ATT System 25 Reference Manual

							FEATURES AND SERVICES
SYSTEM 25
PART OF
CABINET
OCTOPUS     PART OFCABLE
SIP
ZTN130C2
CPU/MEMZ210AADAPT.C1355AFADAPT.C3
Z3A4ADU
C1
CALLACCOUNTING
SYSTEMPART OF
SIPC4Z3A1OR Z3A4C1W1B1858A 400B2ADU
ADAPT.
(NOTE)
C7
2012DTRANS.248BADAPT.LEGEND:
B1- TYPICAL-103A CONNECTION BLOCK*
C1- MODULAR CORD (D8W-87) - PEC 2725-07G
C2- OCTOPUS CABLE (WP90780) - PEC 2720-05PW1 -4-PAIR INSIDE WIRING CABLE*
Z3A1 ADU -EQUIPPED WITH 3-FOOT PLUG-ENDED EIACORD - PEC 2169-001
Z3A4 ADU- EQUIPPED WITH 3-FOOT RECEPTACLE-ENDED EIA
CORD - PEC 2169-004
C3 - EIA CROSSOVER CABLE (M7U-87)
C4 - ADU CROSSOVER CABLE (D8AM-87)
355AF ADAPTER- RS-232 RECEPTACLE TO MODULAR JACK
Z3A4 ADU - EQUIPPED WITH 3-FOOT RECEPTACLE-ENDED EIA CORD
C1 -MODULAR CORDS (2) (D8W-87)
PEC 62515
C7 - MODULAR POWER CORD (D6AP-87)
248B ADAPTER -
MODULARIZES 2012D TRANSFORMER400B2 ADAPTER - POWER ADAPTER
2012D TRANSFORMER - 15-18V AC SOURCE
NOTE: CAS MODEL 200 REQUIRES Z3A4 ADU.
*- FURNISHED BY INSTALLER
Figure 2-12.Call Accounting System—On-Premises Direct Connections (Greater Than
50 Feet From System Cabinet or Not Sharing Same AC Outlet)
2-80 
						

							Callback Queuing
Callback Queuing
Description
This 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.
Callback Queuing puts inside calls to busy stations and trunk pools 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 the 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
directs the longest waiting call to the facility and signals its originator that the call is being
completed.
Each station can activate Callback Queuing manually or can be administered for automatic
activation of inside calls only, outside calls only, or 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.
Inside Calls
An inside station is considered busy if all its System Access (SA) buttons are in use (multlline
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, and the call goes into queue.
l Manual Queuing
A single-line terminal user activates manual queuing by flashing the switchhook to
get recall dial tone and then dialing the callback access code #60. A multiline user
presses RECALL to manually queue for 
a busy station. Queuing tone is returned if
the call can be queued; if not, reorder tone is heard, and the caller must try again
later.
l Automatic Queuing
When the user of a single-line or multiline terminal administered for this option calls a
busy station, queuing tone is returned immediately. If maximum queue size has been
reached, the caller gets busy tone and must try again later.
l Off-Hook Queuing
After a call has queued for a busy station, the caller can wait off-hook for the
connection to be completed. The caller hears dequeuing tone (three short beeps)
when the queued-for station becomes available and then ringback as the station is
being rung.
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							FEATURES AND SERVICES
While off-hook on a queued call, a single-line user can transfer or conference the
call.
l On-Hook Queuing
The caller can hang up after a call to a busy station goes into queue. The call retains
an association with the on-hook calling terminal, and a callback will alert the on-hook
user when the queued-for station is available.After a single-line terminal user goes
on-hook, the queued call cannot be accessed until a callback attempt occurs. During
the waiting period, the single-line user can place or receive other calls.
When a multiline user hangs up after a call is queued, the green status LED of the
queued System Access (SA) button winks, as if the call is on hold. If the user goes
off-hook and presses the button while the call is still queued, the LED lights steadily
and queuing tone is heard again.While waiting for a queued call, the user can place
and receive other calls.
l Callback
Callback applies only to stations that went on-hook after queuing was activated.
When the queued-for station becomes available to receive a queued call, the system
sends repeated priority ringing to the on-hook calling station. At a multiline set,
callback rings at the same SA button where the call to the queued-for station was
originally placed; the winking status LED of the button changes to flashing. The on-
hook station continues to get priority ringing until the callback is answered or until
the administered number of callback rings has been reached. When the original
calling station answers the callback, dequeuing tone is heard; this indicates that the
queued-for station will now be rung.The calling user hears ringback until the
queued-for station answers.
An off-hook single-line set cannot receive callback until it is on-hook again. If a
multiline set is off-hook and active on another call when callback arrives, it receives
one cycle of priority ringing.
Administration sets the maximum number of callback attempts and the number of
rings per attempt. Each time a callback attempt for a given call is not answered, it is
counted against the assigned number.If the last allowed callback goes unanswered,
the system cancels the queued call.
If a queued-for station becomes busy during callback and the calling station answers,
queuing tone is heard, not dequeuing; this callback attempt does not count against
the administered number. Another special situation exists when a multiline station
fails to answer a callback before ringing stops and the queued-for station remains
idle during the interval before another attempt. The multiline station can go off-hook
between callback attempts, press the queued button, and ring the idle queued-for
station.
2-82 
						

							Callback Queuing
l Callback Cancellation
The user can cancel a call that was queued manually or automatically. At a multiline
set, if the call is queued off-hook, the user presses the DROP button, then the
queued call button.If the call is queued on-hook, the user must go off-hook, press
the queued call button to become active on the call, press DROP, and then press the
queued call button again.
At a single-line set, the user must get dial tone, then dial the callback cancel access
code #61.
The attendant at a Switched Loop Attendant Console cancels a queued call by
becoming active on the queued call LOOP button and pressing DROP.
Outside Calls
Only trunk pools can be queued for, not individual trunks.Queuing for trunk pools is similar
to queuing for inside stations except for the tones received and the methods of placing calls.
To be eligible for queuing when not using ARS, a trunk pool must have all of its members
administered to be queuable by dial access users.To make an outside call, the user dials
the access code of the pooled facility, then, after second dial tone, the rest of the desired
outside number. The dialing must be terminated by pressing # or by waiting for timeout. If
all trunks are busy, and the calling station is administered for automatic queuing for outside
calls, queuing tone is returned to the caller. (Note that dialing the complete outside number
is required, even if all trunks are busy; this ensures that no redialing is necessary on the
queued call.)
If automatic queuing is not administered, the caller hears reorder tone but can queue the call
by the appropriate manual method.Reorder tone is also returned if the busy trunks are not
administered for dial-access queuing or if all the queue slots are in use. In these cases,
queuing cannot take place.
Callback Reservations
When busy facilities are called, both queue slots and queued-for stations are “reserved”
before they are actually “seized” by the calling stations.Reservation of queue slots applies
only to manual queuing, in which the caller has a choice of activating callback queuing, or
not, after hearing busy tone.It ensures that callers can elect to queue in the same order that
they get busy tone, not in the order that they press RECALL or dial #60. If a caller reserves
or seizes the last available queue slot, new callers will not be able to queue.
Reservation of stations means that the system marks stations busy to new calls until all their
callbacks have been attempted. Even if a SA button (or a single-line set, which is equivalent
to a SA button) is idle, it cannot receive a call while callback attempts remain. However, the
station user can place calls.
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							FEATURES AND SERVICES
Considerations
Callback Queuing saves time for users because they can avoid repeated redialing of busy
numbers. It 
allows trunks to be used more efficiently and can reduce the number of trunks
required for a system.
The feature is similar to the Busy-to-Idle Reminder feature but applies to different types of
calls. The two features can both be used to reduce redialing effort.
A single-line voice terminal can queue only one call at a time.
Calls originated by using Personal Line, Direct Facility Access, and Direct Station Selection
buttons cannot be queued.
On calls to busy facilities,Callback Queuing occurs only after Coverage, Following,
Forwarding, and Hunting have been attempted.
Interactions
The following features interact with Callback Queuing.
Account Code Entry: An account code entered before queuing is saved for SMDR.
Attendant Camp-On: Trunk calls camped onto a station by an attendant are given priority
over queued calls. Multiple camp-on calls are allowed per station.
Attendant Direct Extension Selection: Callbacks to the attendant do not flash at the
associated Selector Console.
Attendant Positions: The attendant can queue calls that are extended using the normal
START-RELEASE button operation.However, calls originated using only the START button
(no other call put on hold) cannot be queued.
Attendant Message Waiting: An attendant active on a queued inside call can toggle the
MESSAGE LED of the queued-for station by pressing the ATTENDANT MESSAGE WAITING
button.
Automatic Route Selection (ARS): Implementation of Callback Queuing affects ARS in three
respects:
l On-hook ARS queuing is allowed.
l Callback Queuing and ARS share a common queue, which has a capacity of 64 calls.
l When a station without automatic queuing originates an ARS call, the caller hears
reorder tone if all routes are busy; the call can then be queued manually.
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							Callback Queuing
Bridging of System Access Buttons:Calls originated on Bridged Access (BA) buttons can
be queued. On callback attempts, only the originator will be rung; all other appearances will
only flash. Any appearance in the bridging arrangement can be used to drop a queued call,
if no other station is off-hook.
If both principal and bridging users are off-hook on a call to a busy facility, only the first one
off-hook can queue the call.
Call Accountability: Any call accountability information entered before activation of queuing
is saved for SMDR.
Call Waiting: If a station with automatic queuing calls a busy station with Call Waiting, the
calling station hears queuing tone, not special ringback; also, the called party does not hear
Call Waiting tone.Call Waiting tone is heard only when special ringback is returned to the
caller. A station without automatic queuing gets special ringback but can manually queue the
call.
If the queued-for station dials the Call Waiting pickup code V 9, the first off-hook queued or
waiting call will be dequeued.
Conference: 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.
Coverage: Callback calls to the originator do not send ring signals to its coverage stations.
If a call is queued for a station, then one of the coverage stations becomes available, the call
remains queued for the originally-dialed station.
Data/Pooled Modem: Calls to busy data ports can be queued. Data ports cannot queue
calls or receive call waiting treatment. A call requiring a pooled modem cannot queue.
Direct Group Calling (DGC): Inside calls to busy DGC groups can be queued. Queuing is
not allowed if all members of the DGC group are logged out. A multiline DGC member with a
queued call and a single-line member with an off-hook queued call are considered busy.
Display: Before Callback Queuing is invoked, the display shows the standard format for
origination of an inside or outside call.When Callback Queuing goes into effect for the call,
the display updates to CALL QUEUED. If the user cancels queuing, the display is QUEUE
CANCELED. If the queuing attempt is denied, QUEUE DENIED appears.
When a station receives callback, indicating that the called facility is now available, the
display shows the same information seen before queuing, except that queue descriptor Q
appears in position 1, displacing the number and name fields to the right. Once the user
answers the callback, the display updates to standard origination format; Q is removed.
If a user with Automatic Incoming Call ID is off-hook when a callback attempt is made, the
display will not flash the callback call’s information. However, this information is accessible
via the Inspection feature.
Drop Button: If the user is off-hook on the queued call button, pressing the DROP button
and then the queued call button cancels the call.
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							FEATURES AND SERVICES
Exclusion: pressing the EXCLUSlON button does not drop a queued call. The EXCLUSION
button’s status LED tracks the status LED of the associated button. For example, on a
callback attempt, the EXCLUSION LED will also change from winking to flashing. If the
EXCLUSION button is tracking a conference on hold, it will stay winking with the rest of the
conference. When the callback attempt is answered. the EXCLUSION LED lights steadily to
track all the conference buttons.
Following/Forwarding: Calls that forward or follow are queued on the busy “away” station.
not the “home” station.
Callback attempts to the originator do not follow or forward.
Hands-Free Answer on Intercom (HFAI): Callback calls to the originator do not receive HFAI
treatment.
Hunting: If all stations of a hunt group are busy, the call queues only for the dialed station in
the group.
Leave Word Calling: A user who is queued for access to a busy station can invoke Leave
Word Calling (LWC). The callback request is canceled when LWC is activated.
Park: Queued calls cannot be parked unless they are part of a conference. Reorder tone is
returned whenever an illegal park is attempted, but the queued call is not disconnected. If
parked conference members drop out, Ieaving only a queued call, it will be disconnected to
prevent the illegal condition of a single queued call being parked.
Pickup: A callback call cannot be picked up.
Recall/Centrex: The RECALL button can still be used to send switchhook flash to Centrex
trunks. If a conference exists with a queuable tone and a Centrex trunk, the first push of
RECALL queues a call. A second push of RECALL is needed to send switchhook flash.
Selector Console: Callbacks to the attendant do not flash on the Selector Console.
Send All Calls: Callback attempts to the originator are not affected by Send All Calls.
Transfer: 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.).
Administration Requirements
System:
l Assign the maximum queue size for inside calls (0 to 64; default = 64).
l Assign the maximum queue size for outside calls (0 to 64; default = 64).
2-86 
						

							Callbaok Queuing
Note: It is highly recommended that queue size be set to either 0 or 64, not to some number
in between.
l Assign the minimum time between callback attempts for inside calls (0 to 120 seconds;
default = 30).
l Assign the minimum time between callback attempts for outside calls (0 to 120 seconds;
default = 30).
Voice Terminal Ports: (Every station has independent control of the number of callback retries and
the number of rings per attempt.)
l Assign the number of callback retries for inside calls (0 to 15; default = 2).
l Assign the number of callback retries for outside calls (0 to 15; default = 2).
l Assign the number of rings per callback attempt for inside calls (2 to 15; default = 3).
l Assign the number of rings per callback attempt for outside calls (2 to 15; default = 3).
l Allow automatic queuing for inside calls (yes or no; default= no).
l Allow automatic queuing for outside calls (yes or no; default = yes).
Trunk Ports:
l Allow queuing of dial access calls (yes or no; default= no).
November 1995
2-87 
						

							Features and Services
Calling Restrictions
Description
Designated voice and data terminals can be restricted from making certain types of calls. Available
restrictions are:
l Outward Restriction
l Toll Restriction
l Facility Access Restriction
l ARS Restrictions
l Public Station Restrictions
l International Restrictions.
l Interexchange Carrier (IXC) Restrictions
Note: Each of these restrictions is voice terminal oriented, not PDC oriented.
Outward Restriction:
When outward restricted, a station will be unable to place any outside calls. The station will be able
to answer incoming calls and place and receive inside calls. A station that is outward restricted will
be unable to use Automatic Route Selection to place external calls except to the emergency
numbers.
Toll Restriction:
Allows calls by restricted terminals to be made based on as many as the first six digits of the
number called (after the facility access code). Toll restricted stations can make outgoing calls only
to those numbers that are on the Toll Call Allowed (TCA) Lists to which they have access. TCA
entries must be in the form AAA or NAA-XXX (exactly three or six characters). The system
administrator can establish up to 5 individual lists. A list can contain from 1 to 164 entries, provided
that the total of all five lists does not exceed 164. One character“.” can be specified as a wild card
character in place of the last 1, 2, 3, 4, or 5 digits (e.g., “NA.”, “N..”, “N.....”, etc.). When this
character is used, any digit in the dialed number appearing in that position is acceptable. Those
stations assigned Toll Restriction Class 1 have access to all five TCA Lists; Class 2 stations, just
lists 2 through 5; Class 3 stations, just list 3 through 5; Class 4 stations, just list 4 through 5; and
Class 5 stations, just list 5. To allow calls within a customer’s local area, individual office codes are
entered; this allows the customer to restrict toll calls within the local calling area. NAA-AAA entries
allow specific office codes to be called within an area. Note: NAA-only entries are not permitted
(use NAA-...).
Note that stations that are toll restricted are only toll restricted on CO trunks (type 701 and 801),
when they use the ARS feature, or when a PBX/Centrex trunk and the PBX/Centrex access digit is
dialed. They will not be toll restricted when they dial access (or button access) any other type of
trunk (e.g., FX, WATS, or Tie trunks).
2-88November 1995 
						

							Calling Restrictions
Equal Access:
Allows equal access to all Interexchange Carriers (IXC) when a station is administered for IXC+1
and/or IXC+011 dialing. Toll restriction checking occurs when an IXC code+1 or IXC code+01 is
dialed. IXC code+0, IXC code+011, and 0+ calls are allowed from toll restricted stations that have
outward calling capability and select a type 701 and 801 trunk administered with “Originating Line
Screening” either via pool access or personal line appearance. This service is provided by the Local
Exchange Carrier (LEC) identifying the call as one which should not have the operator bill the
originating facility.
International Restriction:
International dial codes entered in the Toll Allowed List are treated as DISALLOWED entries rather
than ALLOWED entries. The international entries have the form “0ABCDE” (6 digits always with a
leading zero), where ABCDE can be any digit ranging from 0-9 or “.”, which is a wild card. If 0 + 5
dots are entered in a Toll Disallowed List, the station(s) assigned to that class cannot make
international calls. If a station is in Class 1, only Class 1 entries will block a call; if a station is in
Class 2, Class 1 and 2 entries will block; if in Class 3, Class 1, 2, and 3 will block; etc.
November 19952-88a