AOH :: P46-25.TXT

AT&T Definity System 75/85

                              ==Phrack Magazine==

                 Volume Five, Issue Forty-Six, File 25 of 28


                          AT&T Definity System 75/85
                             Communications System
                          Description & Configuration
                              Written By: erudite

Let me introduce you to the AT&T Definity System 75/85.  This communications
system is a product of the merging of the AT&T System 75 and System 85
architectures.  The name Definity came from the two words "definitive" and

Let me also tell you that there are many different communications systems
out there. (Merlins, AT&Ts) Many many many, I couldn't name them all, but
the AT&T systems are nice.  I enjoy working with them, and I hope you enjoy
this text file.

This System is an advanced business communications system.  A Digital
Communications Protocol (DCP) allows data communication through data
terminal equipment connected to the digital switch.  This allows the
system to handle data and voice communications simultaneously.

The System can handle up to 1600 lines that supports all digital, hybrid,
and analog terminals and equipment.  Up to 400 trunks, and up to 400
Automatic Call Distribution (ACD) Agents.  The Data switching capacity is up
to 800 digital data endpoints, and 160 integrated and combined pooled modem

  ~ 510D Personal Terminal or 515-Type Business Communications Terminal
  ~ 7404D Terminals
  ~ 7406D or 7407D Equipped with optional Data Module Base
  ~ Asynchronous Data Units (ADU) (DCE type device that has rs232c interface)
  ~ Digital Terminal Data Modules
  ~ 3270 Data Modules
  ~ Internal Data Channels
  ~ Trunk Data Modules (Modular)
  ~ Processor Data Modules (Modular)


The Processor Port Network (PPN) always provides the switch processing
element (SPE) and port circuits.  An Expansion Port Network (EPN) is
available to increase line size of any system by allowing you to add
additional port circuits.  The EPN connects to the PPN over a fiber
optic cable that may be up to 1.86 miles remotely situated.  It may also
by located adjacent to the PPN.

This System may be arranged stand-alone or you can integrate it into a
private network.  You can form these types of Networks:
        ~ Tandem Tie Trunk Network (TTTN)
        ~ Electronic Tandem Network (ETN)
        ~ Main/Satellite Configuration
        ~ Distributed Communications System (DCS)
        ~ Centralized Attendant Service (CAS)

An Integrated Services Digital Network Primary Rate Interface (ISDN-PRI)
makes it possible for the Definity System to access various private and
public network services.  With ISDN-PRI the you can access these services:
        ~ Call by Call Service Selection
        ~ Private Network Services
        ~ Information Forwarding
        ~ Call Identification Display
          - Connected Number Display
          - Connected Party Name Display
          - Calling and Called Number Record Display
          - Calling and Called Party Name Display


The Actual System is encased in a pair of "cabinets" which have a fiber
optic link between them.  It is also common to have a stack of about three
"cabinets" of a smaller size, for different models.

Shown here is a typical multi-carrier system with a Processor Port Network
(PPN) cabinet and Expansion Port Network (EPN) cabinet.

  attendant          outside trunks   _____ outside private line
   consoles            and lines    /        data transmission equipment or
      \                      \    /          analog switched network
        \      fiber optic    |  |
         |      connection    |  |         __ business communication
        -+---------/~\--------+--+       /    terminals
       |   AT&T    | |   AT&T    |      |
       | DEFINITY  | | DEFINITY  +------'                      ___data
    ---+  SYSTEM   | |  SYSTEM   +--------<>------[audix]    /    terminals
  /    |  75/85    | |  75/85    |   modular data          /
 |     |___________| |__________+|     processor     ____ |
manager   |   |                 |                   |    +'optional host
terminal  |   |                 +-------<>----------+    | computer or call
         /    +-------[]-----+,                     |____| management system
       /         asynchronous |
  single line     data unit    \__ data
voice terminals                    terminals

  Voice and Data
Management Features

There are a lot of voice features and services, in fact, too many to list, I
will do a run down on all the interesting and useful features and services.
It has many Voice Management, Data Management, Network Services, System
Management, Hospitality Services, and Call Management Services.

  call attendant can use to operate the console more efficiently
  both inside system users and remote callers to edit, receive, send,
  write, and forward voice messages.
  it to the display console.
  - Attendant Conference: Allows Attendant to construct a conference call
  - Terminal Conference: Allows remote user to construct a conference call
    without attendant assistance.
  being interrupted by any of the systems overriding features, and denies
  ability to gain access to, and or superimpose tones.
  is issued by the administrator to a certain extension # for indication of
  a dedicated private data extension.
  the system to dial anyone else, such as the attendant console.
  the following trunks and more.
        ~ Voice Grade DS1 Tie Trunks
        ~ Alternative Voice/Data (AVD) DS1 Tie Trunks
        ~ Digital Multiplexed Interface (DMI) Tie Trunks
        ~ Central Office (CO) Trunks
        ~ ISDN-PRI Trunks
        ~ Remote Access Trunks
        ~ Wide Area Telecommunications Service (WATS) Trunks
  features and functions that is used for maintenance testing.  Such as access
  to system tones, access to specific trunks, etc.
        Note: AT&T designed the Facility Test Calls Feature for testing
              purposes only, and system maintenance.  When properly
              administered, AT&T claims that the customer is responsible for
              all security items, and secure system from unauthorized users,
              and that all users should be aware of handling access codes.
              AT&T claims they will take no responsibility for poor
  it rings down if busy, or if it receives a dial timeout.
  packet switched local area network that will link with mainframes,
  workstations, personal computers, printers, terminals, storage devices,
  and communication devices.
  This interface allows connection of the system to an ISDN Network by means
  of ISDN frame format called PRI.
  branch has a Listed Directory Number (LDN).
        ~ Common Control Switching Arrangement (CCSA)
        ~ Electronic Tandem Network (ETN)
        ~ Enhanced Private Switched Communications Service (EPSCS)
        ~ Tandem Tie Trunk Network (TTTN)
        ~ Software Defined Network (SDN)
  doesn't want to take responsibility for anything that is abused with this
  would come in handy.
  others calls, again, AT&T does not want to take any legal fees on misuse
  on this feature.
  attendant's assistance.


The System comes with switched services software, administrative software,
and maintenance software.  All running on a real-time operating system.

  and services.  This also is responsible for relaying any information to the
  console display.
  tasks, and configurations.
  keep everything running properly.

System Administration

The "Access Code" you will encounter on these systems is a 1, 2, or 3 digit
number. The pound (#) and star (*) keys can be used as the first digit of the
code.  Below you will see a typical Screen Format taken from one of my logs,
information aside you can see and get a feel of what the administration side of
the system is like.                                                                            Page 1 of 4


Extension: ____
Type: _____       Lock Messages: _      COR: _     Room: _____
Port: ___________ Security Code: ____   COS: _     Jack: _____
Name: ___________ Coverage Path: ___              Cable: _____


    LWC Reception? _____  Headset? _  Coverage Msg Retrieval? _
   LWC Activation? _  Auto Answer? _        Data Restriction? _
 Redirect Notification? _        Idle Appearance Preferences? _
PCOL/TEG Call Alerting? _
           Data Module? _           Restrict Last Appearance? _
               Display? _


        List1: _____        List2: _____        List3: _____


1: _______                     6: _______
2: _______                     7: _______
3: _______                     8: _______
4: _______                     9: _______
5: _______

System Maintenance

Finally the Maintenance section, where you can see where the errors are
logged, where all the alarms are sent, printed, etc.

There are 3 different types of alarms:
  console or INADS)

The Error log is reported and can be viewed at The Manager Terminal,
as well as the alarm log.

Basic Acronyms

ADU     Asynchronous Data Unit
AUDIX   Audio Information Exchange
COR     Class of Restriction
COS     Class of Service
DCP     Digital Communications Protocol
DMI     Digital Multiplexed Interface
EPN     Expansion Port Network
ISDN    Integrated Service Digital Network
PPN     Processor Post Network
PSDN    Packet Switching Data Network


Here is most of the Tones, mostly either interesting ones or often used
tones the System.  Here are the tones, the frequencies, and the moderations.

Tone                   Frequency          Pattern
----                   ---------          -------
Answer Back 3          2225 Hz            3000 on
Answer Back 5          2225 Hz            5000 on
Bridging Warning       440 Hz             1750 on, 12000 off,
                                          650 on; repeated
Busy                   480 Hz + 620 Hz    500 on, 500 off; repeated
Call Waiting
 Internal              440 Hz             200 on
 External              440 Hz             200 on, 200 off
 Attendant             440 Hz             200 on, 200 off
Priority Call          440 Hz             200 on, 200 off, 200 on,
                                          200 off, 200 on
Call Waiting
 Ring Back             440 Hz + 480 Hz;   900 on (440 + 480)
                       440 Hz             200 on (440) 2900 off; repeated
Cnrt Att Call
 Incoming Call
 Identification       480 Hz & 440 Hz    100 on (480), 100 on (440),
                       & 480 Hz           100 on silence;
 Dial Zero,
 Attendant Transfer,
 Test Calls,           440 Hz             100 on, 100 off, 100 on
 Coverage              440 Hz             600 on
 Confirmation          350 Hz + 400 Hz    100 on, 100 off, 100 on,
                                          100 off, 100 on
 Dial                  250 Hz + 400 Hz    Continuous
 Executive Override    440 Hz             300 on followed by
 Intercept             440 Hz & 620 Hz    250 on (440),
                                          250 on (620); repeated
 Ringback              440 Hz + 480 Hz    1000 on, 3000 off; repeated
 Zip                   480                500 on


  System 75/85 (multi-carrier cabinet model) communications system.

I hope you learned something, anywayz, questions comments, system login
information, defaults, where to get manuals, or anything else:
email me ( and I will get back to you.

Version: 2.3a


erudite ( (armitage on irc)

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