The term "dark web" denotes in part those sites that actively seek to circumvent filtering technology that would identify their content or its source. This is typically done to allow the sites to bypass corporate security measures designed to keep employees on the job and away from surfing porn or other non-work related websites, such as Twitter and other popular social networks, which eat up an increasing amount of work time and open companies to sexual harassment lawsuits and other problems beyond lower worker productivity.
In practice, the stealth techniques used by dark website creators are the anti-thesis to the adult industry supported RTA label, which clearly identifies a website as being adult in nature and thus not suitable for children or other inappropriate audiences, including those in the workplace.
In some cases, dark web usage is not about what the website owner does, but is about what the surfer does; namely through accessing inappropriate websites using proxy servers to mask their online movements while at the workplace.
"The dark web is about corporate users' inability to see how workers are using the web," said Cisco Product Line Manager Kevin Kennedy. "It is that dark, dynamic and churning part of the web that has created the problem for business."
Oftentimes filtering systems rely heavily on blacklists and whitelists of banned and trusted websites, but according to Cisco, a practice known as churning is employed by some website operators, where URLs and IP addresses are continually changed in order to evade blacklist blocking.
"It's happening and businesses don't necessarily see it," Kennedy said. "Most people are pretty well behaved at work, but some are not."
"Using an anonymous proxy is sophisticated to us," he added, "but the kids that have graduated from colleges in the past five years are very aware of using software to get to proxies."
As for the severity of the problem, an estimated 80 percent of the more than 45 billion websites now online are ineffectively handled by filtering programs, in part due to the poor categorization of user-generated content pages.
"Legacy approaches only give a small view now that there is this explosion of user-generated content online," Kennedy said. "We as an industry have to do better at how we solve this problem."
IronPort Web Usage Controls are able to identify proxy servers and are reportedly 50 percent more effective than previous generation filters. The software does this by going beyond list based processes to actually scanning the page in realtime using a dynamic engine to uncover inappropriate content.
"You have to balance between catch rate and false-positive rate," Kennedy concluded, referring to those instances that a filter erroneously blocks an acceptable website.
