enum MtasAsIwInviteHeaderFilterSessionCaseDT

Numeric Enumeration: 0-3 (0=DISABLED_HEADER_FILTER, 1=ENABLED_ON_TERM_TRANSIT_AS, 2=ENABLED_ON_ORIG_AS, 3=ENABLED_ON_ORIG_TERM_TRANSIT_AS)

References from:
MtasAsIw;

0
DISABLED_HEADER_FILTER
Disabling filtering of SIP headers from INVITE message.
1
ENABLED_ON_TERM_TRANSIT_AS
Enabling filtering of SIP headers from INVITE message on Terminating AS (including transit).
2
ENABLED_ON_ORIG_AS
Enabling filtering of SIP headers from INVITE message on Originating AS only.
3
ENABLED_ON_ORIG_TERM_TRANSIT_AS
Enabling filtering of SIP headers from INVITE message on both Terminating AS (including transit) and Originating AS.