Polycom RMX 1500 Administrator's Manual page 59

The participants Video Protocol in the New Participant or Participant Properties - Advanced tab
should be left at (or set to) its default value: Auto.
The Auto setting allows the video protocol to be negotiated according to the endpoint's
capabilities:
•
•
Protocol Forcing
Selecting H.264, RTV, H.263 or H.261 as the Video Protocol results in endpoints that do not
support the selected Video Protocol connecting as Secondary (audio only).
Polycom, Inc.
OCS endpoints and Lync Server clients connect to the conference using the RTV
protocol.
Other endpoints negotiate the video protocol in the following sequence: H.264,
followed by RTV, followed by H.263 and finally H.261.
Chapter 2-Additional Conferencing Information
Auto
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