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Chapter 3: ISDN Line Ordering and Configuration
In the U.S. and Canada, Network Terminator equipment (NT1) is required to provide an interface between the
In Europe and Japan, the telephone company provides the NT1 and offers
The ISDN pairs are the same wires that exist for analog telephone service. In most cases, the same wires can be used for the ISDN line. The EIA/TIA standard for wiring is Unshielded Twisted Pair (UTP) cable, Category 3 or above, 24 AWG (American Wire Gauge). The standard also recommends using
ISDN BRI Configurations
ISDN BRI lines can be configured in
Since the ISDN BRI line is used for a high speed
SPIDs, Directory Numbers and Telephone Numbers
The service provider gives you up to three sets of numbers for identifying the ISDN line and devices. You may be assigned none, one or two Service Profile Identifier numbers (SPIDs) or Directory Numbers (DNs) depending on the service provider and country.
Phone Numbers
Numbers used for others to dial into the ISDN B channels on your ISDN line (similar to analog line phone numbers).
Directory Numbers
Address assigned by the ISDN service provider for each device operating on the line. This number can be similar to the phone number. The Directory Number is not generally implemented outside the U.S.