Privacy Watch: Free Tool Makes You Anonymous on the Web

Illustration: Mark Matcho

No matter how meticulously you remove cookies and cleanse spyware and adware from your PC, snoops can still track your movements on the Web. The telltale sign is your IP address.
For a Web server to send your browser information, the server needs to know that you're at 192.168.234.10, for instance. Some Web servers can reveal the city you're in, the Internet service provider you use (or the company you work for), and the type of connection you have--in other words, a lot more than a cookie ever could.

Fortunately, a free tool named Tor from Electronic Frontier Foundation can close this privacy loophole. Tor--a World Class Award winner last month, and available at tor.eff.org--strips the identifying IP address from the headers of each data packet that leaves your computer, by bouncing the packet through a special network of computers called "onion routers." The trade-off for this kind of anonymity, of course, is the speed of your Web browsing. Bouncing from server to server takes time. Tor's advantage over previous anonymizing services is that it can anonymize more than browser communications. Tor works with apps like Thunderbird, Outlook, and Eudora--and with IM programs.

Before you can use Tor, you must download a small freeware app called Privoxy). After installing Privoxy, you must alter a line in one of the program's settings files so that Privoxy can talk to Tor (click here for instructions).

Without directions to send their data through Tor, your apps won't know how to transmit packets over the network. In Internet Explorer, click Tools, Internet Options, then the Connections tab, and then the LAN Settings button. Check Use proxy server for your LAN and click Advanced. In the HTTP field, type localhost; and in the Port field, enter 8118. In Firefox, go to Tools and click Options. Click Connection Settings, and in the field labeled 'HTTP Proxy' fill in the same information as outlined above for IE.

You'll have to enter these proxy settings into each app you want to use with Tor, and you'll lose a little extra time to Web browsing each day. But if you want complete privacy, it's a small price to pay.
--Andrew Brandt