AT&T MERLIN LEGEND Release 3.0 System Programming Manual page 792

Glossary
DLC
DNIS
door answering unit
DOS
DSO
DS1
DSS
DTE
DTMF signaling
E
E&M signaling
EIA
GL–10
System Programming
(Direct-Line Console) Telephone used by a system
operator to answer outside calls (not directed to an
individual or a group) and inside calls, transfer calls, make
outside calls for users with outward calling restrictions, set
up conference calls, and monitor system operation.
(Dialed Number Identification Service) Service provided
by the AT&T Switched Network (ASN); it routes incoming
800 or 900 calls according to customer-selected
parameters, such as area code, state, or time of call.
Device connected to a basic telephone jack and used at
an unattended extension or front desk.
(disk operating system)
(Digital Signal 0) Single 64-kbps voice or data channel.
(Digital Signal 1) Bit -oriented signaling interface that
multiplexes twenty-four 64-kbps channels into a single
1.544-Mbps stream.
(Direct Station Selector) 60-button adjunct that enhances
the call-handling capabilities of an MLX-20L or MLX-28D
telephone used as an operator console.
(data terminal equipment) Equipment that makes the
endpoints in a connection over a data connection, for
example, a data terminal, personal computer, host
computer, or printer.
(dual-tone multifrequency signaling) Touch-tone signaling
from telephones using the voice transmission path. DTMF .
signaling provides 12 distinct signals, each representing a
dialed digit or character, and each composed of two
voiceband frequencies.
Trunk supervisory signaling, used between two
communications systems, in which signaling information is
transferred through two-state voltage conditions (on the
Ear and Mouth leads) for analog applications and through
two bits for digital applications. See also tie trunk.
(Electronic Industries Association)