MGC Manager User’s Guide - Volume I
B-3CAS Channel Associated Signalling. An interface for Audio
Only conference participants. See also T1-CAS.
CIF, 4CIF, QCIF Common Intermediate Format, an optional part of the
ITU-T's H.261 and H.263 standards. CIF specifies 288
non-interlaced luminance lines, that contain 176 pixels.
CIF can be sent at frame rates of 7.5, 10, 15, or 30 per
second. When operating with CIF, the amount of data to
transmit cannot exceed 256 K bits (where K equals
1024).The CIF video format has the capacity to transmit
video images of 352x288 pixels at 36.45 Mbps and 30
frames per second. A 4CIF format has four times the
capacity of CIF; QCIF has quarter the capacity of CIF.
Circuit Another term for span; a T1 or E1 line.
Codec Coder-decoder. A device that converts voice and video
into digital code, and vice versa. Refers to the endpoint
video camera and video board that are used for
videoconferencing.
Conference Connection between two or more endpoints exchanging
video and audio information. If only two endpoints are
involved, a conference is called point-to-point and no
MCU is required. If more than two endpoints are involved,
it is called a multipoint conference, and an MCU
(Multipoint Control Unit) is required as the management
system. See also MCU.
CSU Channel Service Unit. Customer-provided equipment that
is used as an interface between a communication network
and the data terminal.
D-Channel The channel in a span or in a group of spans, which is
used to transmit signaling information between the (public
or private) switch and the MGC-100.
Abbreviation/
Term Explanation