AT&T MERLIN LEGEND Installation & Maintenance Manual page 705

Glossary
robbed-bit signaling (RBS)
Signaling in which the least
significant bit (LSB) of every
sixth frame per channel is
used for signaling in that
channel.
ROM (read-only memory)
Computer memory that can
be read but cannot be
changed.
RS-232
A physical interface,
specified by the EIA
(Electronics Industries
Association), that transmits
and receives asynchronous
data at speeds of up to 19.2
kbps over cable distances of
50 feet.
S
signaling
The sending of control and
status information between
devices to set up, maintain,
or take down a connection.
simplex signaling
The transmission of signals in
one direction only across a
telecommunications channel.
Glossary
GL-20
single-line telephone
An industry-standard, touch-
tone or rotary telephone that
only handles one line/trunk
and is connected to the
communications system via a
jack on a basic telephone
module.
SMDR printer
A printer used for Station
Message Detail Recording
(SMDR) that is connected to
the communications system
via an RS-232 jack on the
processor module.
Software Defined Network
(SDN)
An AT&T private networking
service created by
specialized software within
the public network.
special character
A pause, stop, or end-of-
dialing signal in a
programmed dialing
sequence such as an Auto
Dial or Personal Speed Dial
number.
Square Key
A way of configuring the
communication system in Key
mode so that all lines appear
on all telephones.