Polycom (RMX) 1500 User Manual

RealPresence Collaboration Server (RMX) 1500/1800/2000/4000 Administrator’s Guide 

Polycom®, Inc. 

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● MCU to MCU

In this topology, an ISDN participant from conference running on MCU A calls a conference running 

on MCU B over an ISDN link.

● Content is restricted. When another endpoint wants to send content, the first endpoint must stop 

sending content before the second endpoint can initiate or send content. 

● Endpoints that do not support H.239 can receive the Content using the Send Content to Legacy 

Endpoints option.

● When a participant joins a conference with active Content, content cannot be viewed by the new 

participant. Restart the Content.

● Cascaded MCUs/Gateways must be registered with the same Gatekeeper or neighboring 

Gatekeepers. MCUs and endpoints must also be registered with Gatekeepers.

● Gateway/MCU calls require definition of IVR Services. For more information see 

.

When H.323 participants connects to another IP participants via a Gateway to Gateway call over an ISDN 
link, the dialing string includes the following components:

[GW A prefix in GK] - The prefix with which the Collaboration Server (gateway) is registered to the 

gatekeeper. 

[GW Profile ID] - The ID of the Gateway Profile defined on Gateway A to be used for routing the call to 
the Gateway B.

[GW Profile ISDN/PSTN number] - The dial-in number assigned to the Gateway Profile defined on 
Gateway B, including the required country and area codes.

From version 7.1, the content sharing protocol is H.263 when sent over ISDN Cascading link.