User's Manual
Polycom® RealPresence Collaboration Server (RMX) 1500/2000/4000 Administrator’s Guide
2-2 Polycom, Inc.
All endpoints that do not support the H.264 SVC protocol such as H.263, H.264, or RTV, are 
considered AVC endpoints.
The MCU process the received video, transcodes it and send the resulting video streams to 
the endpoints. The video processing that is required differs according to the video session 
set for the conference, with all the processing performed by the MCU. For more details, see , 
"AVC Conferencing - Video Session Types” on page 2-4.
Media Relay - SVC Conferencing
Media Relay SVC Conferencing is based on the SVC (Scalable Video Codec) video protocol 
and SAC audio protocol. It offers high resolution video conferencing with low end-to-end 
latency, improved Error Resiliency and higher system capacities.
The Polycom multipoint media server, serves as an integrated media relay engine that 
provides media streams for displaying conferences at low latency video experience in video 
conferences. For more details see, "SVC-based Conferencing” on page 2-13.
Mixed CP and SVC Conferencing
This type of conference enables participants with SVC-enabled endpoints and AVC 
endpoints to participate in the same conference.
Each endpoint connects according to its capabilities. The MCU processes the AVC video 
streams and converts them into SVC video Streams and relays them to the SVC participants 
that constructs the video layout on the endpoint. 
In the same way, the MCU processes the video streams received from the SVC participants, 
converts them into AVC video and then transcodes all the video streams to compose the 
video layout that is sent to the AVC endpoints.
Conferencing Capabilities in the Various Conferencing Modes
The following table summarizes the conferencing capabilities and options available in the 
different Conferencing Modes. 
Table 2-1  Conferencing Capabilities in the Different Conferencing Modes
Feature CP Only Mixed CP & SVC SVC Only
Reservations
 
Operator 
Conferences
Entry Queues
* * *
Permanent 
Conference
 
Cascading
** **
IVR
Reduced IVR set for 
SVC endpoints










