CUPS
This signature detects Common Unix Printing System (CUPS), which is a computer printing system for Unix-like operating systems. It uses IPP as the basis for managing print jobs and queues. The CUPS daemon listens for IPP requests on UDP port 631.
Available to all SRX running 12.3X48+
Available to all MX running 20.2R1+
Available to all vSRX running 20.3R1+