AT&T MERLIN LEGEND Release 4.0 Feature Reference page 106

Feature Reference
Considerations and Constraints
General
A user must subscribe to the Caller ID service in order for incoming calls
through the 800 GS/LS-ID port module to receive Caller ID information
(loop-start lines only).
Caller ID/PRI ANI Comparison
Caller ID information arrives between the first and second ring at an extension.
PRI ANI uses the second screen of the telephone display to show the called
party number, while Caller ID generally uses this page to display the facility
number.
Feature Interactions
Conference
Displays
Do Not Disturb
Forward/Follow Me
Group Calling
Headset Auto
Answer
Night Service
Pools
Remote Access
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Caller ID
The number of participants is shown on Line 1 of the display. The
conference originator can view call information associated of any
participant by pressing the Inspct button and the button the caller is on.
is displayed if the call is answered before the Caller ID
data arrives. Calling Party Number information appears in the PRI ANI
format. However, outgoing calling information is not displayed.
Caller ID information is not displayed if the user turns on Do Not Disturb.
If the user turns on Do Not Disturb while receiving Caller ID information,
the information remains on the display.
The systemwide LS-ID delay, if programmed, is in addition to the
Forwarding Delay. The total delay is the LS-ID delay plus the
Forwarding Delay.
Caller ID information appears on the display. Outgoing call information
is not displayed.
When using Headset Auto Answer, program the LS-ID Delay option to
avoid loss of Caller ID information.
Caller ID information appears on the display whether or not Night
Service has been activated.
Collisions are avoided on 2-way trunks. Trunks programmed with the
LS-ID Delay option are not seized from a pool for outgoing calls if a call
is coming in on that trunk.
Caller ID information is not retrieved on remote access trunks unless
LS-ID Delay is programmed for the trunk because the calls are
answered too quickly.