System interfaces
39
System functions and features as of R3.0
syd-0367/1.3 – R3.0 – 03.2013
2. 2
Terminal interfaces
The communication server supports digital and analogue user-network interfaces.
2. 2. 1
Digital user-network interfaces
On each of these digital user-network interfaces several appropriate terminals can
be hooked up and operated simultaneously.
2. 2. 1. 1
Terminal interface BRI-S
The S user-network interface is a digital 4-wire interface used for connecting ISDN
terminals, Terminal Adapters and ISDN PC cards. Each of these interfaces has two
64 kbit/s user information channels and one 16 kbit/s control and signalling chan-
nel (2B+D). This makes it possible to establish two independent call or data con-
nections simultaneously.
Fig. 13
Terminal interface BRI-S
Up to 8 terminals can be operated on an S user-network interface. They are ad-
dressed with the single-digit terminal selection digit (TSD).
Different modes are available for operating the BRI-S interface (
S bus protocol
set-
ting in the interface configuration):
• The
ETSI
mode is used to operate ISDN terminals, Terminal Adapters and ISDN PC
cards.
• With the
EXTERN S
mode an BRI-S interface can be used as a basic access for pri-
vate networking with QSIG / PSS1 or DSS1. It is then no longer available as a
user-network interface (see
"BRI-S basic rate interface external", page 22
).
