Enhancing Online Privacy by Managing Cookies
is a small text file that’s stored on your computer. Websites use them
to “remember” information about your session at that site: shopping
cart data, page customizations, usernames, passwords, and so on.
other site can access your cookies, so they’re generally safe and
private under most—but definitely not all—circumstances. To understand
why cookies can sometimes compromise your privacy, you have to
understand the different cookie types that exist:
This type of cookie lives just as long as you have Internet Explorer
running. Internet Explorer deletes all temporary cookies when you shut
down the program.
This type of cookie remains on your hard disk through multiple Internet
Explorer sessions. The cookie’s duration depends on how it’s set up,
but it can be anything from a few seconds to a few years.
First-party cookie— This is a cookie set by the website you’re viewing.
This is a cookie set by a site other than the one you’re viewing.
Advertisers that have placed an ad on the site you’re viewing create
and store most third-party cookies.
These cookie types can compromise your privacy in two ways:
A site might store personally identifiable information—your
name, email address, home address, phone number, and so on—in a
persistent first- or third-party cookie and then use that information
in some way (such as filling in a form) without your consent.
site might store information about you in a persistent third-party
cookie and then use that cookie to track your online movements and
activities. The advertiser can do this because it might have (for
example) an ad on dozens or hundreds of websites, and that ad is the
mechanism that enables the site to set and read their cookies. Such
sites are supposed to come up with privacy policies stating that they won’t engage in surreptitious monitoring of users, they won’t sell user data, and so on.
help you handle these scenarios, Internet Explorer implements a privacy
feature that gives you extra control over whether sites can store
cookies on your machine. To check out this feature, select Internet
Explorer’s Tools, Internet Options command, and then display the
Privacy tab, shown in Figure 4. You set your cookie privacy level by using the slider in the Settings group.
Figure 4. In the Internet Options dialog box, use the Privacy tab to manage your cookies.
You set your cookie privacy level by using the slider in the Settings group. First, let’s look at the two extreme settings:
Accept All Cookies— This setting (at the bottom of the slider) tells Internet Explorer to accept all requests to set and read cookies.
Block All Cookies— This setting (at the top of the slider) tells Internet Explorer to reject all requests to set and read cookies.
all cookies might sound like the easiest way to maximize your online
privacy. However, many sites rely on cookies to operate properly, so if
you block all cookies you might find that your web surfing isn’t as
convenient or as smooth as it used to be.
In between are four settings that offer more detailed control. Table 1 shows you how each setting affects the three types of privacy issues.
Table 1. Cookie Settings and Their Effect on Surfing Privacy
|Medium||Blocked||Blocked (implicit)||Restricted (implicit)|
|Medium High||Blocked||Blocked (explicit)||Blocked (implicit)|
|High||Blocked||Blocked (explicit)||Blocked (explicit)|
Here are some notes about the terminology in this table:
Restricted means that Internet Explorer doesn’t allow the site to set a persistent cookie, just a temporary one.
along with the cookie and that can be read by the browser.
means that one or more pages leading up to the cookie warned you that
your personally identifiable information would be used and you agreed
that it was okay.
means that the page that reads the cookie warned you that your
personally identifiable information would be used and you agreed that
it was okay.
you decide to change the privacy setting, you should first delete all
your cookies because the new setting won’t apply to any cookies already
on your computer. See “Deleting Your Browser History,” earlier in this chapter.
fine on a broad level, but you can fine-tune your cookie management by
preventing specific sites from adding cookies to your computer. For
example, you can prevent Google from tracking your search activity by
preventing it from adding cookies to your PC. You might also want to
block ad sites such as doubleclick.net.
Here are the steps to follow in Internet Explorer to block a site from adding cookies:
Select Tools, Internet Options.
Display the Privacy tab.
Use the Address of Website text box to type the site domain.
Repeat steps 4 and 5 to add all the sites you want blocked.
Click OK in the open dialog boxes.