Intel ER8100STUS - Express 8100 Router, Reference Manual

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Reference.bok : Chapter04 28 Wed Apr 22 10:58:08 1998
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Permanent ISDN
ISDN Services
Example
A customer could be allocated all numbers in the range 678000 to 678999.
A call to any of these numbers would be routed to the same BRA/PRA, the ISP-
BX being responsible for directing the call to the appropriate extension, these be-
ing numbered from 8000 to 8999.
Calling Line Identification
The Calling Line Identification supplementary service is a default service for Eu-
roISDN. For outgoing calls, the ISPBX can provide the DDI number of the orig-
inating extension for presentation to the called subscriber.
Permanent ISDN
Permanent ISDN
connections
In some countries, Permanent links are available over ISDNs which offer a static
association between two sites without the need for the signalling associated with
normal ISDN links. Permanent link are allocated by the ISDN provider and are
similar to leased line WAN links as they are always available for data transfers.
Signalling
No signalling or dialing is required for Permanent ISDN connections. Permanent
ISDN links operate on Layer-1 only—Layer-2 and Layer-3 are not used by Per-
manent ISDN.
Permanent ISDN link
types available in the
router
The Permanent ISDN link types available in the Intel Express 8100 Routers with
a Basic Rate Interface (BRI) are:
■
Permanent 64 kbps or 56 kbps
which offers two 64 kbps or 56 kbps Permanent ISDN links which can be to
different sites.
■
Permanent 128 kbps or 112 kbps
which offers a single 128 kbps or 112 kbps link to another site.
Permanent ISDN connections using the D-channel are not supported.
These modes of operation for the ISDN Basic Rate Interface are selected on the
Advanced screen for the ISDN port.
ISDN Standards
A common standard
It should be possible to buy a piece of equipment anywhere in the world, plug it
in anywhere in the world and communicate with anywhere in the world. This is
the main goal of ISDN. However, at the present time, a world-wide ISDN stan-
dard does not exist. Each country has its own version of an ISDN standard.
Progress is however being made, especially in Europe.