NTA monitors Network Based Application Recognition (NBAR2) traffic. NBAR2 is an application classification system that is used with deep packet inspection technologies to provide better visibility into network traffic.
After you have enabled your devices to export NBAR2 flow records, you can view the Top NBAR2 Applications in summary views and reports.
When the netflow data is captured by NTA, the NBAR2 application classification may be unavailable or unknown to NTA. In this case, you may see one of the following identifiers for applications that are unidentified.
- Unknown — a Cisco application for which there is no classification available from Cisco.
- Unclassified— an application that is not supported or recognized by the NBAR engine on Wireless LAN Controller traffic and is captured as unclassified.
- Unrecognized — an application that NTA is not able to identify based on information in the current NBAR2 database. This will mostly likely happen when NBAR2 is first enabled on a device and it begins sending flows before sending the applications database. This occurrence depends on the interval set in the device settings.
- Remaining traffic — this is a standard label used on NTA charts to represent monitored traffic that is not applicable to any category presented on the chart.
You can monitor NBAR2 applications by switching the view type in the top-right corner of the Top XX Applications widget or from the NetFlow Applications Summary view. For more information about monitoring applications, see Monitor NBAR2 Applications in NTA.