The category of the message.
This field identifies the category of the message (Payment Authentication or Non-Payment Authentication). This will be sent in the Authentication Request Message (AReq) sent by the component when SendAuthRequest is called, and in the Results Request Message (RReq) received from the directory server (populated after calling CheckResponse.
Possible values include:
|01 (default)||PA (Payment Authentication)|
|02||NPA (Non-Payment Authentication)|