Technical data

distributed processing
The technology that enables the distribution throughout the network of computing
power and storage facilities to user work areas, such as offices, laboratories, or
machines on factory floors.
distributed system
A collection of computer systems, tied together by communications networks for
the purpose of sharing resources; end users do not need to be aware of the physical
location of the shared resources.
DNS
See Domain Name System.
domain
An organizational unit with administrative responsibility for naming networks or
hosts. An internet domain name consists of a sequence of names (labels) separated
by periods (dots); for example,
tundra.mpk.ca.us.
domain name
The name used to refer to a fully qualified domain or subdomain. For example,
in
cat.food.iams.com
,
food.iams.com
,
iams.com
,and
.com
are all domain
names. Each name specifies a different domain level.
Domain Name System (DNS)
A distributed database system that allows TCP/IP applications to resolve a host
name into a correct IP address.
dot address
See dotted-decimal notation.
dotted-decimal notation
The syntactic representation for a 32-bit integer that consists of four 8-bit numbers
written in base 10 with periods (dots) separating them; used to represent IP
addresses in the Internet, as in 192.67.67.20. Many Internet application programs
accept dotted-decimal notation in place of destination machine names.
downline loading
Transferring a copy of a system image from a load host to a target. Some systems,
such as DEC WANrouter systems and Compaq DECserver terminal servers,
automatically request a downline load of their image upon startup and reboot.
One of the functions of a TFTP server.
drift
Thechangeinaclock’stimerateoveraspecifiedperiod.
A measure, in Hertz per second, of how quickly the skew of a clock is changing.
See also skew.
dynamic adaptive routing
The automatic rerouting of traffic based on a sensing and analysis of current actual
network conditions; not including cases of routing decisions taken on predefined
information.
Dynamic Host Configuration Protocol
A superset of the BOOTP protocol that enables the automatic assignment of
IP addresses to clients on networks from a pool of addresses. The IP address
assignment and configuration occurs automatically whenever appropriate client
systems (workstations and portable computers) attach to a network. The TCP/IP
Services for OpenVMS implementation of DHCP is based on the JOIN product
by Competitive Automation.
Glossary–14