A proxy server is a computer that offers a computer network service allowing users to make indirect network connections to other network services. The user connects to the proxy server, and then requests a connection, file, or other resource available on a different server. The proxy provides the resource either by connecting to the specified server or by serving it from a cache.
In an Internet enterprise a proxy server holds the most commonly accessed and recently used content from the World Wide Web in order to provide quicker downloads for users and to increase server security; proxy servers can store millions of pages from the Web. It is common for an Internet Service Provider to use a proxy server. Proxy servers are also structured to allow direct Internet access from behind a firewall. They open a socket on the server and allow communication via that socket to the Internet.

Web Browsers Compatible with Proxy Servers

• Windows – Netscape 6.x and later, Internet Explorer, Mozilla, Opera
• Macintosh (OS 8.x-10.x) – Netscape 6.x and later, Mozilla, Safari
• UNIX – Netscape 4.51 and later, Mozilla

Configuring Proxy Servers

Netscape/Mozilla

1. Open Netscape/Mozilla
2. Click on Edit
3. On Macs running OS 10.x, click on Mozilla or Netscape at the top of the screen
4. Click on Preferences
5. In the list on the left, click on the arrow next to Advanced
6. Click on Proxies
7. Click on the radio button next to Automatic proxy configuration URL
8. Enter http://proxy.rice.edu/proxy.pac into the field next to that radio button

Internet Explorer

1. Open Internet Explorer
2. Click on Tools
3. Click on Internet Options
4. Click on Connections
5. Click on the LAN Settings button
6. Make sure that the checkbox next to Use automatic configuration script is checked
7. In the Address box, type the IP address of the proxy server.

Opera

1. Click on File
2. Click on Preferences
3. Select Network from the list to the left
4. Click on the Proxy Servers button
5. Select the checkbox next to Use automatic proxy configuration
6. In the field under the Use automatic proxy configuration checkbox enter the IP Address of the proxy server.

Safari

1. Start Safari
2. From the Safari menu, choose Preferences.
3. Click the Advanced tab icon.
4. Click the Change Settings button in the proxy field. The Network window will appear.
5. Look for the Show drop-down box and choose the network to configure—AirPort, Built-in Ethernet, or Modem.
6. Select Proxies from the Configure Proxies field.
7. In the Select a proxy server to configure field, check the Automatic Proxy Configuration box.
8. Enter the IP Address of the proxy server being used.
9. Click Apply Now.
10. Close the Network window.
11. Close the Advanced window.