Sharing Content During Conferences
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For example, in a cascaded environment, the conference rate must be identical for all links. Yet, capabilities
may vary widely between the cascading conferences (such as one conference supporting 2 Mbps, while the
other - 512kbps).
The rates listed by the MCU are up to 66% of the conference maximum line rate.
Customized Content rate list comprised of a single value of 0, means the conference bit rate capability is
too low to share content.
Selecting a line rate too low for the selected Customized Content Rate, results in an error message display.
MCU Usage Modes of Content Protocols
Depending on the endpoints capabilities, you can determine the content sharing experience by selecting the
appropriate protocol and system behavior from the Content Protocol list:
●H.263 - AVC Only
●H.263 & H.264 Auto Selection - AVC Only
●H.264 Cascade and SVC Optimized - All conferencing modes
●H.264 HD - AVC Only
Endpoints without the content capabilities matching the conference content sharing requirements, can
connect to the conference but cannot share or view content in the content channel. Depending on Legacy
definitions, they can view content in the people video layout (see Sending Content to Legacy Endpoints (CP
Only)).

H.263 (AVC CP Conferences)

In this mode, all endpoints share content using H.263 protocol. Select this option when either most
endpoints support H.2634, or to share content over a cascading conference, in which case, the cascading
link should be created prior to participants joining the conference.
For single MCU scenario, the Highest Common principle (see Highest Common) is applied to determine
content parameters. In cascading environments, a fixed rate is used (see Fixed Rate).

H.263 & H.264 Auto Selection (AVC Conferences)

Select this option to share content using a mix of H.263 and H.264 capable endpoints. Until version 7.6
(including), this option is named Up to H.264.
For single MCU scenario, the Highest Common principle (see Highest Common) is applied to determine
content parameters. In cascading environments, an H.263 fixed rate is used (see Fixed Rate) regardless of
endpoint capabilities.

H.264 Cascade and SVC Optimized

This content sharing option applies for H.264 content media protocol, and provides fixed content rate (see
Fixed Rate) and resolution according to the conference line rate. It must be used for Cascading or
SVC-enabled conferences.
The H.264 Cascade and SVC Optimized option maintains content quality, and prevents content refreshes
upon participants connect/disconnect from the conference.
In cascading environments using this option, the cascade link signaling must be H.323.