Many modern applications are hard to block by using the port number as they are designed to avoid blocking (for example, by scanning and using any of the available open ports). Untangle Application Control deeply inspects the packets to identify the used protocol/application.
Untangle offers two versions of Application Control: the free Lite version, which is based on L7-Filter Open project, and the paid version, which is based on the PROCERA networks Network Application Visibility Library (NAVL) technology.
Note
While Untangle Application Control provides the ability to block websites, the best way to block websites is still through Web Filter. Using Application Control to block websites might not be sufficient for you.
The Lite version of the Application Control version is signature based; the signatures are regular expressions (see more on http://en.wikipedia.org/wiki/Regular_expression and http://www.regular-expressions.info/tutorial...