MERLIN LEGEND Communications System Release 6.0
System Programming
555-660-111 Issue 1
February 1998
Glossary
PageGL-28
V
UPS (uninterruptible power supply) Device that connects to the
system to provide 117 VAC to the equipment when the
commercial power source fails.
VAC (alternating-current voltage)
VDC (direct-current voltage)
VMI (voice messaging interface) An enhanced
tip/ring
port.
videoconferencing
system System application that allows face-to-face meetings, with
voice and video, to occur between individuals or groups.
This application requires high-speed data transmission
facilities. See a lso
desktop videoconferencing
and
group
videoconferencing.
virtual private
network See
VPN
.
VPN (virtual private network) A type of
private network
that uses
the switching capabilities of the
PSTN
, rather than
tandem
switching
, to direct calls between connected
communications systems. A VPN may constit ute a p a r t of a
private network.
voice-band
channel A transmission channel, generally in the 300–3400-Hz
frequency band.
voice mail Application that allows users to send messages to other
system extensions, forward messages received with
comments, and reply to messages.
voice messaging
interface See
VMI
.