Since the mid 1990's Network Address Translation (NAT) was designed to alieviate IP address exhustion. Along with this technology came the ability for network administrators to control what outbound ports users could access. Example, for simple web browsing you would open up the HTTP service on port 80. Additionally, the admin could control access to applications on the Internet such as instant messengers and games.
Since then, application developers have worked around these firewall blocks by simply allowing their applications to run over the ports that are open on the firewall (e.g. HTTP). This new approach to "bypassing the firewall" has generated a new technology called application intelligence. With this new technology firewalls are now able to examine the traffic running through these open ports and identify the actual application using it. In turn, this provides the firewall administrator with the ability to allow or deny access to these applications.
In the follow video we walk you through a demonstration of how this technology works at identifying the applications.