Polycom RMX 1500 Administrator's Manual page 217

Chapter 3-Cascading Conferences
Defining the Cascade Enabled Entry Queue on the RMX
If the dialing is done from the conference running on the MGC that is the
Master MCU, a Cascade-enabled Entry Queue must be defined on the
RMX setting it as Slave.
For more details, see RMX to RMX Cascading.
Defining the Cascading Conferences
The table below lists the line rates and the video settings that should be
used when defining the conferences on the MGC. The same line rates
should be selected when defining the Conference Profiles on the RMX, as
well as whether the conference is HD Video Switching. However, the
video settings will be automatically selected by the system.
Table 3-8 Recommended Conference Line Rates for Cascaded Conferences
Conference Line
Topology Video Session Mode
Rate
MGC - CIF 263
768Kb/s, 2Mb/s
MGC
RMX - CIF 264 CP

MGC - HD VSW
RMX
1.5Mb/s
RMX - HD VSW
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