Palo Alto Networks firewalls automatically
generate a packet capture for sessions that contain an application
that it cannot identify. Typically, the only applications that are
classified as unknown traffic—tcp, udp or non-syn-tcp—are commercially
available applications that do not yet have App-ID signatures, are
internal or custom applications on your network, or potential threats. You
can use these packet captures to gather more context related to
the unknown application or use the information to analyze the traffic
for potential threats. You can also
Manage Custom or Unknown Applications by
controlling them through security policy or by writing a custom
application signature and creating a security rule based on the
custom signature. If the application is a commercial application,
you can submit the packet capture to Palo Alto Networks to have
an App-ID signature created.