| DAEMON |
A program
that runs automatically on a computer to perform a service for the operating
system. |
| DAEMON |
A UNIX
process that operates continuously and unattended to perform a service.
TCP/IP uses several daemons to establish communications processes and provide
server facilities. |
| DARPA |
(Defense
Advanced Research Project Agency, originally ARPA) The governmental body
that created the ARPANET for widespread communications. ARPANET eventually
became the Internet. |
| DATA CIRCUIT |
Terminating
Equipment (D CE) Terminal Equipment (DTE) to a network or serial line. A
modem is a DCE device. Also called Data Communications Equipment and Data
Circuit Equipment. |
| DATA ENCRYPTION
STANDARD |
(DES)
An encryption standard officially sanctioned in the U.S. |
| DATA LINK |
The part
of a node controlled by a data link protocol. It is the logical connection
between two nodes. |
| DATA LINK
PROTOCOL |
(DLP)
A method of handling the establishment, maintenance, and termination of
a logical link between nodes. Ethernet is one example of a Data Link Protocol. |
| DATA TERMINAL
EQUIPMENT |
(DTE)
The source or destination of data, usually attached to a network by DCE
devices. A terminal or computer acting as a node on a network is usually
a DTE device. |
| DATABASE |
An structured
way of storing data in an organized way, often described in terms of a number
of tables each made up of a series of records, each record being made of
a number of fields. |
| DATAGRAM |
A basic
unit of data used with TCP/IP. |
| DBM |
A UNIX
database format. |
| DEBUGGING |
The process
of tracking down errors in a program, often aided by examining or outputting
extra information designed to help this process. |
| DEDICATED
LINE |
A dedicated
phone line used for network communications. |
| DEFENSE
COMMUNICATIONS AGENCY |
(DCA)
The governmental agency responsible for the Defense Data Network (DDN). |
| DEFENSE
DATA NETWORK |
(DDN)
Refers to military networks such as MILNET and ARPANET and the communications
protocols (including TCP/IP) that they employ. |
| DES |
(Data
Encryption Standard) An algorithm developed by the U.S. government to provide
security for data transmitted over a network. |
| DESTINATION
ADDRESS |
The destination
device's address. |
| DIALUP |
A type
of connection where you use a modem to connect to another computer or an
Internet provider via phone lines. |
| DIGEST |
A form
of mailing list where a number of messages are concatenated (linked) and
sent out as a single message. |
| DIGITAL |
Type of
communications used by computers, consisting of individual on and off pulses.
Compare to analog. |
| DIRECTORY |
In most
computer file systems files are grouped into a hierarchical tree structure
with a number of files in each directory (the files are like the leaves
and the directories are like the branches of this tree). |
| DIRECTORY
HANDLE |
A link
between a Perl program and a directory that is created when the directory
is opened. |
| DIRECTORY
SYSTEM AGENT |
(DSA)
A program that accepts queries from a directory user agent (DUA). |
| DIRECTORY
USER AGENT |
(DUA)
A program that helps a user to send a query to a directory server. |
| DISTRIBUTED
COMPUTING ENVIRONMENT |
(DCE)
A set of technologies developed by the Open Software Foundation (0SF) supporting
distributed computing. |
| DISTRIBUTED
FILE SERVICE |
(DFS)
An Open Software Foundation (OSF) fileserver technology sometimes used with
TCP/IP. |
| DISTRIBUTED
MANAGEMENT ENVIRONMENT |
(DME)
A system and network management technology developed by the Open Software
Foundation (OSF). |
| DISTRIBUTED
PROCESSING |
When a
process is spread over two or more devices, it is distributed. It is usually
used to spread CPU loads among a network of machines. |
| DNS |
Domain
Name System. The system that translates between Internet IP address and
Internet host names. |
| DOD |
(Department
of Defense) A U.S. government agency that originally sponsored the ARPANET
research. |
| DOMAIN |
Highest
subdivision of the Internet, for the most part by country (except in the
U.S., where it's by type of organization, such as educational, commercial,
and government). Usually the last part of a host name; for example, the
domain part of ibm.com is .com, which represents the domain of commercial
sites in the U.S. |
| DOMAIN
NAME SYSTEM |
(DNS)
The system that translates between Internet IP address and Internet host
names. |
| DOMAIN
NAME SYSTEM |
(DNS)
A service that converts symbolic node names to IP addresses. DNS is frequently
used with TCP/IP. DNS uses a distributed database. |
| DOT ADDRESS |
A unique
number assigned to identify a host on the Internet (also called IP address
or dot address). This address is usually represented as four numbers between
1 and 254 and separated by periods, for example, 192.58.107.230. |
| DOTTED
DECIMAL NOTATION |
A representation
of IP addresses. Also called "dotted quad notation" because it
uses four sets of numbers separated by decimals (for example, 255.255.255.255). |
| DOUBLE
BYTE CHARACTER SET |
A character
set where alphanumeric characters are represented by two bytes, instead
of one byte as with ASCII. Double byte characters are often necessary for
Asian languages, which have more than 255 symbols. |
| DOWNLOAD |
Move a
file from a remote computer to your local computer. |
| DROP CABLE |
In Ethernet
networks it refers to the cable connecting the device to the network, sometimes
through a transceiver. |
| DUMB TERMINAL |
A terminal
with no significant processing capability of its own, usually with no graphics
capabilities beyond the ASCII set. |