User's Manual
RealPresence Collaboration Server (RMX) 1500/2000/4000 Administrator’s Guide
19-8 Polycom, Inc.
Enabling or Disabling Direct IP Dialing
The direct IP dialing is enabled by default. To disable it, manually add the flags 
GK_MANDATORY_FOR_CALLS_OUT and GK_MANDATORY_FOR_CALLS_IN to 
the System Configuration - MCMS_PARAMETERS dialog box and for each flag enter the 
required value (YES or NO).
For more information on flag definition, 
see "Modifying System Flags” on page 22-1.
ISDN Participants
Two dialing methods are available to ISDN/PSTN participants:
•Via Gateway IVR
• Direct with automatically generated destination dial strings from dial-in strings. This 
dialing method is available from Version 7.1 and is supported on Collaboration Server 
with MPM+ and MPMx cards.
In addition, PSTN participants can dial the Gateway IVR and can use the MCU or DMA 
prefix in the gatekeeper together with the conference ID/endpoint alias as the destination 
string to simplify the input. This is one of the methods for PSTN participants to connect to a 
virtual Meeting Room on the DMA. 
Gateway IVR 
In this flow, the calling endpoint enters the dialing string that includes the access number to 
the Collaboration Server Gateway Profile. 
The endpoint connects to the Collaboration Server and is welcomed by the IVR Welcome 
slide and message: “Please enter the destination number” followed by the dial tone.
Using the endpoint’s DTMF input device such as remote control, the participant enters the 
number of the destination endpoint followed by the # key. Only one number can be dialed.
While the system dials to the destination endpoints, the participant hears the dialing rings. 
During the connection phase, the number being dialed is displayed on the screen of the 
calling endpoint. 
If the call is not answered or it cannot be completed using one communication protocol, the 
system will try to connect the endpoint using the next communication protocol according to 
the selected protocols in the following order: H.323, SIP and ISDN. 
PSTN numbers are identified separately and are dialed immediately without trying other 
connections.
YES YES Dial-in call is connected using the Gatekeeper.
Table 19-2  GK_MANDATORY_FOR_CALLS_IN - System Flag (Continued)
Flag Value
Gatekeeper 
Available
Results
For flag changes (including deletion) to take effect, reset the Collaboration Server. For more 
information see "Resetting the Collaboration Server (RMX)” on page 21-77.










