Polycom MGC Administrator Administrator's Manual page 83

For the system to recognize the PRI line that connects to the Net-T1/Net-
E1 Network Interface card you have to assign the PRI line's circuit ID as
defined in the ISDN Network Services to the Net-T1/Net-E1 Network
Interface module.
6. Fill in the Span A section as follows:
a. Clear the Null Configuration check box to indicate that a PRI line
is connected to the Network Interface Module.
b. In the Circuit ID box, enter the circuit ID as defined in the Network
Service-Span and Phones dialog box. According to the selected
Circuit ID, an ISDN Network service is assigned to the network
card. Each span can be assigned a different ISDN Network Service.
c. Click Apply.
The name of the network service appears in the Service Name box.
7. Click OK.
To configure the Net-T1/Net-E1 ISDN network span as primary or
backup clock:
1. In the Browser pane, click the slot containing the ISDN Network
Interface module (PRI) to configure in the Status pane, or click the plus
[+] icon next to the Card icon to expand its units tree.
If you clicked the slot, the module's units and configuration are
displayed in the Status pane. If you expanded the units tree, the units are
displayed in the Browser pane.
MGC Administrator's Guide
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