Web proxies

You may wish to configure your Web browser to use a proxy. Using a proxy provides a small increase in privacy, because your real IP address will not appear in server logs, but many other bits of identifying information, such as cookies and user-agent strings (which give your browser and OS version) are still passed through. In addition, the proxies act as caches, storing recently-accessed Web content closer to you, which may help when accessing some slow Web sites. (It can only do this if the originating server permits it to do so; dynamic content like webmail or bulletin boards will not see any benefit.)

Here at CSAIL, the principal value of the proxy for most users is the ability to access online resources that are restricted to MIT IP addresses. Many such resources still haven't updated their systems to recognize that CSAIL has its own IP address space; because the proxy has a MITnet ("net 18") address, it is able to access these resources on your behalf.

These proxies are accessible only from CSAIL networks. If you need to access these resources from off-campus, you could use MIT's VPN: http://vpn.mit.edu/ or (for some sites) the MIT Libraries' certificate-authenticated proxy.

Configuration instructions for Firefox (version 2 or 3, including Iceweasel)

  • Open Firefox's Preferences, aka Options, panel: Tools/Options (Win), Firefox/Preferences (Mac), Edit/Preferences (Linux)
  • Click the Advanced tab, then Network subtab. Under Connection, click Settings...
  • Select the radio button labeled "Manual proxy configuration", and check the box "Use the same proxy for all protocols".
  • For "HTTP Proxy", enter squid.csail.mit.edu and port 3128.
  • Under "No Proxy for", enter (there's no sense in using the proxy for hosts that are closer to you than the proxy is).
  • Then click "OK" twice to save your settings.

Configuration instructions for Internet Explorer (and Opera/Win)

  • From the menu bar, go to Tools => Internet Options.
  • Select the "Connections" tab at the top. Click on the "LAN Settings..." button; this will pop up another window with your proxy configuration.
  • Check the box "Use a proxy server for your LAN"; enter squid.csail.mit.edu for "Address" and 3128 for "Port". Also check the box "Bypass proxy server for local addresses".
  • Click Advanced. Under "Exceptions", enter 128.30.*.*;128.31.*.*;*.csail.mit.edu
  • Then click "OK" three times to save your settings.

Configuration instructions for Safari (and Opera/Mac)

  • Under the Apple menu, choose System Preferences. Click "Network".
  • If items are greyed out, unlock the preference pane by clicking the lock icon and entering a local administrator password (likely your own)
  • Click Ethernet, then Advanced. Click the Proxies tab.
  • Check "Web Proxy (HTTP)". Enter server squid.csail.mit.edu with port 3128
  • Check "Exclude simple hostnames". Under "Bypass proxy settings for...", add ""
  • Click OK, then Apply. Quit System Preferences.

Please note: the Safari instructions above create settings would need to be repeated for each additional network interface you use to access the CSAIL network. However, if the machine you're using generally stays put at CSAIL as it should be if you're using this service, you'll be best served only using a stable Ethernet connection anyhow.

-- NoahMeyerhans - 29 Mar 2005
-- GarrettWollman - 14 Jun 2005
-- ArthurProkosch - 06 Oct 2008
Topic revision: 29 May 2013, JasonDorfman

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