Altigen AltiWare OE 4.0, Administration Manual

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Glossary
212 AltiWare OE System Administration Manual
option - a selection from several possibilities.
OSI - Open Systems Interconnection. A software model defined by the
International Standards Organization that standardizes levels of service and types
of interaction for networked computers. The OSI reference model defines seven
layers of computer communication and what each layer is responsible for.
overlap dialing - dialing scheme that allows the terminal to omit part of the digits
required to complete a call, while the remaining digits are buffered.
P
PABX - Private Automatic Branch Exchange. A private branch exchange (PBX)
that provides access to and from the public telephone network without operator
intervention.
PBX - Private Branch Exchange. A switching system providing telephone
communications between internal stations and external networks.
PCM - Pulse Code Modulation.
physical extension - is associated with a physical port and device. An extension is
created, by default, as a physical extension (as opposed to a virtual or workgroup
extension) unless there are no more physical ports available.
pilot number - the extension number that identifies a workgroup or distribution
group.
POP3 - Post Office Protocol version 3. Protocol for retrieving e-mail by remote
client.
port - a communication channel through which a client process communicates with
a protected subsystem.
POSIX - an acronym defined as “a portable operating system interface based on
UNIX”, refers to a collection of international standards for UNIX-style operating
system interfaces. In the mid-to-late 1980’s, government agencies began specifying
POSIX as a procurement standard for government computing contracts.
Power Failure Backup - If your AC power fails, your telephone system can still
operate by switching to a backup battery power supply, often called an
(Uninterrupted Power Supply) UPS.
Power Failure Transfer - A telephone system feature. When the commercial AC
power fails and there is no backup power source such as a battery or a generator,
this feature switches some of the trunks connected to the telephone system to
several single line phones that do not need external power and can draw their power
from the telephone lines.
Power Supply - the part of the telephone system or a computer that converts the
normal 120 or 240 volts AC power to AC and DC at the various voltages and
frequencies as needed by various components and circuits of the system.