AT&T DEFINITY 2500 Instruction Manual page 234

CHAPTER 5. GLOSSARY
Designated ?elephone/voiceTerminal
The specific telephone/voice terminal to which calls, for
a
certain extension, are redirected.
Oial-Fep€aling
Tre
Trunk
A
telecommunications channel belween
two systems. The
number dialed
is
repeated or
dialed in at lhe distart
end.
Dial
Tone
A
continuous steady
tone-indicates
that dialing may begin or a feature may be activated.
Dialing
Plan
The valid numbers assigned wilhin a
system
to
gain access to
leatures,
trunk groups,
or
telephones/voice terminals.
oigital
Data
Dala transmitted
in
the form
of
digits.
Digats
are
assigned numerical values,
and
the
information content
of
the signal is only
concerned with
the discrete states ot the
signal
(dual-state condition: on/off, open/closed, and truefialse).
Oigital
Trunt
A
circuit
in a
teiecommunications channel designed
to
handle digital transmission of
information as opposed to analog.
Oirect Daslance Dialing (DlD)
Long
distance calls completed without operator assistance.
Direct lnward Dialing (DlD)
Trunk
An incoming trunk used tor
dialing directly into
a switching system without assistance trom
lhe
attendant-
Disrributed communicaiion System (DCS)
A
nlrmber
of
systems connected together in
a
network conliguration
to
serve
a
customer
with a large
number
of
lines. Systems can be in the same equipment room, in
a
campus
arrangement separated
by
short
distances,
or
scattered around
a
metropolitan
area.
Attendant and voice terminal tealures can be used across tie trunks
ancl
data links to allow
the multisystem to appear as one systen.
5-5