Intel ER8100STUS - Express 8100 Router, Reference Manual

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Reference.bok : Chapter04 27 Wed Apr 22 10:58:08 1998
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ISDN Numbering and Addressing
ISDN Services
MSN (Multiple Subscriber Number)
Different Directory
Number (DN) for each
terminal
Each line is allocated a block of DNs, typically 10, and when there is an incoming
call, the called number is presented to all the terminals on a passive bus.
Each terminal is programmed to respond to a different DN and thus the correct
terminal is able to answer the call.
More than one call at
same time If the attached device is capable of handling more than one call at the same time,
for example an Intel Express 8100 Router with multiple ISDN links, then it can
be programmed to respond to more than one number.
Calling Line Identification
The Calling Line Identification supplementary service is a country-dependent
default service for EuroISDN. A
Calling
terminal can present its DN to the net-
work when setting up a call. This is checked by the network and, if valid, passed
on to the
Called
party.
SUB (Sub-addressing)
One or more identifiers
for each terminal
This is the most flexible form of terminal identification. Each terminal on a line
is given one or more identifiers, each of which is a unique string of characters of
your choice.
Each of the terminals on a passive bus has its own sub-address, and all of the ter-
minals share the same ISDN number. An Intel Express 8100 Router with multi-
ple ISDN links must have a separate sub-address for each ISDN link.
String supplied by caller
In order to specify a particular terminal or an ISDN link in the Intel Express 8100
Router, the caller supplies the appropriate character string to the network when
the call is made.
The network passes this string unchanged (subject to any restrictions on length
and character set) to the called line.
DDI (Direct Dialing In)
ISPBX extension
numbers
This is a facility whereby the last few (typically 3) digits of the Directory Number
(DN) are used to specify which extension of an ISPBX is being called.
The BRA/PRA (or group of BRA/PRAs) to which the ISPBX is connected is al-
located a block of numbers.
When there is an incoming call, the last few digits of the number are presented to
the ISPBX to allow it to select the correct extension.