RADVision MCU-323, User Manual

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MCU-323 Functionality
1-5
Audio Mixing
The MCU–323 performs audio mixing on the incoming audio streams, and distributes an
adjusted audio stream to the conference participants (removing the self– audio stream of
each participant). The audio level adjustment is performed by an AGC (Automatic Gain
Control) algorithm. The supported audio codings are: G.711 A Law and µ Law, G.723.1 and
G.729 A/B. A mix of these audio codings in the same conference is also supported.
Audio Transcoding
Audio transcoding is the conversion of one audio transmission format into another using
various algorithms to achieve different audio quality levels at reduced bandwidth levels.
This can be used to accommodate endpoints that can only process specific audio formats,
and to free up bandwidth on the LAN.
The MCU-323 provides audio transcoding for the G.723.1 (at bandwidth of 5.3 or 6.3 Kbps)
and G.729 A/B (at bandwidth of 8 Kbps) codecs. The MCU-323 can be configured to
prioritize the transcoding, giving preference to a particular codec that is requested in a
defined conference service. The transcoding capacity depends on the number of optional
transcoder modules installed in the MCU-323 and is available in configurations of 0, 16, or
24 supported ports. The MCU-323 can support conferences that combine transcoding
methods such as G.723.1 and G.711 or G.729 and G.711.