The "Class" AVP

The "Class" Diameter AVP, which is of type OctetString, uses the AVP code "25".

It has the MANDATORY flag, the MAY-ENCRYPT flag.

It is part of the AA-Answer, Re-Auth-Answer, Session-Termination-Request, Session-Termination-Answer, Accounting-Request, Abort-Session-Request, Accounting-Answer, Diameter-EAP-Answer, Re-Auth-Request commands.