Callback Request (Callback Queuing) 2 - 1 - AT&T SYSTEM 25 Manual

Callback Request (Callback Queuing)
The Callback Request (Callback Queuing) feature provides System 25 users with a simple way
to complete calls to busy facilities (stations or trunk groups), without having to manually
repeat the calling procedures. This feature saves time for users because they can avoid
repeated dialing of busy numbers. It also allows trunks to be used more efficiently and can
reduce the number of trunks required for a system.
Callback Queuing puts inside calls to busy stations and trunk groups into a queue. The
maximum number of queue slots is 64, administrable in any combination of inside and
outside calls. After a call is queued for a busy facility, the caller can stay off-hook or go
on-hook. When the queued-for facility becomes free to receive another call, the system
signals the originator of the longest waiting call and completes the call as dialed.
Trunk calls camped onto a station by an attendant are given priority over
NOTE:
queued calls.
Each station can activate Callback Queuing manually or can be administered to have
automatic activation for inside calls only, for outside calls only, or for all calls. Manual
activation is by dial access at single-line sets and by operation of the RECALL button at
multiline sets. Automatic activation, if administered, occurs whenever a busy facility is
called and requires no action by the caller; it can be canceled manually.
A queued call can be part of a conference, unless a Call Waiting call is already part of the
conference. A queued call counts as two conferees until it is completed. Queued calls can
be transferred. Single-line sets can transfer queued calls only before going on-hook. The
transferring station must wait for the transferred-to facility to answer before completing the
transfer; the transferred-to facility then receives queuing tone. Queued calls cannot be
transferred to a tone (ringing, busy, etc.).
Inside Calls
An inside station is considered busy if all of its SYSTEM ACCESS buttons are in use
(multiline sets), if it is off-hook (single-line sets), and if all coverage points are busy. A
call to such a station will receive busy or special ringback tone if the calling station is not
administered for automatic queuing; the caller can then activate queuing manually. If the
calling station has automatic queuing, the caller hears queuing tone (five short beeps)
instead of busy or special ringback tone, and the call goes into queue.
Callback Request (Callback Queuing)
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