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Telecommunications glossary

adaptive differential pulse code modulation

A means of encoding analog voice signals into digital signals by adaptively predicting future encoded voice signals. This adaptive modulation method reduces the number of bits required to encode voice.


The process of setting up a system (such as a switch or a messaging system) to function as desired. Options and defaults are normally set up (translated) by the system administrator or service personnel.


Consisting of alphabetic and numeric symbols or punctuation marks.

American Standard Code for Information Interchange

A standard code for data representation that represents alphanumeric characters as binary numbers. The code includes 128 uppercase and lowercase letters, numerals, and special characters. Each alphanumeric and special character has an ASCII code (binary) equivalent that is 1 byte long.


An analog signal, such as voice or music, that varies in a continuous manner. An analog signal may be contrasted with a digital signal, which represents only discrete states.

asynchronous communication

A method of data transmission in which bits or characters are sent at irregular intervals and spaced by start and stop bits rather than by time.

asynchronous data unit

An electronic communications device that allows computer systems to communicate over asynchronous lines more than 50 feet (15 meters) in length.

asynchronous event

An event detected by the system that disrupts the normal flow of an application that is running. At present, the system recognizes only one type of asynchronous event in TAS applications--a hang up. In VoiceXML, the system also recognizes an error event.

asynchronous transmission

A form of serial communications where each transmitted character is bracketed with a start bit and one or two stop bits. The alarm card provides asynchronous EIA-232 capabilities.

automatic call distributor

That part of a telephone system that recognizes and answers incoming calls and completes these calls based on a set of instructions contained in a database. The ACD can send the call to an operator or group of operators as soon as the operator has completed a previous call or after the system has played a message to the caller.

automatic number identification

A method of identifying the calling party by automatically receiving a string of digits that identifies the calling station of a particular customer.

back up

The preservation of the information in a file in a different location so that the data is not lost in the event of hardware or system failure.


A duplicate of a file or group of files from a system that is (typically) not stored on the system. The purpose of a backup is to be able to replace (or restore) the original files if the originals are damaged or destroyed.

basic input/output system (BIOS)

Program instructions that provide low-level control of peripheral devices, including status and error handling. Peripheral devices include keyboards, video, disks, printers and serial ports.

batch file

A file containing one or more lines, each of which is a command executable by the UNIX shell.


A unit of measurement that describes the speed of transferred information.

baud rate

Transmission signaling speed.

bearer channel

A digital channel with basic services that typically allows transmission rates of 64 kilobits per second in both directions.

binary digit

Two-number notation that uses the digits 0 and 1. Low-order bits are on the right (for example, 0001=1, 0010=2, and so forth). Four bits make a nybble; eight bits make a byte.

binary synchronous communications

A character-oriented synchronous link protocol.


See binary digit.

bits per second

The number of binary units of information (1s or 0s) that can be transmitted per second. Mbps refers to a million bits per second; Kbps refers to a thousand bits per second.

blind transfer protocol

A protocol in which a call is completed as soon as the extension is dialed, without having to wait to see if the telephone is busy or if the caller answered.


The operation to start a computer system by loading programs from disk to main memory (part of system initialization). Booting is typically accomplished by physically turning on or restarting the system. Also called reboot.

boot code

On-board firmware installed by the factory that is used to load the core firmware. Runs only on the alarm card processor as it initializes.


See bits per second.


A temporary storage area used to equalize or balance different operating speeds. A buffer can be used between a slow input device, such as a terminal keyboard, and the main computer, which operates at a very high speed.

built-in self-test

Alarm card-specific hardware diagnostic software. It checks the viability of the alarm card's components each time the board starts up.


A unit of storage in the computer. On many systems, a byte is 8 bits (binary digits), which is the equivalent of one character of text.

call classification analysis

A process that enables application designers to use information available within the system to classify the disposition of originated and transferred calls.

call progress tones

Standard telephony sounds that indicate the status of the call. These sounds include busy, fast busy, ringback, reorder, etc.

called party number

The number dialed by the person making a telephone call. Telephone switching equipment can use this number to selectively route an incoming call to a particular department or agent.

card cage

An area within a hardware platform that contains and secures all of the standard and optional circuit cards used in the system.


An admonishment or advisory statement used in the system documentation to alert the user to the possibility of a service interruption or a loss of data.

central office

A location in which large telecommunication devices such as telephone switches and network access facilities are maintained. These locations follow strict installation and operation requirements.

central processing unit

See processor.

channel associated signaling

A type of signaling that can be used on E1 circuit cards. It occurs on channel 16.

channel bank

An interface between analog telephone lines and digital telephone lines.

circuit card upgrade

A new circuit card that replaces an existing card in the platform. Usually the replacement is an updated version of the original circuit card to replace technology made obsolete by industry trends or a new system release.

clear to send

Located on Pin 5 of the 25-conductor RS-232 interface, CTS is used in the transfer of data between the computer and a serial device.

cluster controller

A bisynchronous interface that provides a means of handling remote communication processing.

code excited linear prediction

A means of encoding analog voice signals into digital signals that provides excellent quality with use of minimum disk space.


An instruction or request the user issues to the system software to make the system perform a particular function. An entire command consists of the command name and options.

complementary metal oxide semiconductor RAM

Memory which contains the platform's configuration information. CMOS RAM must have continuous power to preserve its memory, usually supplied by a lithium battery.


The arrangement of the software and hardware of a computer system or network. The system configuration includes either a standard or custom processor, peripheral equipment (for example, printers and modems), and software applications. Configuration also refers to the way in which the switch network is set up; that is, the types of products that are in the network and how those products communicate.

configuration management

The component of the system that allows you to manage the current configuration of voice channels, host sessions, and database connections, assign scripts to run on specific voice channels or host sessions, assign functionality to circuit cards, and perform various maintenance functions.

connect and disconnect (C and D) tones

DTMF tones that inform the system when the attendant has been connected (C) and when the caller has been disconnected (D).

connected digits

A sequence of digits that the system can process as a group, rather than requiring the caller to enter the digits one at a time.

controller circuit card

A circuit card used on a computer system that controls its basic functionality and makes the system operational. These circuit cards are used to control magnetic peripherals, video monitors, and basic system communications.


The ability of two products or services to operate and interact with each other on a single hardware platform.


An interactive utility for examining the operating system core and for determining if system parameters are being exceeded.

cron job

A list of one or more commands to a computer operating system or application server that are to be executed at a specified time. Each command is executed when its triggering time arrives.

Customer Relationship Management

A business strategy which helps companies get and care for customers.


An admonishment or advisory statement used in the system documentation to alert the user to the possibility of personal injury or death.


An electronic representation of information suitable for manipulation by a digital computer. Note that this is a more specialized version of the common definition.

data communications equipment

Standard type of data interface normally used to connect to data terminal equipment (DTE) devices.

data terminal equipment

Standard type of data interface normally used for the endpoints in a connection.

data terminal ready

A control signal sent from the data terminal equipment (DTE) to the data communications equipment (DCE) that indicates the DTE is on and ready to communicate.


A structured set of files, records, or tables.

database field

A field used to extract values from a local database and form the structure upon which a database is built.

database record

The information in a database for a person, product, event, and so on. The database record is made up of individual fields for each information item.

database table

A structure, made up of columns and rows, that holds information in a database. Database tables provide a means of storing information that changes too often to hard-code, or store permanently, in the transaction outline.


The channel that carries data for ISDN.


The process of locating and correcting errors in computer programs; also referred to as troubleshooting.


The way a computer performs a task in the absence of other instructions.


The process of performing diagnostics on a bus or on circuit cards.

dial pulse recognition

A method of recognizing caller pulse inputs from a rotary telephone.

dialed number identification service

A service that allows incoming calls to contain information about the telephone number for which it is destined.


Discrete data or signals such as 0 and 1, as opposed to analog continuous signals.

direct memory access

A quick method of moving data from a storage device directly to RAM, which speeds processing.


A type of file used to group and organize other files or directories.

dual tone multi-frequency

A touchtone sound that is an audio signal including two different frequencies. DTMF feedback is the process of the switch providing this information to the system. DTMF muting is the process of ignoring these tones (which might be simulated by human speech) when they are not needed for the application.

dump space

An area of the disk that is fixed in size and should equal the amount of RAM on the system. The operating system dumps an image of core memory when the system shuts down automatically. The dump can be fetched after rebooting to help in analyzing the cause of the shutdown.

dynamic random access memory (DRAM)

The readable/writable memory used to store data on the platform. Must be continually refreshed due to its inability to store data longer than a few milliseconds. However, the chips are relatively inexpensive to manufacture and so are worth managing.

Ear and Mouth

A common T1 trunking protocol for connection between two switches.

echo cancellation

The process of making the channel quiet enough so that the system can hear and recognize WholeWord, dial pulse, and Natural Language inputs during the prompt. See also barge-in.

EIA interface

A set of recommended standards developed by the Electrical Industries Association (EIA) that specifies various electrical and mechanical characteristics for interfaces between electronic devices such as computers, terminals, and modems. Also known as RS-232.

electrostatic discharge

Discharge of a static charge on a surface or body through a conductive path to ground. ESD can be damaging to integrated circuits.


Software on one operating system that imitates or reproduces the behavior of input and output on a different operating system.

Enhanced Serial Data Interface

A software-controlled and hardware-controlled method used to store data on magnetic peripherals.

Enterprise Communications Server

The telephony equipment that connects your business to the telephone network. Sometimes called a switch.

Error Correcting Mode

A means of reducing errors in facsimile (fax) transmission. If an error is received, then the receiver requests retransmission. Commonly referred to as ECM.

error message

A message on the screen indicating that something is wrong with the system, often with a suggestion of how to correct it.


Problems detected by the system during operation and recorded in the maintenance log. Errors can produce an alarm if they exceed a threshold.


A name for a local area network that follows IEEE Standard 802.3. Supported implementations are 10Baset and 100Baset.


1. A change in state that occurs at a particular time. 2. The notification given to an application when some condition occurs that is generally not encountered in normal operation.

event counter

A software device that tallies the number of times an event has occurred. If the number of times exceeds a configured amount, an action is taken.


1. A database field. 2. An area on a screen, menu, or report where information can be typed or displayed.


A collection of data treated as a basic unit of storage.

file system

A collection of related files (programs or data) stored on disk that are required to initialize a system.

file transfer

An option that allows you to transfer files interactively or directly to and from UNIX using the file transfer system (FTS).


Alphabetic characters used to identify a particular file.


Software that resides in ROM.


To set up a disk, floppy diskette, or tape with a predetermined arrangement of characters so that the system can read the information on it.


A packet (unit) of data used in data communications, which has a particular format that makes it easy to create and read. Frames typically consist of a header, payload, and trailer.

function key

A key, labeled F1 through F8, on your keyboard to which the system software gives special properties for manipulating the user interface.


How the system performs its functions.

hard disk drive (HDD)

A high-capacity data storage and retrieval device that is located inside a computer platform. A hard disk drive stores data on nonremovable high-density magnetic media based on a predetermined format for retrieval by the system at a later date.


The physical components of a computer system. The central processing unit, disks, tape and diskette drives, and so on, are all hardware.

hardware upgrade

Replacement of one or more fundamental platform hardware components (for example, the CPU or hard disk drive), while the existing platform and other existing optional circuit cards remain.


Part of a frame that typically identifies the contents, origin, and destination of the data.


A measurement of frequency in cycles per second. A hertz is 1 cycle per second.

host computer

A computer linked to a network to provide a range of services, such as database access and computation. The host computer operates in a time-sharing manner with other computers linked to it via the network.

I/O address

Input/output address.

I2C bus

Industry standard serial communication bus.

idle code

A code used in digital communications that represents an absence of data. Options include: 11111111, 01010100, and 01010101.

industry standard architecture

A PC bus standard that allows processors and other circuit cards to communicate with each other. In use for PCs prior to plug-and-play PCI technology.


The process of bringing a system to a predetermined operational state. The start-up procedure typically tests hardware, verifies the firmware load, and starts normal service.


A signal fed into a circuit or channel.

Integrated Services Digital Network (ISDN)

A network that provides end-to-end digital connectivity to support a wide range of voice and data services.


The access point of a system. The interface is designed to provide you with easy access to the software capabilities of the system.


The termination of voice and/or telephony functions when some condition occurs.

interrupt request

Within a PC, a signal sent from a device to the CPU to temporarily suspend normal processing and transfer control to an interrupt handling routine.

keyboard mapping

In emulation mode, this feature enables the keyboard to send 3270 keyboard codes to the host according to a configuration table set up during installation.

keyword spotting

A capability provided by WholeWord speech recognition and Natural Language Speech Recognition (NLSR) that allows the system to recognize a single word in the middle of an entire phrase spoken by a caller in response to a prompt.

line code

A replacement for strings of consecutive zeros in data transmission using pulse code modulation (PCM).

line side E1

A digital method of interfacing a system to a PBX or switch using E1-related hardware and software.

line side T1

A digital method of interfacing a system to a PBX or switch using T1-related hardware and software.

local area network

A data communications network in a limited geographical area. The LAN provides communications between computers and peripherals.

local database

A database residing on the system.


A UNIX system information and error logging process.


See logdaemon.

logging on/off

Entering or exiting the system software.

logical unit

A type of SNA network addressable unit.

magnetic peripherals

Data storage devices that use magnetic media to store information. Such devices include hard disk drives, diskette drives, and cartridge tape drives.

masked event

An event that an application can ignore (that is, the application can request not to be informed of the event).


A unit of memory equal to 1,048,576 bytes (1024 x 1024). It is often rounded to one million.


Options presented to a user on a computer screen or with voice prompts.


A method of data backup that allows all of the data transactions to the primary hard disk drive to be copied and maintained on a second identical drive in near real time. If the primary disk drive fails or becomes disabled, all of the data stored on it (up to 1.2 billion bytes of information) is accessible on the second mirrored disk drive.

Modified Modified READ

A method of data compression for facsimile (fax) transmission that encodes one scan line using information from other scan lines.


Dual tone digit signaling (similar to DTMF), used for trunk addressing between network switches or by network operators.

multithreaded application

A single process or application that controls several channels. Each thread of the application is managed explicitly. Typically this means state information for each thread is maintained and the state of the application on each channel is tracked.

nonindexed table

A table that can be searched only in a sequential manner and not via a field name.

nonmasked event

An event that must be sent to the application. Generally, an event is nonmaskable if the application is likely to encounter state transition errors by trying to ignore it.

null value

An entry containing no value. A field containing a null value is normally displayed as blank and is different from a field containing a value of zero.


An argument used in a command line to modify program output by modifying the execution of a command. When you do not specify any options, the command executes according to its default options.


A company that produces relational database management software. It is also used as a generic term that identifies a database residing on a local or remote system that is created and maintained using an ORACLE RDBMS product.


Part of a frame that contains the data of interest to the receiver.

peripheral (device)

Equipment such as printers or terminals that is in addition to the basic processor.

peripheral component interconnect

A newer, higher speed PC bus that is gradually displacing ISA for many components.

permanent process

A process that starts and initializes itself before it is needed by a caller.


A single basic sound of a particular spoken language. For example, the English language contains 40 phonemes that represent all basic sounds used with the language. The English word one can be represented with three phonemes, w - uh - n. Phonemes vary between languages because of guttural and nasal inflections and syllable constructs.


A set of one or more words used within an application. Examples include Thank you for calling XZY Business, One, and At the tone, press--.

platform migration

See platform upgrade.

platform upgrade

The process of replacing the existing platform with a new platform.


A term usually used with speech technologies, in particular standard speech, to indicate that a basic algorithmic technique has been implemented to accept one or more sets of parameters that tailors the algorithm to perform in one or more languages.


A message sent from a central controller to an individual station on a multipoint network inviting that station to send if it has any traffic.


A network arrangement whereby a central computer asks each remote location whether it wants to send information. This arrangement enables each user or remote data terminal to transmit and receive information on shared facilities.

Primary Rate Interface

An ISDN term for connections over E1 or T1 facilities that are usually treated as trunks.

private branch exchange

A private telephone switching system, either manual or automatic, usually serving an organization, such as a business or government agency, and usually located on the customer's premises.


In system documentation, the computer on which UnixWare and the system software runs. In general, the part of the computer system that processes the data. Also known as the central processing unit.

pseudo driver

A driver that does not control any hardware.

pulse code modulation

A digital modulation method of encoding voice signals into digital signals. Also called PCM.

read-only memory

A form of computer memory that allows values to be stored only once; after the data is initially recorded, the computer can only read the contents. ROM is used to supply constant code elements such as bootstrap loaders, network addresses, and other more or less unvarying programs or instructions.

Real Time Conferencing Protocol

An Internet protocol providing the ability to conference people together. Also known as RTCP.

Real-time Transport Protocol

An H.323 protocol for streaming media over IP. Also known as RTP.


See database record.


The process of using copies of the system software to reconstruct files that have been lost or damaged.

remote database

Information stored on a system other than your current system that can be accessed by the CONVERSANT system.


The process of recovering lost or damaged files by retrieving them from storage.

restore application

A utility that replaces a damaged application or restores an older version of an application.


The concept of using a component from a source system in a target system after a software upgrade or platform migration.

roll back

To cancel changes to a database since the point at which changes were last committed.

rollback segment

A portion of the database that records actions that should be undone under certain circumstances. Rollback segments are used to provide transaction rollback, read consistency, and recovery.

scan line

The region of a document read during a single pass of a digitizing device.

screen pop

A method of delivering a screen of information to a telephone operator at the same time a telephone call is delivered. This is accomplished by a complex chain of tasks that include identifying the calling party number, using that information to access a local or remote ORACLE database, and pulling a form full of information from the database using an ORACLE database utility package.

single inline memory modules

A method of containing random access memory (RAM) chips on narrow circuit card strips that attach directly to sockets on the CPU circuit card. Multiple SIMMs are sometimes installed on a single CPU circuit card.

single-threaded application

An application that runs on a single voice channel.

small computer system interface

A disk drive control technology in which a single SCSI adapter circuit card plugged into a PC slot is capable of controlling as many as seven different hard disks, optical disks, tape drives, and so on.


The set or sets of programs that instruct the computer hardware to perform a task or series of tasks, for example, Solaris software and the system software.

software upgrade

The installation of a new version of software in which the existing platform and circuit cards are retained.


A contiguous sequence of characters treated as a unit. Strings are normally bounded by white spaces, tabs, or a character designated as a separator. A string value is a specified group of characters symbolized by a variable.

structured query language

A standard data programming language used with data storage and data query applications.


A software and hardware device that controls and directs voice and data traffic. A customer-based switch is known as a private branch exchange (PBX).

switch hook

The device at the top of most telephones that is depressed when the handset is resting in the cradle (in other words, is on hook ). The device is raised when the handset is picked up (in other words, when the telephone is off hook ).

switch hook flash

A signaling technique in which the signal is originated by momentarily depressing the switch hook.

switch network

Two or more interconnected telephone switching systems.

synchronous communication

A method of data transmission in which bits or characters are sent at regular time intervals, rather than being spaced by start and stop bits.


A format for sending faxes as e-mail.


See database table.

tag image file format

A format for storing and exchanging digital image data associated with fax modem data transfers and other applications. These files can be identified by the .tif extension.


The process of a caller interrupting a prompt, so the prompt message stops playing.

target system

The system to which you are upgrading (that is, your system as you expect it to exist after you upgrade).


A 10-mm (10BASE5) coaxial cable used to provide interLAN communications.


A 5-mm (10BASE2) coaxial cable used to provide interLAN communications.

time-division multiplex

A method of serving a number of simultaneous channels over a common transmission path by assigning the transmission path sequentially to the channels, with each assignment being for a discrete time interval.


Analog telecommunications using four-wire media.

token ring

A ring type of local area network that allows any station in the network to communicate with any other station.


The flow of information or messages through a communications network for voice, data, or audio services.


Part of a frame that helps the receiver of the data to recognize and deal with transmission errors.

transient process

A process that is created dynamically only when needed.


The process of locating and correcting errors in computer programs. This process is also referred to as debugging.


A physical connection carrying calls between two switches (whether they be PBXs or central office switches).

UNIX operating system

A multiuser, multitasking computer operating system originally developed by Bell Labs.

UNIX shell

The command language that provides a user interface to the UNIX operating system.

upgrade scenario

The particular combination of current hardware, software, application and target hardware, software, applications, and so on.


A measurement of how easy an application is for callers to use. The measurement is made by making observations and by asking questions. An application should have high usability to be successful.

User Datagram Protocol

Part of TCP/IP that lets applications communicate using datagrams. Also known as UDP.

vi editor

A screen editor used to create and change electronic files.


An XML (Extensible Markup Language) variant that is used to create voice response applications that run on voice browsers. Scripts may be created either with a VoiceXML 2.0 editor or with Avaya IVR Designer (recommended).


An admonishment or advisory statement used in the system documentation to alert the user to the possibility of equipment damage.

wink signal

An interruption of current to a busy lamp indicating that there is a line on hold.

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