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Polycom RMX DOC2579D User Manual

Page 157

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Polycom RMX 1500/2000/4000 Getting Started Guide

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DTMF

Dual Tone Multi Frequency. A system of coded signals
used by touch-tone telephones in which a specific sound,
frequency or tone is assigned to each key so that the
signal can be easily recognized by a computer. The codes
enable data input and control of voice-processing
systems. DTMF signals can pass through the entire
connection to the destination device and therefore are
used for remote control after the connection with the MCU
is established.

E1 Line

A 2Mb digital switched line used in Europe.

Endpoint

A hardware device, or set of devices, that can call, and be
called by an MCU or another endpoint. For example, an
endpoint can be a phone, a camera and microphone
connected to a PC or an integrated Room System
(conferencing system).

FECC

Far End Camera Control. In certain video cameras, the
accompanying software that enables a participant to
control a remote camera. Used in Continuous Presence
video conferences in conjunction with the LSD option. For
more information, see LSD.

Frame

A group of bits that make up an elementary block of video
data for transmission by certain protocols.

Frame Rate

The number of video frames displayed on-screen during
one second, measured in fps (frames per second).

G.711

ITU-T audio algorithm, 64Kbps, 3.4 kHz.

G.722

ITU-T audio algorithm, 64Kbps, 7 kHz.

G.728

ITU-T audio algorithm, 16Kbps, 3.4 kHz.

Gatekeeper

A type of server that performs two main functions:
translates LAN alias addresses of terminals and gateways
to IP addresses and provides bandwidth management.

H.221

ITU-T standard that defines how to multiplex video, audio,
control, and user data into one serial bit stream.

Abbreviation/
Term

Explanation