By adding the mod_security module to the Apache Web server, you can change the reverse proxy server to an application gateway and provide even more security to the Web application.

通过在Apache Web服务器中添加mod_security模块，即可将反向代理服务器改为应用网关，并为Web应用程序提供更高的安全性。

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The truly paranoid may elect to use the 2.4 kernels' Netfilter4 facility (adding stateful packet filtering) or a commercial application-level proxy gateway.

CNN: Analysis: Linux security

The MobileSpan Gateway is a central server application that acts as a transparent browser and document proxy on the corporate network.

FORBES: Advantages of the MobileSpan Approach