AT&T MERLIN LEGEND Release 3.1 System Planning Manual page 368

Glossary
O
off-hook
off-premises
telephone
ones density
on-hook
OPT
OPX
out-of-band
signaling
P
parity
PassageWay Direct
Connect Solution
pass-through
PBX
GL–20
System Planning
A 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 .
Requirement for channelized DS1 service to the public
network that eight consecutive zeros cannot occur in a
digital data stream.
A 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 by 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)
Signaling that uses the same path as voice-frequency
transmission and in which the signaling is outside the
band used for voice frequencies.
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 to provide an interface
between a personal computer and the system.
Connection from the internal modem to an attached
IS II/IS III application on the system.
(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.