防火墙——安全网络的前哨

Firewall——Guard for Network safety

防火墙是在内部网和外部网之间实施安全防范的系统,可分为数据包过滤型、代理服务型、复合型及其它类型,常见的结构有子网过滤结构和主机过滤结构。本文分析了各类防火墙的优缺点,提供了上述两种防火墙的具体实现方法。

This paper describes the advantages and disadvantages of various firewalls including packet filter, proxy service, hybrid and others, and provides the implementation methods for the two commonly seen types, namely the subnet and host filtering structures.