MERLIN LEGEND Communications System Release 6.0
System Manager’s Guide
555-660-118
Issue 1
February 1998
Glossary
Page GL-11
E
DSL
(Digital Subscriber Line) A 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.
DSS
(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.
DTE
(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.
DTMF signaling
(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.
E&M signaling
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.
EIA
(Electronic Industries Association)
EIA-232-D
Physical interface, specified by the
EIA, that transmits and
receives asynchronous data at speeds of up to 19.2-kbps
over cable distances of 50 feet (15 m).
Electronic
Switching System
See
ESS.
endpoint
Final destination in the path of an electrical or
telecommunications signal.
ESF
(extended superframe format)
PRI framing format
consisting of individual frames of 24 eight-bit slots and one
signal bit (193 bits) in a 24-frame extended superframe.
ESS
(Electronic Switching System) Class of central office (
CO)
switching systems developed by Lucent Technologies in
which the control functions are performed principally by
electronic data processors operating under the direction of
a stored program.
expansion carrier
Carrier added to the control unit
when the basic carrier
cannot house all of the required
modules. Houses a power
supply module and up to six additional modules.
ExpressRoute
1000
Data communications device that allows connection
between an RS-232
DTE device and the control unit using
MLX extension jacks on the 008 MLX or 408 GS/LS-MLX
module.
