Operational Features
41-001343-02 REV05 – 07.2014
5-82
Incoming Intercom Calls
You can configure how the phone handles incoming intercom calls. You can receive incoming intercom calls whether or
not there are active calls on the phone. The way the phone handles the call depends on the incoming intercom call config-
uration. The following paragraphs describe the configuration parameters for incoming intercom calls.
Microphone Mute
You can mute or unmute the microphone on the IP phone for intercom calls made by the originating caller. If you want to
mute the intercom call, you enable this feature. If you want to unmute (or hear the intercom call), you disable this feature.
Auto-Answer/Play Warning Tone
The auto-answer feature on the IP phone allows you to enable or disable automatic answering for an Intercom call. If
“Auto-Answer” is enabled, the phone automatically answers an incoming intercom call. If “Play Warning Tone” is also ena-
bled, the phone plays a tone to alert the user before answering the intercom call. If “Auto-Answer” is disabled, the phone
treats the incoming intercom call as a normal call.
The IP phone recognizes if an incoming call is an intercom auto-answer call if the SIP INVITE includes one of the following:
•
A “Call-Info” header containing “answer-after=0”.
•
An “Alert-Info” header containing “info=alert-autoanswer”.
•
An “Alert-Info” header containing “Auto Answer” AND the“To” header containing “intercom=true”.
–
When the IP phones recognize this third type of incoming intercom call, the call will automatically be answered and
the call’s audio will be played through the IP phone’s speaker (i.e. the user’s audio preferences will be ignored).
“Delay” before Auto-Answer
The IP Phones include support for the "delay" parameter (in the Alert-Info header, used in conjunction with info=alert-
autoanswer) in order to facilitate auto-answer functionality. When present, the value of the "delay" parameter specifies the
length of time in seconds an IP phone rings before a call is auto-answered. If this value of the "delay" parameter set to 0
(delay=0), then an incoming call is immediately auto-answered. The absence of the parameter is considered as ring for-
ever.
In order for the delay functionality to operate, you must first enable Auto-Answer on the IP Phone.
Allow Barge In
You can configure whether or not the IP phone allows an incoming intercom call to interrupt an active call. The “
sip inter-
com allow barge in”
parameter controls this feature. When you enable the
sip intercom allow barge in
parameter
(1 = enable in the configuration files), which is the default value, an incoming intercom call takes precedence over any
active call, by placing the active call on hold and automatically answering the intercom call. When you disable this param-
eter (0 = disable in the configuration files), and there is an active call, the phone treats an incoming intercom call like a nor-
mal call and plays the call warning tone. You can set this parameter using the configuration files or the Aastra Web UI.
For incoming intercom calls, an administrator or user can configure the following parameters:
Note:
To configure outgoing intercom calls using these parameters, see
“Configuring Intercom Calls Settings”
.
Configuration File Parameters
Web UI Parameters
sip allow auto answer
Auto-Answer
sip intercom mute mic
Microphone Mute
sip intercom warning tone
Play Warning Tone
sip intercom allow barge in
Barge In
Note:
To configure incoming intercom calls using these parameters, see
“Configuring Intercom Calls Settings”
on
.
