VTEL HS 2000, Руководство системного администратора

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HS 2000 System Administrator’s Handbook Glossary
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ISDN. Integrated Services Digital Network. An international standard
for transmitting voice, data, and video over digital lines at 64 Kbps.
ISDN uses two B channels to carry voice and data and a third D channel
for control signals.
BRI. Basic Rate Service. Provides two B channels and one
D channel. In North America, Primary Rate Service (PRI) provides
23 B channels and one D channel. In Europe, PRI provides 30 B channels
and one D channel.
ITU-T. International Telecommunication Union Telecommunication
Standardization Sector (formerly the CCITT). An international
organization that sets communication standards.
JPEG. Joint Photographic Experts Group. Worldwide standard for image
compression.
kilobits per second. Measure of rate of digital transmission, often
abbreviated Kbps.
MediaConferencing. A conference in which information (including
video, audio, document, and computer data) can be exchanged.
multiplexer. Electronic equipment that allows two or more signals to be
transmitted over one communications circuit.
MCU. Multiway Control Unit. Device that allows more than two sites to
be connected in a videoconference. Also called a digital switch or video
bridge.
NT-1. Converts BRI from 2-wire public network format to the 4-wire
consumer equipment. Conditions and monitors the line. May be a
component of an inverse multiplexer.
NTSC. North American standard for analog video format.
PAL. European standard for analog video format.
Pixel. Picture element. A measure of resolution for video format.