User's Manual
Polycom, Inc. 19-1
19
Gateway Calls
The RealPresence Collaboration Server (RMX) can be used as a gateway that provides 
connectivity across different physical networks and translates multiple protocols for point-
to-point rich media communications.
The Collaboration Server supports the widest range of video and audio algorithms. It allows 
sites with different frame rates, connection speeds, audio algorithms, video resolutions and 
network protocols to transparently connect with one another. It also enables multipoint 
conference creation from an endpoint.
A special conference acting as a Gateway Session is created on the Collaboration Server. It 
includes one dial-in connection of the endpoint initiating the Gateway Session and one or 
several dial-out connections to endpoints. It provides connectivity between the various 
protocols: H.323, SIP, ISDN and PSTN. 
To enable the gateway functionality a special Gateway Profile is defined on the 
Collaboration Server.
Gateway Functionality
The following features and capabilities are supported in gateway calls:
• Gateway Sessions are in CP mode only. 
If Video Switching is selected in the Profile assigned to the Gateway Session, the system 
ignores this setting and will run the Gateway Session in CP mode.
— From Version 7.2, Gathering phase is not supported in gateway calls, even if it is 
defined in the Profile assigned to the Gateway Profile.
• H.239 Content 
• FECC - IP participants only as FECC is not supported by the ISDN protocol. 
• Recording. The Recording Link is not considered as a participant and therefore, the 
gateway session will automatically end when only one of the participants remains 
connected in addition to the recording link. The video of the Recording Link is not 
included in the display of the video of the gateway call.
• Forwarding of DTMF codes from the Gateway Session to a conference running on 
another gateway, MCU or DMA. This enables the participant to enter the required 
conference and/or chairperson password when connecting to another conference.
DTMF forwarding is enabled when there are only two participants connected to the 
Gateway Session.
• Forwarding of all DTMF codes sent by participants in the Gateway Session to all PSTN 
and ISDN participants. This is enabled by adding the 
Gateway calls are supported in AVC Conferencing Mode only.










