Cisco launched software that shines light on potentially troublesome websites hidden in what the US computer security firm dubbed the "Dark Web." Cisco IronPort Web Usage Controls promise to identify as much as 90 percent of "egregious" content that has escaped detection by business IT managers and security applications because of its stealthy nature on the Internet.

Tests of Ironport Web Usage Controls reportedly identified 50 percent more off-limits websites than did previous-generation filtering software relying on website address lists. Ironport combines list-based filtering of known websites with a "dynamic engine" that reads Web pages to decide in real time whether content on them is something businesses don't want workers to access on company time. "The Dark Web is about corporate users' inability to see how workers are using the Web," Cisco product line manager Kevin Kennedy told. Computer users are growing increasingly savvy about sidestepping Internet filters, using proxy servers and other techniques to mask which websites they visit while at work, according to Cisco.

For example, if workers log into from an office computer someone in the IT department can typically tell how much time they fritter away at the popular social-networking website. However, if the employee connects to Facebook through any of thousands of proxy websites set up daily all an IT department monitor will see is a nondescript Internet address as the online destination, Kennedy said.
Ironport software is also trained to recognize proxy servers, according to Kennedy.

Blocking porn websites on work computers typically involves using filter software based on lists of known online adult-content locales. Internet porn purveyors have taken to constantly changing URLs, Internet addresses, in a practice referred to as "churning," according to Cisco. Only 20 percent of the more than 45 billion websites in the world are reportedly categorized effectively enough to be used by filtering programs, leaving 80 percent of the Web in the dark.