Polycom RealPresence 1500 Administrator's Manual page 621

4 Click the Video Services tab.
The IVR Services - Video Services tab is displayed.
5 Define the following parameters:
:
IVR Services Properties - Video Services Parameters - Invite Participants
Video Services
Dial out protocols order
DTMF forward duration
Polycom®, Inc.
Description
Select the order of the network protocols that will be used by the system to dial
the destination number. The system will start dialing using the first protocol, and
if the call is not answered it will continue with the second, third and fourth
protocols (if they are enabled) until the call is answered. By default, H.323 is set
as the first protocol and SIP as the second while the remaining protocols are
disabled (set to Off).
For PSTN calls, select the PSTN protocol and not ISDN.
Set PSTN before ISDN if both PSTN and ISDN protocols are required.
Use this field when connecting to another conferencing entity with an IVR,
requiring the input of a password, destination number or ID. Enter the number of
seconds that the system will wait for the input of additional DTMF digits such as
a password or conference number. The range can be from 10 seconds to 600
seconds. Default is 60 seconds.
IVR Services
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