Nortel Compact Ics 6.0 Installer Guide

P0992669 03Compact ICS 6.0 Installer Guide
Welcome to ISDN
This chapter provides you with some background information about ISDN 
and also includes information about:
Analog vs. ISDN
Type of ISDN service
ISDN layers
ISDN Bearer capability
Services and features for ISDN BRI
ISDN hardware
ISDN standards compatibility
Integrated Services Digital Network (ISDN) technology provides a fast, 
accurate and reliable means of sending and receiving voice, data, images, 
text, and other information through...

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An analog modem operating at 14.4 K takes about 4.5 minutes to transfer 
a 1 MB data file and a 28.8 K modem takes about half that time. Using one 
channel of an ISDN line, the transfer time is reduced to only one minute. If  
two ISDN channels are used, transfer time is just 30 seconds.
When transmitting data, the connect time for an average ISDN call is about 
three seconds per call, compared to about 21 seconds for the average 
analog...

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ISDN layers
ISDN layers refer to the standards established to guide the manufacturers 
of ISDN equipment. The layers include both physical connections, such as 
wiring and logical connections, which are programmed in computer 
software. 
When equipment is designed to the ISDN standard for one of the layers, it 
works with equipment for the layers above and below it. 
There are three layers at work in ISDN for Norstar. To support ISDN...

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Services and features for ISDN BRI
As part of an ISDN digital network, your Compact ICS supports enhanced 
capabilities and features, including:
faster call set up and tear down
high quality voice transmission
dial-up Internet and local area network (LAN) access
video transmission
network name display
name and number blocking (BRI and analog)
access to public protocols (NI-1 for BRI)
BRI services and features
data transmission at...

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subaddressing of terminal equipment (TE) on the same BRI loop. 
However, terminal equipment which supports sub-addressing is not 
commonly available in North America.
Transmission of B-channel packet data is not supported by Compac tICS.
Contact your ISDN service provider for more information about these 
services and features. Packages for ISDN service in North America are 
described on page 32.
The terminal equipment (TE) connected to the...

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Network Call Diversion (ETSI system feature)
This feature is a network function of ETSI E1 lines that allows forwarding 
and redirection of calls outside the Norstar network when using an ETSI 
ISDN line. Functionality is similar to that of External Call Forward (ECF). 
NCD redirects calls using the same line on which they arrive. Call forward 
is efficient since there is no need for additional outside lines.
ISDN hardware
To support...

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U-LT reference point
The U-LT reference point connection provides a point-to-point digital 
connection between Norstar and TE equipped with a U interface.
A U-LT loop supports up to eight ISDN DNs, which identify TE to the ICS.
U-NT reference points
The U-NT reference point connection provides a point-to-point digital 
connection between the ISDN network and the ICS.
A U-NT loop provides lines that can be used by all Norstar telephones,...

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To deliver D-packet service, a network connection (U-NT) is programmed 
to work with a terminal connection (U-LT). The loops must be on the same 
physical card. For example, if the network connection is a loop found on 
the BRI Card in Slot 1, the terminal connection must be a loop found on the 
same card.
S reference point
The S reference point connection provides a point-to-point digital 
connection between Norstar and ISDN terminal...

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T reference points
The T reference point connections provide a point-to-point digital 
connection between the ISDN network and Norstar.
A T loop provides lines that can be shared by all Norstar telephones, 
peripherals and applications, and ISDN TE.
An T loop can be used in combination with an S loop to provide D-packet 
service for a point-of-sale terminal adapter (POSTA) or other D-packet 
device. D-packet service is a 16 kbps data...

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Systems synchronize clocking to the first available, functional, network 
connection. If there are excessive errors on the reference network 
connection, or the loop fails, the next available, functional, network 
connection is used for clock synchronization. 
When you configure the network connections to the Compact ICS, you 
should take into account the system preferences for selecting loops for 
synchronization:
lower numbered loops have...