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1 Introduction to the AVM ISDN-Controller T1/T1-B
1 Introduction to the AVM ISDN-
Controller T1/T1-B
1.1 The ISDN Network
ISDN, the Integrated Services Digital Network, has
been available in Germany since 1989, and is consid-
ered the universal telecommunications network of the
future.
Among ISDN’s characteristics are:
- High speed
The B channels, which are used to transmit user data,
have a throughput of 64 Kbit/s. The two B channels of
an ISDN basic-rate (S
0
) interface can be bundled to
obtain a maximum throughput of 128 Kbit/s. The
primary rate (S
2M
) interface, with 30 B channels, allows
a total throughput of about 2 Mbit/s.
- Digital transmission
In contrast to analog data communications, line inter-
ference and data errors are practically eliminated. This
makes data communications in ISDN not only faster,
but also more reliable than in analog networks.
- Fast dial-up connections
Call setup in ISDN takes only 1 to 2 seconds.
- Integration of services
Integrated services means that voice, data and images
can all be transmitted over a single network. Users only
need one line for all kinds of communications applica-
tions.