Proxy Web Servers

The HTTP protocol originally required a direct TCP/IP connection between the web browser and the web server. This architecture did not work well with many corporate network architectures that employed firewalls between their internal and external networks. This led to the development of proxy web servers. Most web browsers allow the user to specify an optional proxy server. A proxy server is simply an intermediate server that acts as a relay between client browsers on an internal network and external web servers as shown in Figure 20-1.

Figure 20-1. Proxy Web Server Architecture