Multi-Tech MultiModem ISDN MT128ISA-UV, User Manual

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MultiModemISDN User Guide
MT128ISA/PCI
Introduction
This chapter describes how to make all the physical and software driver connections
necessary for your terminal adapter to operate in an ISDN environment. Please check the
package contents list in Chapter 1 before beginning your installation.
ISDN BRI Line
Before running the ISDN adapter, you need to get an ISDN BRI (Basic Rate Interface) line
from your local telephone company. Your ISDN service provider will provide information to
you about the ISDN central switch type, pertinent subscriber information and SPID (Service
Profile ID) number(s).
SPID (Service Profile ID)
The Service Profile ID (SPID) is applicable in the U.S. only. SPIDs are a series of numbers
that inform the central office switch which services and features to provide to an ISDN
device. The generic SPID format comprises 14 digits. The first 10 digits are the main
telephone number on the terminal. The last 4 digits are dependent on the number of
terminals on the interface and the services they support.
NT1 Connection
An ISDN Basic Rate (BRI) U-Loop consists of 2 conductors from the CO (telephone
company central office) to the customer premises. The equipment on both sides of the U-
loop has been designed to deal with the long length of the U-loop and the noisy environment
it operates in. At the customer premises the U-loop is terminated by an NT1 (network
termination 1) device. An NT1 is a device which provides an interface between the two-wire
twisted-pairs used by telephone companies in their ISDN BRI network and an end-user's four
wire terminal equipment. The NT1 drives an S/T-bus which is usually made up of 4 wires, but
in some cases may be 6 or 8 wires.
The name of the S/T bus comes from the letters used in the ISDN specifications to refer to
two reference points, S and T. Point T refers to the connection between the NT1 device and
customer supplied equipment. Terminals can connect directly to NT1 at point T, or there
may be a PBX (private branch exchange, i.e. a customer-owned telephone exchange).
When a PBX is present, point S refers to the connection between the PBX and the terminal.
Note that in ISDN terminology, "terminal" can mean any sort of end-user ISDN devices, such
as data terminals, telephones, FAX machines, etc. The diagram which follows reflects
interface points in a typical ISDN network.
If your ISDN product operates with a S/T outlet interface, you need an NT1 device to connect
to the ISDN switch. MT128PCI-SD/SV adapters need an NT1 device to connect to the ISDN
switch, but the MT128ISA-UV adapter does not require NT1 device. In the UK, and in many
European countries, an NT1 device is supplied by your telephone company.