ATT System 25 Reference Manual

							FEATURES AND SERVICES
Attendant Return Coverage On Don’t Answer
Description
This feature allows unanswered calls extended by the attendant to be returned to the
attendant for additional service.
Calls that are not answered after a administered number of rings will transfer ringing to the
Return-On-Don’t-Answer (RTN-DA) button on a Direct Trunk Attendant Console (DTAC) or to
a LOOP button on a Switched Loop Attendant Console (SLAC). If the called voice terminal
has Coverage, the counting of rings for return begins only after the coverage station begins
ringing. If the terminal does not have Coverage but does have delayed ringing on System
Access or Bridged Access buttons, the delay interval (administered as an equivalent number
of rings) must expire before counting begins.
When the RTN-DA button is busy, calls will continue to ring at the called station until the
button is idle. If a SLAC is not available to receive the returning call, it stays in the common
queue until it can be serviced.
To answer a returned call at a DTAC, the attendant presses RTN-DA (if not selected by
Ringing Line Preference.) The call can be reextended via the START button or Selector
Console. In either case, the RTN-DA button is idled as soon as the attendant releases.
To answer a returned call at a SLAC, the attendant merely lifts the handset to be connected
to the ringing loop.
Considerations
Attendant Return-Coverage-On-Don’t-Answer allows the attendant to service calls not
answered within a specified number of rings. This provides the calling party better service
and results in fewer lost calls.
Interactions
The following features interact with Attendant Return Coverage on Don’t Answer.
Attendant Console, Direct Trunk: As long as an Attendant Console remains active, the call
will return to the attendant who extended it.
Attendant Console, Switched Loop: A returning call is directed from the common queue to a
LOOP button. In a two-console system, returning calls can be administered to go to the first
attendant, the second attendant, either attendant, or to the specific attendant who originated
the call.
Attendant Direct Extension Selection: If a call to a Floating PDC (FPDC) is returned to the
attendant, the FPDC’s status LED on the Selector Console will flash during ringing and go
dark when the call is answered.
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							Attendant Return Coverage On Don’t Answer
Coverage:
l DTAC only—Whenever a DTAC attendant is a coverage receiver for a particular
coverage group and a call is placed from the attendant position via the Start button
or the Selector Console to a voice terminal in that group, the Coverage-Group
(COVER-GRP) button on the Attendant Console will not track the call (COVER-GRP
button status LED will not flash). If the call remains unanswered, it will return to the
Attendant Console on the RTN-DA button rather than the COVER-GRP button.
l SLAC only—Whenever the common queue is a receiver for a coverage group and a
call is placed from the attendant position via the START button or the Selector
Console to a voice terminal in that group, an unanswered call will return to the
attendant queue as a Return-On-Don’t-Answer call (instead of as a coverage call).
Send All Calls (DTAC only): If Send All Calls is activated, returning calls will ring at the
DTAC.
Administration Requirements
System:
l Assign number of rings before call return to the Attendant Position (1-31; default =
5).
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							FEATURES AND SERVICES
Attendant Source and Destination (SLAC Only)
Description
This feature allows the attendant, while extending a call, to switch back and forth between
the calling party (the source) and the called party (the destination) before connecting them
together.
Pressing the SOURCE button on the SLAC after the called party has been reached has these
results:
l The called party (the destination) is put on hold.
l The attendant is reconnected to the calling party (the source)
l The green status lamp of the DEST button starts winking to indicate that the
destination is on hold.
l The green status lamp of the SOURCE button goes from winking to dark.
Pressing the DEST button after the source has been reconnected has these results:
l The source is put on hold (again).
l The attendant is reconnected to the destination
l The green status lamp of the SOURCE button starts winking to indicate that the
source is on hold.
l The green status lamp of the DEST button goes from winking to dark.
Considerations
The Source/Destination feature is useful when the attendant needs to talk to each party
privately before connecting them.
Interactions
The Source/Destination feature can only be activated before the two parties are connected
together.
When the attendant presses JOIN, the other parties and the attendant are joined in a 3-way
connection. When the attendant presses RELEASE, the other parties are connected, the call
is separated from the console, and the attendant is free to handle other calls. After the
source and destination parties are connected together, the SOURCE and DEST status lamps
go dark.
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							Attendant Splitting One-Way Automatic
Attendant Splitting One-Way Automatic
Description
This feature allows the attendant to converse privately with a called party while the calling
party is split away on hold.
When the attendant presses START (or a DXS button) to extend an incoming call to a called
party, the calling party is automatically split away from the connection and placed on hold.
This allows the attendant to talk privately with the called party before extending the call. The
attendant can then press RELEASE to complete the transfer or CANCEL to drop the called
station and return to the incoming call.
If the console is a SLAC, the attendant can also use the Join and Source/Destination
features while in the Start mode. Refer to the descriptions of these features for details.
Considerations
Attendant Splitting One-Way Automatic allows the attendant to (1) announce a call, (2)
determine privately whether the called party is available to receive the call, and (3) obtain
information if necessary to redirect the call or take a message.
Interactions
The following features interact with Attendant Splitting One-Way Automatic.
Attendant Source/Destination (SLAC only): This feature can be used after reaching the
called party. It allows the attendant to speak privately to both the calling party and the called
party before connecting them together.
Music-on-Hold: Music-on-hold is not provided to the calling party while the call is split from
the console.
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							FEATURES AND SERVICES
Attendant System Alarm Indication
Description
This feature provides a visible alarm on the Attendant Console to alert the attendant to
problems detected by the system software. The ALARM LED on the Attendant Console will
flash whenever a detected fault persists longer than four minutes, or if more than five
transient faults per hour are detected.The alarm indication should be reported immediately to
your AT&T Systems Technician.
The alarm type that causes an alarm indication is referred to as a Permanent System Alarm.
These alarms are faults that can cause degradation of service and require immediate
attention.
If a flashing ALARM button is pressed, the LED will change from flashing to steadily lit. A
new trouble situation will cause a steady ALARM LED to start flashing again. Only when the
trouble has been corrected will the LED turn off.
Considerations
The ALARM LED on the Attendant Console provides a warning as soon as the fault is
detected. This permits a quick response to system detected faults.
In a two-attendant system, both consoles track problems.
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							Automatic Intercom
Automatic Intercom
Description
This feature allows a multiline voice terminal user including ATL cordless telephone (or
attendant) to place and answer calls to and from another station by use of a dedicated
button appearance.
Automatic Intercom provides a private path between two designated multiline voice terminals.
To place an Automatic Intercom call, the calling party presses the Automatic Intercom (AUTO
ICOM) button and goes off-hook. The calling party hears ringback tone and the called party
receives standard ringing.The status LED associated with the button is steadily lit at the
calling voice terminal and flashing at the called voice terminal. To answer an Automatic
Intercom call, the called party presses AUTO ICOM (not necessary with Ringing Line
Preference) and goes off-hook.
The AUTO ICOM status LED lights steadily whenever the other party is off-hook. This
provides each party with a station-busy indication for the other. To activate the busy-to-idle
reminder, the user can press AUTO ICOM (remaining on-hook). A short burst of tone is
provided when the other party goes on-hook. The user can then go off-hook, and the call
will be placed; the user does not press the AUTO ICOM button again.
Pressing AUTO ICOM to invoke the busy-to-idle reminder overrides Prime Line Preference.
Once activated, the feature can only be canceled by preselection of another button or
answering an incoming call.See the “Busy-to-Idle Reminder” feature description for more
information.
At a Switched Loop Attendant Console, operation of an AUTO ICOM button seizes an idle
loop button for the outgoing call. An incoming Automatic Intercom call arrives on a loop
button and does not flash at the AUTO ICOM button of the console.
Considerations
The intercom feature should not be confused with ordinary station-to-station calling inside
the system using dialed PDCs.With Automatic Intercom, users who frequently call each
other can do so by pressing one button instead of dialing the extension number. In addition,
the station-busy indication and busy-to-idle reminder provide additional utility to users.
This feature is similar to Direct Station Selection (DSS), except that the buttons must always
be assigned in pairs (i.e., between two sets.) Hence, an AUTO ICOM button cannot point to
a single-line telephone.Also, Automatic Intercom calls arrive at the AUTO ICOM button,
thereby providing calling party ID; DSS calls arrive on System Access buttons.
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							FEATURES AND SERVICES
Interactions
The following features interact with Automatic Intercom.
Attendant Position Busy:The inactive attendant is permitted to place Automatic Intercom
calls. Automatic Intercom calls to an inactive DTAC where the AUTO ICOM button is located
in one of the two rightmost button columns will not ring at the console, nor can they be
covered by the active attendant.However, Automatic Intercom calls to an inactive SLAC will
ring there.
Bridging of System Access Buttons:Calls on Automatic Intercom buttons on the principal
station are not accessible from bridged call appearances on the bridging station.
Coverage: Automatic Intercom calls are considered private and do not receive coverage.
Direct Group Calling: Automatic Intercom calls cannot be directed to DGC groups.
Exclusion: Any attempt to engage Exclusion while active on an Automatic Intercom call will
drop the other party.
Last Number Dialed: Numbers called using an AUTO ICOM button are not saved by the Last
Number Dialed feature.
Line Selection (Prime Line Preference): When the Automatic Intercom line is assigned Prime
Line status, the AUTO ICOM button must be pressed to activate the busy-to-idle reminder
even though the I-use LED is already lighted steadily.
Pickup: When an Automatic Intercom call is answered via the Pickup feature, the AUTO
ICOM status LED on the called voice terminal lights steadily. The called party can press
AUTO ICOM to enter the call at any time.
Administration Requirements
Voice Terminal Port:
l Assign AUTO ICOM buttons to voice terminals in pairs. Voice terminals can have
several AUTO ICOM buttons assigned for direct access to multiple stations.
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							Automatic Route Selection (ARS)
Automatic Route Selection (ARS)
Description
This feature provides for the routing of calls over the telecommunications network based on
preferred routes (normally the least expensive route available at the time the call is placed.)
An ARS pattern can be composed of two subpatterns (time of day determines which subpattern is
selected), each consisting of up to three routes, associated Facility Restriction Level (FRL) codes
(described below), and CO overflow flags. A route is identified by specifying a Facility Access Code
for the pooled facility (trunk group); a route may also be identified by specifying a Virtual Facility
code.
A trunk group or virtual facility can be used in more than one ARS pattern and more than once
within a pattern.
Call routing can be specified by as many as eight routing patterns. Each pattern contains a
sequential list of routes (for example, trunk groups) the system can use to complete a call. Number
translations (deletion and addition of dialed digits) necessary to route the call are determined on a
trunk group basis. Overflow to the local CO when all trunks in a pattern are busy or the route FRL is
too high is optional. If all trunks in a pattern are busy (including CO trunks if overflow is allowed),
the call may be queued (via the Callback Queuing feature) on the first route in the pattern.
All calls placed using the ARS access code (default =9) are routed via the feature. The dialed
numbers that follow the ARS access code are generally seven- or ten-digit DDD numbers preceded
by a “1” if required by the serving Central Office. Numbers preceded by a “0” are routed over the
local CO pooled facility.
The present CO numbering plan (expected to be replaced in 1995) is typically a dialed 7-digit
number consisting of a CO code and exchange number in the form NXX-YYYY where N = 2–9, X =
0-9, and Y= 0-9; and a 10-digit number consisting of an area code, CO code, and exchange
number in the form NPA-NXX-YYYY where N = 2–9, P = 0-1, A = 1–9, X = 0-9, and Y = 0-9.
The Interchangeable Numbering Plan Area ([INPA] for 1995 and beyond) allows area codes to be
NAA instead of Area Code. The 10-digit number plan allows CO codes to be XXX.
Each route in a pattern has an associated FRL (0-3). This FRL may differ each time the facility is
specified as a route. A facility with an FRL of “0” is least restricted to callers; an FRL of “3” is the
most restricted. Similarly, each station in the system is assigned an FRL (0-3). A terminal assigned
an FRL of “0” has the least ARS privileges (i.e., routes with FRLs of 1-3 are restricted); an FRL of
“3” provides the most privileges. To use a route, a station’s FRL must be equal to or greater than
the route’s FRL.
The ARS feature, when accessed, selects a pattern as follows:
l Emergency Number Calls (routed via the local CO facility)
l Service Code (N11 or X11, where X= 0 to 9) Calls (routed via an associated routing
pattern)
l International Calls (routed via the administered international pattern)
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							Features and Services
l Calls made to specified COs or seven-digit telephone numbers within the Home Number
Plan Area (Home Area Code). These calls are routed as specified in the Home Area Code
Exception Lists, or else via the Area Code Routing Table, or (by default if not otherwise
specified) the local CO facility.
l Calls made to Area Codes outside the Home Area Code, sometimes referred to as Foreign
Area Codes (FNPAs). The route selected depends on the type of call, as follows:
— FNPA special number calls (includes all “800,” “900,” and Telex 510, 610, 710, and 810
numbers). Each FNPA of the form N00 and N10 may be assigned to a routing pattern.
— FNPA calls made to numbers specified in the FNPA Exception List.
— All other FNPA calls.
ARS Flow Chart
Figure 2-8 provides a simplified ARS flow chart. Bracketed numbers (e.g., [401], [601]) provide a
link between ARS administrable action numbers and the associated item on the flow chart. Certain
readers may find this reference useful when reading the following description in association with the
System 25 Administration Manual. Administrable System, Station, Toll Allowed, and Trunk action
numbers are also noted where applicable.
The ARS feature is accessed when a user dials the ARS access code. As shown on Figure 2-8, the
number dialed is first checked against the Emergency Numbers List. This list consists of special
service code 911 and up to three customer-defined seven-digit numbers. If the number dialed
matches one of the numbers on the list, the call is immediately routed via the local CO facility. All
user call restrictions are disregarded.
If the number dialed is not on this list, a check is made to determine if the terminal is allowed to
originate outside calls. If the terminal is outward restricted, the caller receives Reorder Tone;
otherwise, the dialed number is checked against any toll restrictions that apply.
Terminals may be assigned a Toll Restriction Class (1–5) or be unrestricted (Class 0). Terminals
assigned Toll Restriction Class 1 have the most privileges of restricted terminals; those assigned
Class 5 have the least privileges. There are five associated Toll Call Allowed/Disallowed Lists (1-5)
in the system. Up to 164 3-digit CO codes, 6-digit Area Code plus CO codes, and 6-digit
international codes (consisting of 0 plus 5 international digits) may be divided among the five lists.
Domestic numbers dialed from voice terminals assigned Toll Restriction Class 1 are checked
against all five Toll Call Allowed (TCA) Lists; domestic numbers dialed from Class 2 terminals are
checked against TCA Lists 2–5; domestic numbers dialed from Class 3 terminals are checked
against TCA Lists 3–5; domestic numbers dialed from Class 4 terminals are checked against Lists 4
and 5; and numbers dialed from Class 5 terminals are checked against List 4 only. If a domestic
number dialed does not appear or if an international number does appear in a checked list, the user
receives Reorder Tone. Calls originated at unrestricted (Class 0) terminals are not checked.
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							Automatic Route Selection (ARS)
Calls are checked to determine if they are international calls or operator calls. Dialed numbers “01”
or 011 signify international calls, “0” plus a number other than “1” signify operator calls (00 calls
signify Intra-Lata operator calls). If the call is an international call and the terminal is not restricted,
the international routing pattern is selected and the call routed accordingly. Operator calls are
routed via the local CO facility.
Calls within the Home Area Code are checked to determine if a special W11 service code (N = 0-8)
has been dialed. Dialed W11 codes assigned a routing pattern are routed via the routing pattern. All
other call types are checked against the Home Area Code Exception Lists. There may be up to four
of these lists, each with an associated ARS Routing Pattern. Up to 800 3-digit office codes may be
divided among the four lists (eight entries may be 7-digit numbers). If a match is found, the call is
routed via the associated ARS Routing Pattern. If no match is found, the dialed number is routed
via the Home Area Code pattern (specified in the Area Code Routing Table), or if none is specified,
via the local CO facility.
If a number is entered more than once in the exception list, the pattern used will be the pattern
associated with the more specific number.
The Area Code Routing Table is simply a listing of North American Plan Area Codes and Special
Number Area Codes, each having an associated ARS Routing Pattern (all pre-1995 North
American Area Codes are assigned routing pattern 1 by default). A dialed Area Code that is listed in
the table is routed using the associated pattern. Calls to Area Codes not listed are routed via the
local CO facility.
The dialed non-local numbers without a route assigned are checked against the Other Area Code
Exception List. Up to 512 entries maybe assigned to the list. Each entry must consist of a 3-digit
NPA code, 3-digit CO code, and two additional digits (for a total of 8 digits). The last four digits may
be “.”,which matches any digit. Each entry has an associated ARS Routing Pattern. If a match is
found, the call is routed using this pattern. If no match is found, the call is checked against the NPA
Routing Table. A dialed NPA that is listed in the table is routed by using the associated pattern.
Numbers that dont match are routed via the local CO facility.
ARS Routing Pattern Table
Figure 2-9 provides a block diagram of an ARS Routing Pattern. Up to eight of these patterns may
be administered in the system. Each pattern consists of two subpatterns that maybe chosen based
on the time of day. Each subpattern (A and B) can contain up to three allowed routes. If all routes in
a subpattern are busy, a CO overflow flag (when set) allows the call to be routed via the local CO
facility; otherwise, the call will queue on the first route in the subpattern.
Administrable Start and Stop times (Hour and Minute) for Routing Subpattern A specify when
Subpattern A should be used to route calls. Subpattern B is used to route calls at all other times.
Each route is specified by its trunk group facility access code or Virtual Facility code and an
associated FRL.
November 19952-59