Individuals on school and corporate networks eager to circumvent Web-filter gateways in order to access prohibited Web sites are known to be setting up Web-based proxies and use them as a jump-off point. To address this behavior, 8e6 Technologies has introduced ProxyBlocker, a gateway appliance that the company says stops the circumvention trick.

“The ability to create a Web proxy has gone open source, with toolkits like PHProxy available from SourceForge and other places that give you a way to set up a Web page and turn it into a proxy server,” says Gary Ulaner, director of product management at 8e6 Technologies. He noted users are also making use of generally available anonymous proxy sites to achieve the same goal, circumventing the organization’s Web filter.

According to 8e6 Technologies, the ProxyBlocker appliance can identify use of these so-called Web or circumvention proxies through pattern-recognition technologies that don’t rely on the URL. This proxy-blocking technology is also available in 8e6 Technologies’ Internet filter appliance line for URL, instant messaging and peer-to-peer file filtering.

Ulaner said ProxyBlocker is being offered as a stand-alone product to organizations that may have already installed competitors’ Web-filtering products, which may not be capable of proxy-blocking.

ProxyBlocker starts at $2,500 for software, plus $1,500 to $4,000 for hardware.