隋着internet的迅猛发展，安全性已经成为网络互联技术中最关键的问题。本文全面介绍了internet防火墙技术与产品的发展历程；详细剖析了第四代防火墙的功能特色、关键技术、实现方法及抗攻击能力；同时简要描述了internet防火墙技术的发展趋势。-Sui with the rapid development of internet, security, network interconnect technology has become the most crucial problem. This comprehensive introduction to internet firewall technology and product development process　a detailed analysis of the functions of the fourth generation firewall features, the key technology, methods and anti-attack　along with a brief descr iption of the internet firewall technology trends.