Instruction manual

MERLIN LEGEND Communications System Release 5.0
System Planning
555-650-112
Issue 1
June 1997
Glossary
Page GL--14
O
P
off-hook Telephone is said to be off-hook when the user has lifted
the handset, pressed the Speakerphone button to turn on
the speakerphone, or used a headset to connect to the
communications system or the telephone network.
off-premises
telephone
See OPT .
on-hook Telephone is said to be on-hook when the handset is hung
up, the speakerphone is turned off, and the user is not
using a headset to connect to the communications system
or the telephone network.
OPT (off-premises telephone) Single-line telephone or other
tip/ring device connected to the system via a 008 OPT
module in the control unit. Appears as an inside extension
to the system, but may be physically located away from the
system.
OPX (off-premises extension)
parity The addition of a bit to a bit string so that the total number
of ones is odd or even, used to detect and correct
transmission errors.
PassageWay
Direct Connect
Set of software applications that provides an interface
between a personal computer and an MLX telephone.
PBX (private branch exchange) Local electronic telephone
switch that serves local stations (for example, extensions
within a business) and provides them with access to the
public network.
PC personal computer
PCMCIA memory
card
(Personal Computer Memory Card International
Association memory card) See
memory card .
personal line Central office line/trunk that terminates directly at one or
more extensions. In
Hybrid/PBX mode , a personal line
cannot be part of a line/trunk
pool . Also called “DFT” (direct
facility termination).
PFT (Power Failure Transfer) Feature that provides continuity
of telephone service during a commercial power failure by
switching some of the system’s line/trunk connections to
telephones connected to specially designated extension
jacks.
phantom
extension
An extension that is not actually plugged into the system
but is used, for example, as a calling group member
covered by a
voice messaging system .