18.3.4.4.1. Display in Call State 
If you want to indicate on the display of a subscriber if a call is
encrypted, you must first enable the parameter SECLVDSP in the
AMO ZANDE for the entire system.
CHANGE-ZANDE:TYPE=SECURITY,SECLVDSP=YES;
The SECLVDSP attribute must also be activated in AMO SDAT on
the subscribers where the display is to appear.
CHA-SDAT:STNO=<station number>,TYPE=ATTRIBUTE,AATTR=SECLVDSP;
IMPORTANT:
If you want a display to appear, the parameter
SECLVDSP must be activated in both AMO ZANDE and AMO SDAT. If
the parameter is activated for the first time in ZANDE, a RES-DSSU:PEN,
must be performed manually for each subscriber (if parameter CONT is
set to yes, the phone restart will be executed automatically for each
relevant subscriber).
You can use AMO SDAT, parameter AATTR=SECLVTON to ensure that
the secure station also receives an advisory tone if the call is not
encrypted.
CHANGE-SDAT:STNO=<station number>,TYPE=ATTRIBUTE,AATTR=SECLVTON;