VTEL WG500, Installation Manual

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A.1
WG500
TM
Appendix A
ISDN Requirements
This appendix will explain the ISDN requirements for the WG500-384i. It will also
guide you in asking the correct questions of your telecommunications provider so that
you can obtain the network information you will need for installation.
Information about your ISDN line
Before you install WG500, be sure that the available ISDN line provides an S/ T
interface for WG500 (this may require an NT1 device). If you are unsure, contact your
telecommunications provider.
NT1
An NT1 (Network Terminating) device is required if the telephone company has
supplied a U-interface. The interface on the board is a S/T interface. This requirement is
based on each country. For example, in Europe the telephone company owns the NT1
device and therefore supplies it at point of termination. In the United States the NT1
device is customer-owned, so therefore the telephone company will provide a
U-interface at point of termination. In the case of the US, the customer is required to
supply an NT1 device. To determine your requirement, contact your
telecommunications provider or your network manager.
What you need to know
You also need to know the following ISDN information from your telecommunications
provider:
•
the ISDN central office switch type
•
whether or not the type of switch you use requires SPID (Service Profile
IDentifier) numbers or DNs (Directory Numbers), and if so, what those
numbers are
•
the telephone numbers people will dial to place a call to your WG500.
The telephone company assigns a telephone number to each ISDN line. (Each ISDN BRI
connection has two B channels, or lines.) This means that WG500-384i users may have
six telephone numbers. The two numbers for each BRI may be the same, or each BRI
may have a different number.