Sharing Content During Conferences
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During content sharing, the MCU does not permit endpoints to increase their content bit rate, only their
content resolution.
For more information, see H.263 Content Rate Table and H.264 Highest Common Content Rates Table. For
information on minimum content rates as determined by system flags, see H.264 HD System Flags.

Fixed Rate

In this method the content rate is fixed, and endpoints not supporting this rate do not receive content over
the content channel. Endpoints whose capabilities are too low, can only view content over the people video
layout (see Sending Content to Legacy Endpoints (CP Only)).
For SVC-enabled conferences, the MCU uses H.264, and 128 Kbps as the fixed content rate.
For H.263 cascaded conferences, the MCU automatically uses a fixed rate (once a cascaded link is
detected) according to the content rates described in Highest Common and Fixed Content Bit Rate
Allocation for H.263.
For H.264 cascaded conferences, the MCU uses a fixed rate according to the content rates described in
H.264 Cascade and SVC Optimized (Fixed) Content Rates Table.
Multiple Content Resolutions
In this method, the content is shared in multiple streams, one for each video protocol: H.263 (optional) and
H.264HD (mandatory). Separate video resources are used for processing the content for each of the
required content streams. The MCU then applies the Highest-Common principle for sharing content with
each group of endpoints. In cascading conferences, an additional resource is dedicated for the cascading
link(s), with a fixed (H.264 Cascade and SVC Optimized) rate shared over the cascaded link(s).
This allows endpoints with different capabilities to connect/disconnect without having to repeatedly restart
content sharing process.
Endpoints not supporting the content capabilities set for the conference, receive the content over the people
video layout (see Sending Content to Legacy Endpoints (CP Only)).

Guidelines for Sharing Contents using Multiple Content Resolutions

Multiple Content Resolutions is supported only in CP conferences.
Content is always provided to H.264 HD endpoints.
This method must be used for cascaded and SVC-enabled conferences.
This option is available only in AVC CP conferencing mode.
Multiple Content Resolutions option is not supported in Ultra Secure Mode.