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Conferencing Modes Overview
The MCU system offers the following types of conferences (Conferencing Modes), based on the video
protocol and the video display during the conference:
AVC-based Conferencing - CP Only (Video Transcoding)
SVC-based Conferencing (Media Relay) - SVC Only
Mixed AVC and SVC Conferencing - CP and SVC

AVC Conferencing

AVC-based Conferences allow endpoints that support AVC video to connect to these conferences. AVC
(Advanced Video Coding) video refers to the H.264 video protocols used to send and receive video. On the
Collaboration Server system it also includes all the standard video protocols such as H.261, H.263, and
RTV.
All endpoints (including SVC-enabled endpoints) have AVC capabilities and can connect to AVC
conferences running on the MCU. AVC-based endpoints can connect using different signaling protocols and
different video protocols.
Based on the video processing required during the conference, the Collaboration Server offers the
Continuous Presence Conferencing Mode for AVC-based conferencing.
The Conferencing Mode determines the video display options (full screen or split screen with all participants
viewed simultaneously) and the method in which the video is processed by the MCU (with or without using
the MCU’s video resources).

Continuous Presence (CP) Conferencing

The dynamic Continuous Presence (CP) capability of the Collaboration Server system enables viewing
flexibility by offering multiple viewing options and window layouts for video conferencing. It enables several
participants to be viewed simultaneously and each connected endpoint uses its highest video, audio and
data capabilities up to the maximum line rate set for the conference.
AVC-based endpoints can connect to the conference using any:
Signaling protocol: H.323, SIP, (and RTV line rate, up to a maximum line rate defined for the
conference
Video Protocol: H.261, H.263, H.264 Base Profile and H.264 High Profile) and at any resolution and
frame rate, provided they meet the minimum requirements set for the conference:
Video Resolutions: from QCIF, CIF and up to 1080p30
Frame rates up to 30fps
In Continuous Presence conferences, the MCU receives the video stream from each endpoint at the video
rate, video resolution and frame rate that it is capable of sending, and it superimposes all the received
streams into one video stream that includes the input from the other endpoints arranges in the selected
video layout.