Siemens 50 manual Multi Address Appearance MAA

Multi Address Appearance (MAA)

A telephone is normally associated with a directory number, or, generally, with a SIP AoR. This number is used for placing calls to the associated telephone and for displaying the tele- phone's (user's) identity when placing calls to another party. The number is also used when more than one call appearance is supported due to additional features like call waiting.

The term ‘keyset’ denotes a telephone which is associated with more than one number. This allows a given telephone to act on behalf of other phone numbers, resp. users. Just like with traditional telephony systems, people sometimes refer to lines instead of numbers, hence keyset phones are also referred to as ‘multiline phones’. The main line, i.e. the line/directory number associated with a given physical telephone, is called primary line. All other lines, which can also be handled on other phones, are denoted as secondary lines. Please note that call log and MWI (Message Waiting Indication) are supported only for the primary line, not for secondary lines.

The programmable feature keys are used for handling the lines and their respective call ap- pearances, supported by the associated LEDs reflecting the line/call status. The number of lines that can be configured is depending on the phone model. For OpenStage 60/80, up to 30 lines can be configured. OpenStage 15/20/40 are limited to 18 lines.

This feature can be used for different use cases, for example:

¾Address multiple users at one phone

¾Enhanced call hold scenarios

¾Allow more than two incoming calls at one phone

For some use cases, however, this feature can not be used, for example:

¾MLA. If the line is configured at more than one phone, incoming calls are sent to the last registered device

¾Line status observation. If the same line is configured at more than one phone, the line status is not presented at these phones.

MAA is automatically activated if line keys are configured at the phone. Line key administra- tion is done by the administrator; the user has no influence on these settings. The phone operates as an MAA phone ‘out of the box’. Depending on the administrator settings, the phone will react slightly different in basic user interactions.

Even if only one line key is configured, the phone changes into line presentation mode. The line presentation mode helps the user to keep track of the different line statuses.

Open Communications Principles and Best Practices 24/09/2010, page 12