AT&T MERLIN LEGEND Release 3.1 System Manager's Manual page 403

Glossary
O
off-hook
off-premises
telephone
on-hook
OPT
OPX
P
parity
PassageWay Direct
Connect Solution
PBX
PC
PCMCIA memory card
personal line
GL–16
System Manager's Guide
Telephone is said to be off-hook when the user has lifted
the handset, pressed the Speaker button to turn on the
speakerphone, or used a headset to connect to the
communications system or the telephone network.
See OPT .
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.
(off-premises telephone) Single-line telephone or other
tip/ring device connected to the system via an 008 OPT
module in the control unit. Appears as an inside extension
to the system, but may be physically located away from
the system.
(off-premises extension)
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.
Set of software applications that provides an
interface between a personal computer and an
MLX telephone.
(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.
personal computer
Personal Computer Memory Card International
Association memory card) See memory card .
Central office trunk that terminates directly on one
or more telephones. In Hybrid/PBX mode , a
personal line cannot be part of a trunk pool . Also
called "DFT" (direct facility termination).