TANDBERG MCU 4500 Computer Hardware User Manual


 
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The MCU is able, if required, to allocate its available media ports in advance to specific conferences. This means that
it is able to guarantee that a certain number of participants will be able to join that conference, irrespective of how
many other people are using the MCU for other conferences at the same time.
There are three types of media ports available on the MCU, , , and
.
For information about the number and type of ports provided by each MCU model, refer to MCU port matrix.
The term video port refers to a port that can be used by a video-conferencing endpoint for a call. Thus, a video port
includes both video audio streams (bidirectionally) and so the number of video ports available represents the
number of "normal" video calls that the MCU is able to maintain simultaneously.
In general, each endpoint in a conference is able to use either a video port or an audio-only port, though normally the
MCU will assign video ports to video-capable devices and audio-only ports to audio-only devices.
If a video-capable device joins a conference which has just audio-only ports available, the MCU will assign it an audio-
only port that participant will be able to listen to other people and contribute their own audio to the conference but
the MCU will not transmit video to it (and will not use any video received from it). If an audio-only device such as a
simple telephone joins a conference which has just video ports available, the MCU will assign it a video port, which
includes audio capability. The video capability of that allocation will not be used, but the audio device will be able to
participate as normal in the conference. The exception to this is VNC - because this is a video-only protocol, the
MCU does not permit VNC connections to use audio-only ports.
Streaming a conference requires use of a or a . Where streaming and
content channel ports are provided, streaming viewers and conferences' content channel (H.239 or BFCP) video
allocations will use the streaming and content channel ports rather than the available video ports; where streaming
and content channel ports are not provided, streaming viewers and content channel allocations will use available
video ports.
If a streaming and content channel port or a video port is unavailable (or not allocated in advance when the MCU is in
Reserved mode), it will not be possible to stream that conference. If a video port has been allocated for streaming a
conference, any number of streaming viewers will be able to view that conference via streaming, at any combination
of available bit rates.
The total number of media ports available depends on the MCU model; refer to the product datasheets available on
the web site, or to MCU port matrix for more information.