Linux下防火墙透明模式的原理及实现

Principle and Implement of Transparent Mode on Linux Firewall

随着Internet网络的广泛应用,网络安全越来越受到人们的重视。防火墙是提高网络安全最基本也是最有效的手段。工作于透明模式下的防火墙可以极大地简化防火墙的配置并提高防火墙自身的安全性。文章分析了防火墙透明接入时带来的ARP失效问题,并分别提出了用ARP代理技术和桥技术解决该问题的两种方法,同时给出了简单的实现。

As Internet is widely used, people have become increasingly aware of the importance of network security. Firewall is one of the most fundamental and efficient means to improve the network security. Transparent mode can simplify the configuration of firewall and enhance the security. This paper firstly analyzes the problem of ARP losing efficacy resulting from transparent connecting of firewall, then introduces tow methods to settle the problem: one is ARP proxy, the other is bridge.