Lucent Technologies MERLIN LEGEND Release 7.0 System Planning Manual page 439

MERLIN LEGEND Communications System Release 7.0
System Planning 555-670-112
Glossary
Display Buttons
DLC
DNIS
Door Answering
Unit
DOS
Drop-and-Insert
Equipment
DS0
DS1
DSL
DSS
DTE
DTMF signaling
Buttons on an MLX display telephone used to access the
telephone's display.
Direct-Line Console . Telephone used by a system operator
to answer outside calls (not directed to an individual or a
group) and inside calls, to transfer calls, to make outside
calls for users with outward calling restrictions, to set up
conference calls, and to monitor system operation.
Dialed Number Identification Service . Service provided by
AT&T and MCI to route incoming 800 or 900 calls
according to customer-selected parameters, such as area
code, state, or time of call.
Device connected to a tip/ring jack and used at an
unattended extension or front desk.
Disk Operating System .
Device that can be installed between systems connected
by tandem PRI trunks or T1-Emulated tandem tie trunks to
allow fractional use of the facility—that is, use of fewer than
23 of the PRI B-channels or fewer than 24 of the T1
channels . In a PRI facility, the equipment must never drop
Channel 24, the D-channel . All channels must still be
programmed and all count towards the system maximum of
80 lines.
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.
Digital Subscriber Line . Digital Subscriber Line provides
full-duplex service on a single twisted metallic pair (2-wire)
at a rate sufficient to support ISDN Basic Rate Access.
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.
Issue 1
April 1999
GL-11