10.20.1. Functional Bus 
You can connect terminals to the functional bus with the SBDSS1 or
NIBRI protocol. You can only connect non-voice dial-in devices. You can
only configure one call number per bus and one terminal per service (see
also the following Note on MSN call numbers).
Figure 99. Functional bus (configuration example)
IMPORTANT:
The introduction of MSN call numbers lets you
reach functional terminals at the main number or at a new call number.
You can also connect additional functional terminals for the same services
as already configured at the main number to the bus and reach them at
a new call number (see also "EURO ISDN Terminals", Section
120.2.1, "Multiple Subscriber Numbers (MSN) on the S0 Bus".
Configure the terminals for this example as follows:
ADD-SBCSU:STNO=number,OPT=FBUS,CONN=DIR, DVCFIG=SET600&FAX&DTE,COS1=number,COS2=number, LCOSV1=number,LCOSV2=number,LCOSD1=number, LCOSD2=number,SPROT=SBDSS1,FPROT=SBDSS1,DPROT=SBDSS1;