Conferencing Modes Overview
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layout to the participant. In the displayed example, the Collaboration Server creates different video layouts
for each AVC endpoint.
MCU Resource Capacities for Mixed CP and SVC Conferences
In a mixed CP and SVC conference, video resources are allocated according to the MCU type and the
translation pools (AVC to SVC and SVC to AVC) used to convert video streams. Translation pools are
dynamically allocated, when the conference becomes a mixed CP and SVC conference; resources are not
released when the conference stops being a mixed CP and SVC conference. The translation pools send
one SVC to AVC stream with a resolution of 360p, two AVC to SVC streams with a resolution of 360p and
180p for AVC HD endpoints, and one video stream with a resolution of 180p for AVC SD endpoints. When
a video stream with a resolution of 360p is not available, a video stream with a resolution of 180p is sent
instead.
Translations between different endpoints can be done without using the highest resolution, thus saving
translation resources. CP video layouts in mixed CP and SVC conferences support the standard resolutions
as in normal CP conferences.
Taking these factors into consideration and the type of MCU deployed in the environment, the resource
capacities for a mixed CP and SVC conference can vary.
The following table describes an example of the resource capacity allocations for the RealPresence
Collaboration Server:
The first four resource types in the resource capacity allocations table are endpoints in a CP only conference
or a mixed CP and SVC conference before the actual resource allocations occur.
In a mixed CP and SVC conference, video resources are used according to the amount of both AVC and
SVC participants in the conference and according to the actual type of the conference - mixed CP and SVC
conferences or CP only conferences. The ratio of resources in a mixed conference is one AVC HD (720p30)
video resource to three SVC video resources, meaning for each AVC HD video resource, three SVC video
resources can be allocated.
In this resource capacity allocations example, the mixed CP and SVC conference can allocate a
combination of AVC and SVC ports depending on the endpoints that are defined in the actual conference.
For example, a conference can be defined as a mixed CP and SVC conference but will only allocate
resources as a mixed conference when both AVC and SVC endpoints join the conference. When there are
only one resource type of endpoints participating in the conference, such as AVC or SVC, the resource
allocations are assigned according to the type of endpoint. For instance, a mixed CP and SVC conference
Resource Capacity Allocations
Resource Type Number of Available Ports
Mixed CP and SVC (HD) (Example) 20 AVC
90 SVC
HD720p30 40
SD (@ 30 fps) 40
SVC Only 60
CIF (@ 30 fps) 60