background
errors background errors
- Errors that occur during the normal
operation of the system. They generally
occur one at a time or a few at a time.
backup
backup - The provision, logical
or physical, of facilities to speed the
process of restart and recovery following
failure. Facilities may include duplicated
files of transactions, periodic dumping
of core or backing storage contents, duplicated
processors, storage devices, terminals,
telecommunications hardware or the switches
to effect a changeover.
band
band - (1) The range of frequencies
between two defined limits.
bandwidth
bandwidth - (1) The difference
between the top and bottom limiting frequencies
of a continuous frequency band. (2) Indicates
the information-carrying capacity of a
channel. Analog transmission usually expressed
in kHz or MHz; digital transmission, bps,
Mbps. Fiber-optic bandwidth is usually
given as its capacity to transmit information
in a specific time period for a specific
length. (e.g. 10 Mbps/KM.) (3) Expressed
in different measurements depending on
transmission type.
bar-code
scanner bar-code scanner -
(1) Optical character reader. A device
used to read bar-codes by means of reflected
light, such as the scanners that read
the Universal Product Codes on supermarket
products.
basic
telecommunications access method (BTAM)
basic telecommunications access method
(BTAM) - An access method that permits
read/write communications with remote
devices.
baud - (1) A unit of signaling
speed. (2) A unit of data transmission
speed measured in bits per second. [The
speed in baud is the number of discreet
conditions or signal elements per second.
If each event represents only one bit
condition, then baud is the same as bits
per second.]
baud
rate baud rate - A measure
of signaling speed in data communications
that specifies the maximum number of signal
elements transmitted each second. [Over
dial-up telephone lines, 300 and 1200
baud are most common. For most purposes,
at slow speeds, a baud rate is the same
as the speed in bits per second. Baud
rate is the same as bit rate if all bits
have the same length.]
Bell
Operating Company (BOC) Bell
Operating Company (BOC) - Any of the
22 local Bell telephone companies owned
by AT&T before divestiture. The independent
BOCs provide primary access to the interexchange
carriers. See RBOC.
BETA test - The stage at
which a new product is tested under actual
usage conditions. The purpose of beta
testing is to locate and correct potential
problems before consumer marketing begins.
Follows Alpha Testing.
bid
bid - (1) An attempt to gain
control over a line in order to transmit
data. (2) Usually associated with contention
style of sharing a single line among several
terminals. [Non-uniform time-outs at each
terminal for reinstituting a bid if the
line is busy give assurance that each
terminal can have access to the line.
billed
telephone number (BTN) billed
telephone number (BTN) - The
"main number" of a customer's
service that the LEC uses as a customer's
account number. It is usually also an
actual ANI. Will generally have WTNs associated
with it. Every separate, distinct phone
bill a customer gets will generally have
a separate BTN.
billing
cycle billing cycle - A
recurring period of time between traffic
cut-off dates which precedes customer
billing. Cycles are typically 30 days.
binary
binary - A number system
based upon twos rather than tens and that
uses only two characters, zero (0) and
one (1).
binary
digit binary digit - Unit
of information in two-level digital notation
which may be 0 or 1. A member selected
from a binary set.
binary
synchronous transmission (BSC or bisync)
- (1) Data transmission in which synchronization
of characters is controlled by timing
signals generated at the sending and receiving
stations. (2) A half-duplex, character-oriented
data communications protocol. Contrast
with asynchronous transmission.
bipolar
bipolar - Literally, having
two poles. An input signal is bipolar
when one electrical voltage polarity represents
a logically true input and its opposite
polarity represents a logically false
input. Contrast with unipolar.
bit
bit - (1) The smallest unit of
coded information. (2) A pulse whose presence
or absence indicates data. Abbreviation
for binary digit.
bit
duration bit duration -
(1) Equivalent to the time that it takes
one encoded bit to pass a point on the
transmission medium. (2) In serial communications,
a relative unit of time measurement used
for comparison of delay times where the
data rate of a transmission channel can
vary (for example propagation delay, access
latency).
bit
rate bit rate - The rate
at which bits (binary digits) are transmitted
over a communications path. Normally expressed
in bits per second (bps). [The bit rate
is not to be confused with the data signaling
rate which measures the rate of signal
elements being transmitted.]
bit
transfer rate bit transfer
rate - The number of bits transferred
per unit time, usually expressed in bits
per second (bps).
bit-oriented
bit-oriented - Describes a communications
protocol or transmission procedure where
control information is encoded in fields
of one or more bits; oriented toward full-duplex
link operation.
bit
map bit map - A matrix
of dots, all of the same density, that
form an image.
bits
per second (bps) bits per second
(bps) - The rate at which data transmission
(binary digits) is measured. See bit rate.
black
box black box - A generic
term used to identify functional equipment
segments, as opposed to circuitry, that
make up each segment of a telecommunications
system.
block
block - A string of records,
words or characters treated as a logical
entity. Blocks are separated by interblock
gaps, and each block may contain one or
more records.
block
error rate test (BLERT) block
error rate test (BLERT) - (1) In data
communications testing, the ratio between
the total number of blocks transmitted
in a given message and the number of blocks
in that message received in error. (2)
A measure of the quality of a data transmission.
block
length block length - A measure
of the size of a block, usually specified
in units such as records, words, computer
words or characters.
blocked
calls blocked calls - All attempted
calls that are not connected. Two most
common reasons for non-connections: all
lines to the central offices are in use;
all connecting paths through the PBX/switch
are in use.
blocking
blocking - (1) Engineering principle
involving average time a user will wait
while a call searches for the most economical
route; opposed to queuing where a call
waits for the most economical route. (2)
Inability to establish a new call because
of the inaccessibility of facilities in
the system being called. Measured under
grade of service using "P" factor.
Bell
Operating Company (BOC) Bell Operating
Company (BOC) - Another name for
the LEC, "baby bell" or local
phone company.
bomb
bomb - To fail or crash.
booting
booting - Technique for loading a
program into a computer's memory in which
the program's initial instructions direct
the loading of the rest of the program.
Usually, a few manual instructions must
be entered on a keyboard, or a switch
implemented to initiate the process.
bootstrap
loader bootstrap loader - An input
routine in which simple preset computer
operations are used to load instructions
that in turn cause further instructions
to be loaded until the complete computer
program is in storage. [The term refers
to the system "pulling itself up
by its bootstraps."]
break
break - (1) To interrupt the sending of
a message and take control of the circuit
at the receiving end. (2) An interruption
in continuity.
breakout
box breakout box - A device that allows
access to individual points on a physical
interface connector for testing and monitoring.
breakout
panel breakout panel - A breakout
box mounted as a component in some larger
device.
bridge,
bridging bridge, bridging - Equipment
and techniques used to match circuits
to each other ensuring minimum transmission
impairment. [Bridging is normally required
on multipoint data channels were several
local loops or channels are interconnected.
broadband
- (1) A transmission facility having a
bandwidth of greater than 20 kHz and,
therefore, capable of higher-speed data
transmission. (2) Analog transmission
technique used with data and video transmissions
that provides multiple channels for users
through frequency division multiplexing.
broadcast
- Transmission to a number of receiving
locations simultaneously.
browser
- browser - Software used to access
the web network, e.g., Netscape or Internet
Explorer.
buffer
buffer - (1) A high-speed area of storage
that is temporarily reserved for use in
performing the input/output operation
into which data is read or from which
data is written. (2) Used to accumulate
data into blocks of sufficient size to
be handled efficiently by a processor
or terminal. Synonym: I/O area.
bug
bug - (1) A mistake or malfunction. (2)
A program defect or error. [In 1946 Grace
Hopper detected a problem with an Eniac
computer at the University of Pennsylvania.
Investigation uncovered an insect lodged
within the computer causing the malfunction.
Hopper's exclamation, "There's a
bug in the computer," coined a new
word for computer error.]
bulletin
board bulletin board - An electronic
message center accessible through computer-aided
communication lines.
burst
burst - A sequence of signals in data
communications counted as one unit in
accordance with some specific criterion
or measure.
burst
errors burst errors - Bits or signals
lost due to such problems as line switching
or multiplex switching. [Typically involves
a few thousand errors or lost bits at
a time.]
bus
bus - (1) A heavy conductor, or group
of conductors, to which several units
of the same type of equipment may be connected.
(2) A path or channel for transmitting
electrical signals and data, usually between
a computer and peripheral equipment.
busy
busy - Call condition in which transmission
facilities are already in use. Synonym:
off-hook condition.
busy
hour busy hour - (1) The peak 60 minutes
during a business day when the largest
volume of communications traffic is handled.
(2) When phone lines are most in demand
and/or most used.
busy
tone busy tone - A single tone that
is interrupted at 60 ipm (impulses per
minute) rate to indicate that the call's
terminating location is already in use.
bypass
bypass - When a customer avoids using
the LEC to connect to their long distance
carrier
byte
- (1) The representation of a character.
(2) A group of eight bits makes a byte.
Typically a 16-bit "word" is
itself divided into two bytes for handling.
(3) Unit of measurement used to rate storage
capacity of disks; usually the smallest
addressable unit of information in a data
store or memory. One thousand bytes is
a kilobyte; one million bytes is a megabyte.
C
C
band C band - A portion of the electromagnetic
spectrum used heavily for satellite and
microwave transmission; frequencies of
approximately 4 to 6 GHz.
cache
memory cache memory - A high-speed,
buffer-type memory filled at medium speed
from the main memory. [Programs and instructions
found in the cache memory can be operated
at higher speeds without the necessity
of loading another segment.]
call-by-call
selection call-by-call selection -
The ability to switch calls to individual
trunks, rather than trunk groups, and
to transmit necessary information to the
specific trunk-type necessary to complete
the call.
call
detail record (CDR) - Computer record
containing data unique to a specific call.
[This information is processed as a unit
and contains such details as originating
switch, terminating switch, call length
and time of day.] (2) Processing of call-specific
information -- start time, elapsed time,
number dialed, date, and other pertinent
customer data
call
forward/with reason display call forward/with
reason display - Enables the called number,
during an internodal call, to forward
the incoming call to an alternate destination
and provide a message explaining why the
call is being forwarded.
calling
name delivery calling name delivery
- Provides the ability during call setup
to deliver the name of the calling party
from the originating to the terminating
switch or the name of the connected party
from the terminating to originating switch.
camp (or camp-on) - A PBX feature
where a telephone line is busy and the
incoming call is placed in a waiting mode
until the line is available, at which
time the call is automatically put through.
canned
program canned program - A software
program written to meet the expected customer
needs of a certain application. Opposite
of custom programs.
capability
capability - Data processing equipment
characteristic by which one machine may
accept and process data without conversion
or code modification.
carrier
carrier - (1) A company authorized
by appropriate regulatory agencies to
provide communications services. (2) A
continuous frequency capable of being
modulated or impressed with a second information
carrying signal.
carrier
modulation carrier modulation - A
signal at some fixed amplitude and frequency
which is combined with an information
bearing signal in the modulation process
to produce and output a signal suitable
for transmission.
carrier
system - A method for providing several
communications channels over a single
path. Accomplished by modulating the data,
voice or video transmissions onto a higher
frequency carrier wave, then recovering
it at the receiving end through a process
of demodulation (See Frequency Division
Multiplexing.)
categories
of service categories of service -
Basic and enhanced, as defined by the
Federal Communications Commission (FCC).
[Basic service refers to transmission
capacity for the movement of information;
for example residential telephone service.
Enhanced service combines basic service
with computer processing; for example
Electronic Yellow Pages.]
cathode
ray tube (CRT) cathode ray tube (CRT)
- A vacuum tube display in which a beam
of electrons can be controlled to form
alphanumeric characters or symbols on
a luminescent screen, for example, by
use of a dot matrix.
cellular
mobile radio cellular mobile radio
- A radio-based system providing exchange
telephone service to a station located
in an auto or other mobile vehicle or
device (for example briefcase). [Radio
circuits transmitted to/from a base radio
station cover a specific geographical
area. As the vehicle or device moves from
one area to another, different base radio
stations handle the call.]
central
office (CO) central office (CO) -
(1) Location of telephone switching equipment
where customers' lines are terminated
and interconnected. (2) Switching center
that provides local access to the public
network. Sometimes referred to as: End
Office, Local Dial Office, Wire Center
or Switching Center.
CENTREX
CENTREX - A type of private branch
exchange service where incoming calls
may be dialed direct to extensions without
operator assistance. Outgoing and intercom
calls may be dialed by extension users.
CENTREX,
CO CENTREX, CO - Arrangement in which
the Local Exchange Company's service-providing
switch is located in its central office.
CENTREX,
CU CENTREX, CU - Arrangement in which
the PBX features are provided by a switching
system located on the customer's premises,
but work under the control of, or in conjunction
with, equipment located in a LEC central
office.
channel
channel - (1) The smallest subdivision
of a transmission system by means of which
a single type of communication service
is provided, for example, a voice channel
or a data channel. (2) A communications
path via a carrier or microwave radio.
(3) In data communications, a path for
electrical transmission between two or
more points. (4) Within a computer, the
electronic paths along which data flows
between the input-output units of a computer
and the customer premises equipment (CPU).
Synonym: circuit, facility, line, link
or path.
channel
bank channel bank - (1) A part of
the carrier system that performs the first
step of modulation. (2) A multiplexer
that modulates a group of channels into
a higher frequency band and, conversely,
demultiplexes the higher frequency band
into individual channels. It can break
a signal into the equivalent of 24 analog
voice grade and/or 56 Kbps digital channels.
channel
capacity - The maximum bit rate that
can be handled by a channel.
channel
mileage charge - Monthly leased rate
for circuits between telephone company
(telco) central offices.
channel
service unit (CSU) channel service
unit (CSU) - Premises equipment that complies
with Bell Technical Publication 62411
in providing loopback, keep-alive signals,
alarm and status conditions.
channel
termination charge - Fee associated
with a T1 for the circuits feeding into
a telco central office.
channel,
four-wire channel, four-wire - A two-way
circuit, each with backup, where the signals
simultaneously follow separate and distinct
paths in opposite directions in the transmission
medium.
character
character - (1) Any alphabetical letter,
digit or special symbol. (2) In data transmission,
the representation of a letter number
or symbol by a specific code made up of
binary digits.
character-oriented
character-oriented - A communications
protocol or transmission procedure that
carries control information encoded in
fields of one or more bytes.
chips
chips - Miniaturized microprocessors
built on a single piece of silicon. [Typically,
less than 1/2-inch square, they contain
all the essential elements of a central
processor, including the control logic,
instruction decoding and arithmetic processing
circuitry. Microprocessor chips are combined
with memory and I/O integrated circuit
chips to form a microcomputer, which usually
fill no more than a single printed circuit
board.]
circuit
circuit - A path for the transmission
of electromagnetic signals; includes all
conditioning and signaling equipment.
Synonym: facility.
circuit
grade circuit grade - (1) The information-carrying
capability of a circuit, delineated in
speed or signal type. (2) For data use,
capability within certain speed ranges.
circuit
switching circuit switching - (1)
A method of communications, where an electrical
connection between calling and called
stations is established on demand for
exclusive use of the circuit until the
connection is released. (2) A switching
system that completes a dedicated transmission
path from sender to receiver at the time
of transmission. See also: packet switching,
store and forward, message switching.
class
of service (COS) - (1) Telephone service
distinctions which include: rate differences
between individual and party lines, flat
rate and message rate, and restricted
and extended area service. (2) A subgrouping
of telephone customers or users for the
sake of rate distinction or limitation
of service.
clock
clock - A repetitive signaling device
used to control a synchronous computer.
cluster
controller cluster controller - A
device that handles the remote communications
processing for multiple terminals or workstations.
coaxial
cable coaxial cable - Cable consisting
of an outer conductor surrounding an inner
conductor, separated from each other by
insulating material. It can carry a much
higher bandwidth than a wire pair.
CODEC
CODEC - Equipment containing a coder plus
a decoder. Used to convert analog signals
to digital form for transmission over
a digital medium and back again to the
original analog form.
cold
boot cold boot - (1) First software
initialization of the computer. (2) Software
loading and checking just after the computer
has been turned on.
color
graphics adapter (CGA) color graphics
adapter (CGA) - Equipment which provides
200 vertical x 600 horizontal pixel resolution
for digital (rather than analog) video
signals.
column
column - Vertical arrangement of characters.
common
carrier common carrier - Government-regulated,
private company that furnishes the general
public with telecommunications services
and facilities; for example, a telephone
or telegraph company.
common
channel interoffice signaling (CCIS)
common channel interoffice signaling (CCIS)
- A method in which labeled messages convey
signaling and call completion information
over a single circuit, leaving other circuits
free for voice, data or video transmissions.
common control switching arrangement
(CCSA) - Network service that directs
inward and outward dialing typically with
a seven-digit code. Originally designed
as a feature for private networks. Now
seen in virtual switched private line
networks.
common
control switching 7 (CCS7) common
control switching 7 (CCS7) - A digital
communications channel dedicated for the
processing of signaling and call setup
information between processors in the
switched network. (2) An international
standard for network signaling via data
links operating at 56 kbps.
common
intermediate format (CIF) common intermediate
format (CIF) - The type of coded video
frame transmitted when using CCITT recommendation
H.261 coding methods. CIF is 30 frames
per second, 325H x 288V pixels.
communication
communication - Transmission of intelligence
between two points (origin and reception)
without alteration of sequence or structure
of the information content. See also data
communication.
Communications
Satellite Corporation (COMSAT) Communications
Satellite Corporation (COMSAT) - A United
States company created by an act of Congress
in 1962 to provide communications via
satellites. COMSAT leases satellite circuits
to many American companies and is active
in international communications through
partial ownership in the International
Telecommunications Satellite Organization
(INTELSAT) and the International Maritime
Satellite Organization (INMARSAT).
communications
terminal communications terminal -
Any device which generates or receives
electrical or tone signals that can be
transmitted over a communications channel.
component
video signal - Transmission in which
the red (R), green (G) and blue (B) picture
components are present as individual bits
of information. [Synchronization information
may be included with the G signal or be
separate.]
composite
video signal composite video signal
- Transmission incorporating luminance,
color and synchronizing information.
compression
compression - Techniques to reduce the
number of bits required to represent information
in data transmission or storage, thereby
conserving bandwidth and/or memory. (2)
Application technique.
continuous
presence continuous presence - A video
processing, transmission and display mode
that involves combining parts of two separate
video images for transmission in a single
data stream.
CompuServe
CompuServe - An information retrieval
service which operates primarily in a
videotex-like mode but also allows for
standardized time-sharing as well as bibliographic
and numeric retrieval. See: videotex
computer
computer - A device capable of solving
problems or manipulating data by accepting
data, performing prescribed operations
on the data and supplying the results
of these operations. Various types of
computers are: analog computer, digital
computer, calculator.
computer-aided
design (CAD) computer-aided design
(CAD) - Automation of the performance
of various operations according to graphic
design specifications through the use
of a special computer and peripherals.
computer-aided
manufacturing (CAM) computer-aided
manufacturing (CAM) - Automation of the
performance of various operations according
to manufacturing specifications through
the use of a special computer and peripherals.
computer-assisted
instruction (CAI) computer-assisted
instruction (CAI) - An application in
which a stand-alone personal computer
or system is used to teach. Applications
usually involve a dialog between students
and software programs which inform students
of their mistakes in a real-time manner.
computer
science computer science - The study
of computer hardware and software.
concatenation
- (1) To unite in a series; to link
together; to chain. (2) The linking of
transmission channels (phone lines, coaxial
cable, optical fiber) end-to-end.
conditioning
conditioning - (1) To bring to a standard.
(2) Addition of equipment to voice grade
lines to provide for data transmissions
at specified minimum values of line characteristics,
in ranges from C1 to C4 (the best). [Common
carriers often recommend no conditioning
for lines transmitting at 1200 baud; C1
for 2400 baud, C2 for 4800 baud and C4
for speeds above 4800 baud.]
conference
call conference call - A connection
established among three or more stations
in such a manner that each of the stations
is able to communicate with all the others.
configuration
configuration - The interconnection and
programming of independent machines or
equipment to operate as a system.
contention
contention - Condition on a communications
channel or in a peripheral device when
two or more stations try to either transmit
at the same time or access a resource
simultaneously.
control
unit (CU) control unit (CU) - Central
processor of a telephone switching device.
Consultative
Committee on International Telegraph and
Telephone (CCITT) Consultative Committee
on International Telegraph and Telephone
(CCITT) - An internationally recognized
advisory group that recommends worldwide
standards for common-carrier communications
services.
conversational
mode - Operation of a data processing
system in which a sequence of alternating
entries between a user and the system
takes place in a manner comparable to
a conversation between two persons.
counter
counter - Device which tallies the number
of occurrences of an event (example, a
cash register) .
country
code country code - A one-, two- or
three-digit number used for international
dialing. [The first digit is always the
world-zone number. Subsequent digits further
define the geographic area.]
crash
crash - Breakdown resulting from either
a software or hardware malfunction.
crosstalk
crosstalk - Transmission noise caused
by energy "leaking" from one
channel to another on the same facility.
[In analog voice communications, crosstalk
makes conversation on one circuit accidentally
audible on another.]
current
loop current loop - Transmission technique
that recognizes current flows, rather
than voltage levels. [Traditionally used
in teletypewriter networks, incorporating
batteries as the transmission power source.]
cursor
cursor - Position indicator frequently
employed in terminals or workstations
to indicate where a character is to be
corrected or data is to be entered.
customer
information system (CIS) customer
information system (CIS) - The Telco database
which holds customer information such
as service and product orders, installation
dates, features used or invoice history.
This information is pulled by IPS and
other billing systems.
customer
owned and maintained (COAM) customer
owned and maintained (COAM) - User provided
and serviced communications equipment
and its associated wiring.
customer
premises equipment (CPE) customer
premises equipment (CPE) - All telecommunications
equipment (except pay phones) and, usually,
wiring that is located at the users building.
customer
service customer service - A department
in an organization that provides outbound
services such as: technical assistance,
help lines, product or account information,
location of dealers, emergency responses,
service information or complaint handling.
cut
- (1) Transfer of a service from one
facility to another. (2) Process of moving
from a test environment into full production.
(3) Implementation of a system in a continuous,
time bound manner.
cut
through cut through - Establish a
complete path for signaling and/or audio
communications.
cyclic
redundancy check - Error detection technique.
[Using a polynomial, a series of two eight-bit
block check characters are generated that
represent the entire block of data. The
block check characters are incorporated
into the transmission frame, then checked
at the receiving end.]
D
D4 framing format
D4 framing format - (1) Division of DS1-level
circuit into 24 equal channels. [Each
channel carrier digitizes voice and signaling
information in eight-bit bytes. A D4 frame
consists of 192 (8 X 24) information bits.
In addition, to identify each of the 24
channels, a framing bit is added in the
193rd position. Each byte is updated 8,000
times per second. Thus, the transmission
speed of a DS1 circuit is 1,544,000 Hz
(193 X 8,000).] (2) Monitors the DS1 signals
for either framing errors or bipolar violations
(BPVs). BPVs are eliminated when the bit
stream passes through interfaces such
as a multiplexer, Automatic Protection
Switch or the Digital Cross-Connect System
(DCS). Since no end-to-end performance
monitoring is available using BPVs, the
line must be taken out of service to test
for large errors.
daisy
chain daisy chain - Connection of
multiple devices in a serial fashion.
[An advantage of daisy chaining is a savings
in transmission facilities. The disadvantage
is that if a device malfunctions, all
other devices daisy-chained behind it
are disabled.]
data
data - (1) Units of information. (2)
Any representation, such as characters
or analog quantities, to which meaning
is or may be assigned.
data
above voice (DAV) data above voice
(DAV) - Transmission system which carries
digital data on a portion of the microwave
radio spectrum above the frequency used
for voice transmission.
data
access arrangement (DAA) data access
arrangement (DAA) - Communication equipment
furnished by a common carrier that allows
attachment of privately owned data transmission
equipment (DTE) to the common carrier
network.
data
communications data communications
- (1) Transfer of information between
a source and a destination via one or
more data links, according to appropriate
protocols. (2) Transmission and reception
of data, often including operations such
as coding, decoding and validation.
data
conversion data conversion - Process
of changing information from one form
of representation to another.
data
coupler data coupler - A device to
connect customer-owned modems or data
sets to the regular telephone network.
It functions by limiting the power applied
to the line and providing network control
and signaling.
data
encryption standard (DES) data encryption
standard (DES) - A cryptographic algorithm
designed by the National Bureau of Standards
to encipher and decipher data using a
64-bit key.
data
pbx data pbx - A digital switch that
allows a user on an attached circuit to
select from other circuits, usually one
at a time and on a contention basis, for
the purpose of establishing a through
connection. [A data PBX is distinguished
from a PBX in that only digital transmission,
and not analog, is supported.]
database
database - An organized compilation of
computerized bits. [Formalized rules exist
for the establishment, control and access
of a database.]
datalink
control datalink control - Second
layer in the International Standards Organization
reference model for Open Systems Interconnection
(OSI). Synonym: protocol.
Datapac
Network Datapac Network - A common
user, packet-switched data network provided
by The Computer Communications Group of
the Trans Canada Telephone System.
dataphone
dataphone - (1) A generic term to
describe a family of devices to facilitate
data communication. (2) An AT&T designation
for a service which provides data communication
over telephone facilities.
dataphone
digital service (DDS) dataphone digital
service (DDS) - A communications service
of the Bell System in which data is transmitted
in digital rather than analog form, thus
eliminating the need for modems. See acronym
list for other uses of DDS.
data
terminal equipment (DTE) data terminal
equipment (DTE) - (1) Provides for the
communications control function (protocol).
(2) Any piece of equipment at which a
communications path begins or ends.
deadlock
deadlock - Unresolved contention for
the use of a resource.
debug
debug
