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.