Understanding IDP Application Identification

Juniper Networks provides predefined application signatures that detect Transmission Control Protocol (TCP) and User Datagram Protocol (UDP) applications running on nonstandard ports. Identifying these applications allows Intrusion Detection and Prevention (IDP) to apply appropriate attack objects to applications running on nonstandard ports. It also improves performance by narrowing the scope of attack signatures for applications without decoders.

The IDP sensor monitors the network and detects suspicious and anomalous network traffic based on specific rules defined in IDP rulebases. It applies attack objects to traffic based on protocols or applications. Application signatures enable the sensor to identify known and unknown applications running on nonstandard ports and to apply the correct attack objects.

Application signatures are available as part of the security package provided by Juniper Networks. You download predefined application signatures along with the security package updates. You cannot create application signatures. For information on downloading the security package, see Updating the IDP Signature Database Manually Overview.

The application signatures identify an application by matching patterns in the first packet of a session. The IDP sensor matches patterns for both client-to-server and server-to-client sessions.

Application identification is enabled by default and is automatically turned on when you configure the default application in the IDP policy. However, when you specify an application in the policy rule, application identification is disabled and attack objects are applied based on the specified application. This specific application configuration overwrites the automatic identification process. For instructions on specifying applications in policy rules, see Example: Configuring IDP Applications and Services (CLI).

Related Topics