Polycom RealPresence 800s Administrator's Manual page 764

RealPresence Collaboration Server (RMX) 800s/Virtual Edition Administrator's Guide
The Default IP Service - Networking IP dialog box opens.
4 Make sure the IP Network Type is set to H.323 & SIP even though SIP will be the only call setup
used with Office Communications Server 2007.
5 Make sure that the correct parameters are defined for the Signaling Host IP Address and Subnet
Mask.
Make sure that the IP address of the Collaboration Server Signaling Host is the same one defined as
a trusted host in Office Communications Server 2007/Lync Server 2010.
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