Network management Toolkit

Protect your privacy when searching online

Tags:
Privacy,
Online,
Search Engine,
Internet

Declan McCullagh CNET News

Published: 10 Aug 2006 16:50 BST

…to delete cookies and even prevent search engines from ever setting them again. (Unfortunately, not all Web browsers offer this option.)

Let's say you're using Google. Add "google.com" to Firefox's list of cookies-not-allowed sites. Be warned: that prevents you from using options such as personalisation or Gmail, which is why you might want to keep another browser such as Opera, Safari or Internet Explorer around to do those things.

If you're really worried, go to Anonymizer.com and sign up for one of its anonymous browsing options (they're primarily for Windows users). Tor is another option. It's a pain, but protecting your privacy may well be worth it.

Excluding Ixquick, what information do other search engines collect?
We surveyed the search engines in February of this year and asked them precisely that question.

The rough overview: given a number of search terms, they can produce a list of people (identified by Internet address or cookie) who searched for a given term. Second, given a collection of Internet addresses, they can produce a list of the terms searched by the user of a given address. That effectively creates an electronic dossier of an individual.

Who can get access to my list of search terms?
Well, prosecutors in criminal cases certainly can. And it's likely that even lawyers in civil cases — divorce attorneys, employers in severance disputes — will eventually demand that Google, Microsoft, Yahoo, AOL and other search engines cough up users' search histories.

Has this happened before?
Almost. A North Carolina man was found guilty of murder in November in part because he Googled the words "neck", "snap", "break" and "hold" before his wife was killed. But those search terms were found on Robert Petrick's computer, not obtained from Google directly.

How are Internet addresses handed out? Do people always have the same one?
It depends. Many DSL and cable modem providers allocate Internet addresses only when they're in use (the methods are called DHCP and PPPoe). Those IP addresses can change frequently.

Other IP addresses tend to be fixed. Faculty and staff members at universities, and employees of corporations, are more likely to have fixed Internet addresses.

AOL Search is a unique case. Because AOL users tend to be logged in when using it, AOL will know who you are — assuming, that is, that you provided accurate information when signing up for its service.

If Google knows I'm connecting from a dynamically assigned Internet address of 192.1.1.1 one day, and 192.2.2.2 the next day and 192.3.3.3 the third, how can it link my queries together to create that dossier?
This is where "cookies" come in. A cookie is simply a device for a Web site to recognise people the next time they return. Google, Yahoo, AOL and Microsoft all set cookies by default. (Microsoft's expire in 2016; Yahoo's in 2010; Google's in 2038. AOL sets a third-party cookie that expires in 2011.)

In the above example, Google.com would set a cookie for whoever's connecting from Internet address 192.1.1.1 the first day, and then figure out that the same Web browser is connecting from 192.2.2.2 and 192.3.3.3 the next two days. If people are logged in to their Google account, this makes the process even easier, of course.

How long do companies keep records of my search terms?
In our survey, Microsoft, Google and Yahoo all said they keep data as long as it's necessary, which could mean forever. Microsoft did add that they are "looking at ways" to provide users with the option to delete their search histories, and Yahoo made a similar statement. It's unclear how long AOL keeps it.