S 3.12 Informing all staff members about possible PBX warning notices, warning symbols and acoustic alarm signals

Initiation responsibility: PBX officer; IT Security Management; personnel committee/works council

Implementation responsibility: IT Security Management, Administrators

All staff members should be aware of the meaning of warning notices and/or symbols and acoustic alarms of the PBX (telecommunications facility). In particular, this includes the following:

• attention signal for direct voice calling;

• busy override warning signal (trunk offering tone);

• indication of handsfree operation;

• indication of activated direct voice calling;

• indication of automatic call-back; and

• indication/flash in case of an add-on (three-party) conference.

The use of features which are not officially authorised can be especially crucial to IT security. The warning indicators for these features should be known to all users.

Additional controls:

• Do the staff know what will happen if somebody makes a busy override call?

• Do the staff know what will be indicated visibly and audibly by a direct voice call?

• Is it possible to discern activation of handsfree operation?