I have written about configuring Firefox for increased security, now it's time to talk about increasing privacy. Some of these ideas will also have a positive impact on your security as well. I'm not going to get into ways to can keep your wife from knowing where you've been on the Internet. I'm more concerned about maintaining your privacy with regard to Web site operators.
Cookies have a lot to do with your privacy on the Web. Using cookies, Web site operators can tell how you move around their Web sites and how loyal you are. They are also critical for the proper function of most Web applications. For this reason, I do not recommend denying all cookies. Here are some tips with regard to cookies:
- You don't need to accept all cookies. By configuring Firefox to deny cookies from ad farms (e.g., doubleclick.net) and off-site analytics applications (e.g., Google Analytics) you can continue to use Web sites without providing too much information to third-parties. The easiest way to identify these cookies is to set your browser to ask you before accepting cookies. Navigate to your browser preferences, click on the Privacy tab. In the Cookies box, tell Firefox to keep until: "ask me every time". You won't want to leave it this way forever, but doing it for a week will help you get a sense of what's going on. While your browser is asking you to decide you can choose to block the cookies that look like they're from ad farms and analytics applications. When you've had enough, change the setting back.
- You don't need to keep cookies around for multiple sessions either. This is particularly helpful on machines that are shared by multiple people. The simplest thing to do here is to configure Firefox to delete all your cookies when you close your browser. Navigate to your browser preferences, click on the Privacy tab. In the Cookies box, tell Firefox to keep until: "I close Firefox". Doing this will ensure that you get a new cookie the next time you visit a site. This will limit their ability to tell if you're a return visitor until you log in. It will also keep other users of the computer out of your Web accounts that keep you logged in by using a cookie, regardless of whether you've restarted Firefox.
- If you are paranoid about other users of your computer then you might want to consider disabling form autofill. This is clearly a trade-off of privacy/security over and against ease of use. To do this Navigate to your browser preferences, click on the Privacy tab. In the History box, tell Firefox to not to "Remember what I enter in forms and the search bar". This will ensure that Firefox will not remember your credit card number and other data entered into forms.
These simple changes can help you keep a lower profile while surfing the Web.