Chapter 15 Unified Threat Management for FortiOS 5.0 : Application control : Application control concepts
  
Application control concepts
You can control network traffic generally by the source or destination address, or by the port, the quantity or similar attributes of the traffic itself in the security policy. If you want to control the flow of traffic from a specific application, these methods may not be sufficient to precisely define the traffic. To address this problem, the application control feature examines the traffic itself for signatures unique to the application generating it. Application control does not require knowledge of any server addresses or ports. The FortiGate unit includes signatures for over 1000 applications, services, and protocols.
Updated and new application signatures are delivered to your FortiGate unit as part of your FortiGuard Application Control Service subscription. Fortinet is constantly increasing the number of applications that application control can detect by adding applications to the FortiGuard Application Control Database. Because intrusion protection protocol decoders are used for application control, the application control database is part of the FortiGuard Intrusion Protection System Database and both of these databases have the same version number.
To view the version of the application control database installed on your FortiGate unit, go to the License Information dashboard widget and find the IPS Definitions version.
To see the complete list of applications supported by FortiGuard Application Control go to the FortiGuard Application Control List. This web page lists all of the supported applications. You can select any application name to see details about the application.