAT-PT ismainly focused and deeply analyzed. NAT-PT realizes the communicationbetween only IPv4 network host and only IPv6 network host. And resolves theproblems like the problems with interconnections of IPv4 hosts to IPv6servers and IPv6 hosts to IPv4 servers in the IPv4/ IPv6 co-existing networks.The solutions provided in this theses are based on Linux platform, and uses acomputer which possesses routing functions and Dual Stack support as atranslation gateway, several pure protocol supporting computers as IPv4 andIPv6 networks. This setup is used to realize the interconnections between onlyIPv4 and only IPv6 networks.