Polycom QDX 6000 System Administrator's Manual page 27

You can configure the Polycom QDX 6000 system so that users can choose to
place IP-to-ISDN calls through a gateway.
To allow users to place an IP-to-ISDN call through a gateway:
1. Make sure the system is registered with a gatekeeper.
2. Go to System > Admin Settings > Network > Call Preference and enable
ISDN Gateway.
3. If you want to allow users to place IP-to-ISDN calls through a gateway
when calling from the directory, do one of the following:
— On the Network Dialing screen, set Preferred Dialing Method to
Auto and select ISDN Gateway as the first choice under Video
Dialing Order. With this configuration, IP-to-ISDN calls placed from
the directory will be placed through a gateway if an ISDN number and
IP extension exist. IP-to-IP calls placed from the directory will be
placed through a gateway if an IP address and IP extension exist.
— On the Network Dialing screen, set Preferred Dialing Method to
Manual. With this configuration, users can select ISDN Gateway
from the list of call types that appears when placing a call from the
directory.
Networks
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