Aastra Telecom 41-001343-02 Incoming Intercom Calls, Microphone Mute, Delay before Auto-Answer

Operational Features

Note:

To configure outgoing intercom calls using these parameters, see “Configuring Intercom Calls Settings” on page 5-81.

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 con- figuration. 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 fea- ture.

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 enabled, 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 follow- ing:

•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 intercom 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 parameter (0 = disable in the configuration files), and there is an active call, the phone treats an incoming intercom call like a normal 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:

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

5-80 41-001343-02 REV04 – 05.2014