The Secure Tone
feature can configure a phone to play a secure indication tone when a call is
encrypted. The tone indicates that the call is protected and that confidential
information may be exchanged. The 2-second tone comprises three long beeps. If
the call is protected, the tone begins to play on a protected phone as soon as
the called party answers.
When the call is not
protected, the system plays a nonsecure indication tone, which comprises six
short beeps, on a protected phone.
The secure and
nonsecure indication tones are supported on the following types of calls:
Only callers on
protected phones can hear secure and nonsecure indication tones. Callers on
phones that are not protected cannot hear these tones.
For video calls, the
system plays secure and nonsecure indication tones on protected devices.
- Intracluster to IP-to-IP
- Intercluster protected
- IP-to-Time-Division-Multiplexing (TDM) calls through a protected
MGCP E1 PRI gateway
For video calls,
the user may first hear secure indication tone for the audio portion of the
call and then nonsecure indication tone for overall nonsecure media.
A lock icon that is
displayed on a Cisco Unified IP Phone indicates that the media are encrypted,
but does not indicate that the phone has been configured as a protected device.
However, the lock icon must be present for a protected call to occur.