Privacy: Issues, Policies, Statements - Methods Of Online Surveillance

METHODS OF ONLINE SURVEILLANCE

Commercial Web sites' early collection of user data generally consisted only of how many hits a particular site received. No method of information gathering existed to build profiles of typical users who frequently visited the site—the very information that helps marketers tailor advertisements and promotions for specific target audiences. But as Internet software and technology became more sophisticated, online information-gathering techniques grew more powerful and precise. Since the mid-1990s traffic-logging systems have routinely provided details about the brand of browser, version number, and available plug-ins that an individual uses, as well as identify sites previously visited and recreating searches the user conducted on a search engine. Web servers record the Internet address of each computer that visits a site, though this does not reveal the personal characteristics of the actual person operating that computer.

Web sites can also identify visitors via "cookies"—small text files that the Web site writes to a user's hard drive. Cookies contain the name of their proprietary Web site and a unique identifier they assign to a user's computer, which is written to the cookie file the first time a person visits the site. On subsequent visits, the Web site reads the cookie and recognizes the user's computer. Only the originating site can read the cookie, which may also store user passwords. Most browsers contain a feature that permits users to disable cookies.

Banner ads are another online information-gathering device. They are controlled by network advertisers, third-party companies that function as intermediaries between advertisers and Web-site companies. Banner ads place and read cookies, just like Web sites. Network advertisers can track users' surfing habits across the Web by placing banner ads on thousands of different Web pages.

Cookies and banner ads can only generate aggregate user profiles, based on the computers used for browsing rather than individual humans users. To collect more user-specific data, some companies permit users to customize their sites. Often they give users an incentive for registering, such as offering access to restricted content, in the hopes of gathering more detailed information about visitors. This helps online merchants fine-tune their profiles of individual users. When users enter personal data required for site registration or online purchases, the company gains access to that information.