网络地址翻译及其应用

Network Address Translation and It's Application

现代信息社会随着Internet的飞速发展 ,IPv4下其可用的IP地址越来越少 .NAT(网络地址翻译 )协议的实现除了能解决IP地址耗尽的问题外 ,还可以完成隔离外界 ,保护公司和个人的隐私和安全 ,负载平衡 ,备份系统等功能 .而且人们对网络的服务和安全要求是IPv4无法满足的 ,IPv6的引入势在必行 .

Version 4 of the Internet Protocol (IPv4) has been in wide use for the past 25 years, but it has outlasted its effective lifetime and is straining to keep up with the demands of today's Internet. With the explosive development of the Internet, the IP address becomes more and more scarce. Using the NAT can temporally solve this problem. Besides, the IPv4 system cannot satisfy the newly requirements such as the QoS and the high security level rose from the ISPs. Therefore the introduction of IPv6 is necessary and impending. IPv6 is a natural evolution from IPv4 and attempts to address many of the older protocol's shortcomings. IPv6 is designed to keep up with the rapid growth of the Internet. The core specifications have been standardized through the IETF's IPng working group, and the NGtrans working group is studying issues surrounding the challenging task of smoothly transitioning from IPv4 to IPv6. The paper discusses the NAT and it's application in the evolution from the IPv4 to IPv6.