ATT System 25 Reference Manual

							OVERVIEW
SYSTEM
CALL ACCOUNTINGCONTROL
SOFTWARE ORRS232COMPLEX
SMDR PRINTER
SYSTEM ADMINISTRATION
TERMINAL OR
RS232
MS-DOS PC WITH
ADVANCEDADMINISTRATION
DIGITAL TAPE UNIT ORRS232
MS-DOS PC WITH
ADVANCEDADMINISTRATION
TRUNK FACILITIES
l DID
l FX
l TIE
l WATS
l COPAGING
l AUXILIARY-DICTATIONEQUIP
SINGLE-LINEANALOG
VOICE TERMINAL
MULTILINE VOICE
TERMINAL AND ATL
CORDED AND CORDLESS
TELEPHONES
DIRECT TRUNK
ATTENDANT CONSOLE ORHYBRID
SWITCHED LOOP
ATTENDANT CONSOLE
l MUSIC SOURCE
l EXTERNAL ALERTANALOGl RECORDED
ANNOUNCEMENT
l DICTATION
EQUIPMENT
RIMSACCESSANALOG
HYBRID
ANALOG
TRUNK
SWITCHINGNETWORK
RS232
ANALOG
STATIONINTEGRATED SOLUTION
l ADVANCED ADMINISTRATION
l CALL ACCOUNTING SOFTWARE
l OFFICE AUTOMATION SOFTWARE
l VOICE MESSAGE SYSTEM WITH
– AUTOMATED ATTENDANT SERVICE
– CALL COVERAGE SERVICE
– VOICE MAIL SERVICE
– ANNOUNCEMENT SERVICE
– MESSAGE DROP SERVICE
DATA
ASYNCHRONOUS
DATA UNITHOST COMPUTERSTERMINALS
PRINTERS
ANALOGMODEMS
MODEM
DIGITAL DEVICES
STARLAN NETWORK
WORKSTATIONS
STARLAN NETWORK
GATEWAY
STARLAN NETWORK
PRINT AND
FILE SERVERS
STARLAN NETWORK
HOSTS
HYBRIDMS-DOS PCWITH CALLMANAGEMENT
DIGITALTRUNK
DIGITAL TRUNK
FACILITES
l DID
l FX
l TIE
l WATS
l CO
l OFF-PREMISES
EXTENSION
Figure 1-1.System 25 Block Diagram
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							OVERVIEW
be used to set up connections between data terminals, word processors, personal
computers, and host computers.System 25 uses intelligent port circuits equipped with
distributed network processor elements to provide (essentially) nonblocking voice and data
switching.
Voice communications features combine traditional telephone features, such as Transfer and
Hold, with advanced features, such as Individual and Group Coverage, Hands-Free Answer
On Intercom, and Speed Dialing (see Section 2, “Features and Services”).
Data communications features provide switched data connections supporting transmission of
voice and data over Premises Distribution System wiring.Data connections can be made
between two digital data modules (asynchronous data units), between two analog modems,
or between an analog modem and a digital data module. System 25 also provides access to
STARLAN NETWORKS (Release 2 of STARLAN only). The system has data modules that
provide a RS-232 interface for full duplex, asynchronous, transmission of data up to 19,200
bps, and an integrated 212A-compatible modem pool resource.
System 25’s Integrated Solution offers customers a unique package of integrated call
management,switch management,and office automation applications. The Integrated
Solution is a set of application programs that run on a Master Controller (UNIX® PC). The
applications include Advanced Administration Software (AAS), which permits customers to
administer System 25’s features themselves;Call Accounting System (CAS); and an
integrated Voice Message System (VMS) that provides call coverage, leave word calling,
automated attendant, and voice mail services.In addition, a number of generic office
automation applications (word processing, data base management, and spreadsheet) are
also available for the Integrated Solution; these applications may be run simultaneously with
the VMS and CAS applications.
System 25 supports the following:
l Trunk and Network Facilities—Dual Tone Multifrequency (DTMF) and Dial Pulse
Signaling on incoming and outgoing trunks (dial pulse only on DID trunks).
— Loop Start (LS)
— Ground Start (GS) (Strongly Preferred over Loop Start in most installations)
— Tie Trunks (Type I and Type I Compatible E&M, Type V Simplex)
— Direct Inward Dialing (DID)
l Voice Terminals —
Single-Line Touch-Tone, Single-Line Rotary, MET, 7300H Series
Multiline, and ATL Corded and Cordless telephone sets.
l Data Facilities
— Digital Data End Points— RS-232 Interfaces via Asynchronous Data Units
— Analog Data End Points— Tip/Ring-Type Modem Interfaces
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							OVERVIEW
— STARLAN NETWORK Access (Release 2 of STARLAN only)
— DS1 Facility interface.
l Networking Capability
— Remote Access
— Tie Trunks
— Tandem Trunking
— Endpoint in Electronic Tandem Network (Tributary only, not Satellite)
— Endpoint of Enhanced Private Switched Communications Services (EPSCS)
— Endpoint of Tandem Tie Trunk Network (TTTN)
— Endpoint of Common Control Switching Arrangement (CCSA)
— DS1 Facility Interface.
Call Handling Capabilities
System 25 can be arranged as a stand-alone system or can be part of a private network.
The system provides 256 ports to support the following:
l 115 simultaneous two-party conversations
l Traffic Handling Capacity of 4140 CCS (Trunking Limited)
l Busy Hour Call Capacity of 2500 calls (DTMF Register Limited)
l Up to 104 trunk ports including Central Office (CO), DID, Tie, Foreign Exchange (FX),
Wide Area Telecommunications Service (WATS), and 800 Service
l An Auxiliary Trunk interface for paging and dictation systems
l Up to 240 ports that support a combination of the following:
— Up to 200 ports for voice terminals and auxiliary feature port equipment.
— Up to 104 data ports providing RS-232 connections to data terminals,
personal or multiport computers.
Refer to Hardware and Software Parameters as provided in “Technical Specifications”
(Section 5) for detailed specifications.
Safety
System 25 meets all requirements found in Underwriters Laboratories Standard for
Telephone Equipment (1459).
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							OVERVIEW
Business Communications Needs
The remainder of this section describes how System 25’s features may be used to satisfy a
customer’s communications needs. This material may be thought of as the reverse of the
“Features and Services” in Section 2.
The business communications capabilities of the majority of small businesses with more than
30 phones are provided by a PBX. System 25 is a PBX designed to meet the business
communications needs of customers in the 30 to 150 station range.
The communications needs of most business customers falls into five basic categories.
Customer experience has shown that a PBX needs to provide—
l Prompt handling of incoming calls to maximize revenue opportunities and client
satisfaction,
l Ease of access to and cost control of outgoing calls over public network and private
facilities,
l Easy movement of calls between on-premises phones and between on-premises and
off-premises phones,
l Sharing of data between PCs and/or host computers and data terminals, and
l Growth and rearrangement of facilities.
The following pages outline System 25’s outstanding ability to provide these services.
Incoming Business Communications
Successful call termination is the key to capturing all incoming communications associated
with revenue issues, client inquiries, decision data, etc. Call termination involves identifying
the called party and routing the call to a primary or secondary answering position. System
25 provides powerful tools for both call screening and call termination.
l Attendant Consoles allow one or two attendants to answer, screen, and steer
incoming calls using either Direct Trunk or Switched Loop operation. With attendant
operation, incoming calls can be screened and extended to the appropriate party for
resolution or forwarded to alternate locations, and messages can be taken for absent
clients. Calls may arrive over any of the network facilities described in later sections
of these notes.
l System 25’s Integrated Solution can provide Automated Attendant service, either
reducing the volume of calls your attendant needs to handle or providing off-hour
attendant service.
l Direct Inward Dialing allows incoming callers to reach specific individuals or facilities
without attendant assistance.This allows specific numbers to be advertised for
direct customer access to brokers, emergency services, etc., over a shared pool of
DID trunks.
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							`OVERVIEW
l The Call Management System provides Automatic Call Distribution (ACD) service and
associated call traffic and agent performance reports.
l Direct Group Calling (DGC) allows incoming calls to be directed to a specific group of
stations. Calls to a DGC group hunt for an idle station in a circular manner, starting
at the station following the last one called.If all group members are busy, calls are
queued and can be sent to a delay announcement.A DGC group can terminate calls
to sales, services, computer, announcement, etc.,over either ordinary CO trunks or
DID trunks.
l Personal Lines provide dedicated outside lines for multiline voice terminal users and
are accessed via a dedicated button for both incoming and outgoing service. Up to
16 terminals may share a Personal Line with up to 4 parties simultaneously off-hook.
A personal line provides direct access to brokers, emergency service, etc., over a
dedicated loop start or ground start trunk.
l Call Waiting lets users know that they have another incoming call and helps avoid
missing important calls.
l Remote Access allows employees to use the services and facilities of System 25
from home or when they are on the road.Barrier codes prevent unauthorized
access.
Frequently, the called party is not available to handle an incoming call. System 25 provides a
number of methods for redirecting incoming calls to alternate resources.
l Coverage allows calls that are not answered within a specified number of rings to be
redirected to an individual covering station and/or a group of covering stations. This
is especially useful for Boss-Secretary arrangements, staff backup, and message
service.This feature is versatile enough to permit suitable alternate answering
arrangements for virtually every level of employee. Special features, such as the
Send All Calls feature which routes a user’s calls directly to covering station(s),
accommodate the day-to-day variations that occur in an employee’s work schedule.
l Following and Forwarding allow users who are away from their normal locations to
receive their calls at other phones inside the system or (Forwarding only) outside the
system.This feature supports roving personnel and shared office space for
company staff.
l The Integrated Solution can provide call coverage service, along with integrated voice
mail and Leave Word Calling.
l The Bridging feature permits calls on a user’s System Access buttons to be
answered at another station on Bridged Access buttons.
l The cordless telephone set allow users who are away from their normal locations to
receive their calls at other locations within 1000 feet (maximum based on
environmental conditions) of the base unit. This telephone supports personnel who
are frequently away from their desks.
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							OVERVIEW
l Station Hunting provides automatic redirection of incoming calls to an idle member of
a hunt group when the called party is busy.
l Pickup allows a user to answer a call ringing at another terminal. Directed Pickup
allows a user to answer a call ringing at any terminal by dialing the pickup code and
the Personal Dial Code (PDC) of the ringing station. Group Pickup permits calls to
any other terminal in the pickup group to be answered by dialing the group call
pickup code. With Pickup, users do not have to leave their phone to answer other’s
calls.This feature is especially useful for local coverage in group offices not
supported by secretarial service and equipped with economical single-line phones.
When alternate resources are not available to handle an incoming call, System 25 provides
for attendant handling of the call utilizing camp-on, redirection, and/or message service.
l Camp-On allows the attendant to extend an outside call to a busy station. A burst of
tone is heard at the called station to notify the user of the camped-on call. The caller
is placed on hold and hears music-on-hold, if available. When the user hangs up, the
camped-on call begins ringing immediately. The Return Coverage on Busy feature
returns unanswered camped-on calls to the attendant for service after a specified
interval.
l Return Coverage on Don’t Answer returns unanswered attendant-extended calls for
additional service (redirection/messaging).
l Messaging Service supports activation of a light-emitting diode (LED) at the called
station to indicate that the attendant, message desk, or another station has a
message for the user.
Special arrangements are needed to handle incoming calls during periods when the normal
staff is not available, for example, at night and on weekends. System 25’s Night Service
feature allows on-duty personnel to answer incoming attendant-seeking calls when the
attendant is not on duty. Directed Night Service redirects incoming attendant-seeking calls to
designated voice terminals, such as a guard desk or coverage position. Trunk-Answer-
From-Any-Station (TAAS) Night Service allows users to answer incoming calls from any
station by dialing the Night Service access code.Night personnel can be alerted by a night
bell.
Outgoing Business Communications
One of the key functions of a customer premises communications system is to provide easy
access to the most cost effective network facilities for outgoing calls. The system needs to
be capable of steering calls based on cost, and must also keep records of incoming and
outgoing calls and associated costs.Building on its ground start trunk capability, System 25
features control costs and record usage as follows.
l Call Restrictions allow the manager to restrict users from making certain types of
calls. Restriction is administered through outward restriction, toll call restriction, and
facility access restriction.
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							OVERVIEW
l Automatic Route Selection provides manager defined routing of calls over the
telecommunications network based on preferred routes (normally the least expensive
route available at the time the call is placed) with capacity for multiple common
carriers and routing through tandem switch points.The user dials a standard Direct
Distance Dialing (DDD) number and the system selects the call route.
l Station Message Detail Recording (SMDR) generates detailed call information on all
incoming and outgoing calls and sends this information to an output device (PC or
printer).
l Call Accounting Systems provide multiple types of customer reports on
communication costs and usage.
l Account Code Entry allows a user to associate calls with an account code for
charge-back purposes.This feature can be administrated (on a per-station basis) to
force the entry of the required codes before outgoing calls can be made.
Ease of access to multiple types of network facilities (provided for minimum cost) is managed
by the following features.
l Automatic Route Selection (ARS) allows the customer to dial a standard DDD
number. ARS selects the preferred route and does any number conversions required
for the facilities selected.
l System 25’s Virtual Facility feature provides convenient and inexpensive access to
Other Common Carriers (OCCs). This feature provides access to OCC facilities over
a user specified physical facility; dedicated OCC trunks are not needed. Local OCC
access numbers and account codes are automatically added by System 25. System
25’s Virtual Facility feature is fully integrated with its ARS, Toll Restriction, and
SMDR/CAS features.
l Callback Queuing provides a simple way to complete calls to busy trunk pools
without having to manually repeat the calling procedures. Such calls are put into a
queue; when the busy facility is available, the originator is alerted and the call is
completed.
l Last Number Dialed automatically saves the last number dialed and allows the user
to retry the number without redialing (multiline voice terminals only).
l Callback Queuing puts a call made to a busy facility into a queue, notifies the calling
user when the facility becomes available to receive the call, and completes the call.
l Repertory Dialing allows multiline voice terminal users to store a telephone number
or account and associate that number with a button on their voice terminal. Pressing
a Repertory Dialing button is equivalent to dialing the stored number (one-touch
dialing).
l System Speed Dialing allows all users to dial 90 selected numbers using 3-digit
codes. Users can also program up to 20 Personal Speed Dialing Numbers, which
are accessible only from their terminals.System Speed Dialing can be used by the
system administrator to hide business account codes from users.
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							OVERVIEW
l Pooled Facility-Dial/Direct Access allows both multiline and single-line voice terminal
users to access a common pool of trunks for outgoing calls by dialing a facility
access code, or, on multiline voice terminals, by pressing a button. This grouping
provides resource pooling, which results in better service with a given number of
trunks.
l Personal Lines provide dedicated outside lines for multiline voice terminal users.
Personal lines are accessed via a dedicated feature button. Up to 16 terminals may
share a personal line.
l Third-Party Call Setup allows PCs to set up calls between a System 25 voice/data
terminal and any other facility. A PC application program could use this capability to
retrieve information from a data base.
Last Number Dialed, Repertory Dialing, and Speed Dialing are also applicable to dialing and
managing internal calls. Personal lines provide both incoming and outgoing service.
Internal Call Movement
Typically, about 40 percent of PBX calls are internal calls, call transfers to another location,
conference of multiple locations, temporarily suspended calls, page to locate the called party,
etc. Rapid placement of internal calls and easy call movement from the answering station to
a new station are supported with numerous features in System 25.
To provide easy internal call setup, System 25 provides the following features.
l Direct Station Selection (DSS) allows one-button access from a multiline voice
terminal to another voice terminal, a pooled facility, paging zone, or DGC group. The
DSS status LED reflects the idle/busy status of the associated termination point.
This feature is used to track and contact frequently called associates.
l Automatic Intercom allows multiline voice terminal users to call each other by use of
a dedicated line appearance. A private dedicated path ensures that a path is always
available. This feature is frequently used in Boss/Secretary arrangements.
l The Dial Plan for System 25 is based on the concept that, whenever possible, calls
should be placed to individuals rather than to pieces of equipment. To implement
this concept, individuals are assigned PDCs and are allowed to sign in those PDCs at
other terminals. The system automatically routes the call to the home terminal or
signed-into terminal. This significantly increases the probability of reaching the called
party. In addition, the Dial Plan is built on a flexible numbering scheme that allows
the number of dialed digits to match assigned PDCs (2/3/4 digit dial plans) and to be
administered to match telephone company assigned Direct Inward Dialing numbers.
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							OVERVIEW
Efficient internal call termination is supported with the following features.
l Distinctive Ringing provides various patterns of ringing to allow users to distinguish
outside calls, inside calls, callbacks on queued calls, and calls set up at an
associated data terminal.
l Hands-Free Answer on Intercom (HFAI) allows Speakerphone and HFAI terminals to
auto-answer inside or attendant extended calls. With HFAI active, the set generates
a tone burst over its speaker to alert the calling and called party of the call
completion.Both parties may then converse;no action by the called party is
required.
Frequently, the first termination point for a call is not its final destination. To support internal
call movement, System 25 provides the following features.
l Bridging of System Access and Personal Lines allows calls to be passed in a manner
that key system users are familiar with.
l Transfer allows a user to transfer any call to another voice terminal. This feature
supports transfer of calls from the answering position to another location for
completion of a transaction.Examples are secretary to boss, office to lab, broker to
specialist, etc.
l Conference allows up to five parties (maximum two outside), including the originator,
to participate in a call. This feature supports add-on of additional parties to a call for
joint consultation, crisis management, schedule coordination, etc.
l Hold allows a user to suspend a call. The Hold feature allows users to temporarily
disconnect from one conversation and either place or answer another call. Music or
information bulletins may be provided to the held party. Called parties frequently use
the hold period to access computer data bases, search categories, and/or consult
with others via a second phone call.
l Following and Forwarding provide users with ways to answer their incoming calls
while temporarily away from their home terminals.
l Park allows a user to place a call or conference on hold and then pick up the call
from any voice terminal.The user can page another party to pick up the parked call
or may move to another location and then re-access the call.
Data Communications
Small Business customers have started to integrate PCs into their day-to-day business
operations.Businesses have found a need to access the data bases (sales, inventory,
personnel) in these PCs from more than one location (both on- and off-premises). System 25
data features are specially engineered to enhance a user’s ability to access data from
multiple locations.
System 25 has been designed to help these businesses use their
personal computers, data terminals, and host computers more effectively by providing the
following features.
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							OVERVIEW
l Circuit switched data communications up to 19,200 bps (RS-232 interface) provide
circuit switched connections from asynchronous data terminals, PCs, or host
computers to host computers or network facilities. Users can be located and/or
moved to any on-premises office equipped with the standard AT&T 4-pair wiring plan.
Thus an asynchronous terminal or PC can have access to multiple host computers,
remote data bases via a modem pool, and a local area network (STARLAN) via
System 25’s STARLAN NETWORK gateway.
l Packet switched data connections at 1 million bps over AT&T’s STARLAN NETWORK
local area network provide data transfer between client PCs and servers (PCs/host
computers/printers, etc.) on the local area network (LAN). LAN users can be located
and/or moved to any on-premises office equipped with standard AT&T 4-pair wiring.
The LAN allows PCs to share facilities (printers, disk systems, modem pools, etc.).
l System 25’s STARLAN NETWORK ACCESS software and STARLAN NETWORK
gateway provide access to the STARLAN NETWORK for off-premises and occasional
on-premises users.These users do not need to install a Network Access Unit (NAU)
in their PCs to use the STARLAN NETWORK ACCESS software. The data transfer
rate is limited to 9600 bps or, for off-premises users, by the modem.
Note:System 25 is compatible only with Release 2 of the STARLAN
NETWORK.
LAN users can access hosts connected to System 25, or, if their System 25 is
equipped with a modem pool, remote hosts.Finally, terminals and PCs connected to
System 25 data ports can access host computers on the LAN.
Frequently a user needs to access a LAN data base at or from a remote location (home,
motel, client office, branch, etc.). To support out-of-building access to computer data over
network facilities or Off-Premise Station (OPS) lines, System 25 provides the following
features.
l Modem pooling allows data terminals to communicate over analog facilities utilizing
the standard dialing plan and provides full access to all network facilities, cost control
mechanisms, ARS, and incoming call management tools (DID/attendant/DGC, etc.).
l Transfer to data allows a data call to be set up on a voice terminal and then to be
transferred to a data terminal or computer. This feature can also be used to enter an
account code for the data call.
l The System 25 STARLAN NETWORK gateway allows the LAN environment to be
extended to occasional users or remote locations. Off-premises users can access
the LAN utilizing all the network features, cost control mechanisms, and incoming call
management facilities of System 25.The data transfer rate is governed by the
modem.
Setting up data communications with PCs, host computers, and/or remote access can be a
source of confusion for occasional users. The following special data features are provided
by System 25 to assist the user in utilizing its rich set of data communications capabilities.
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