User guide

ISDN Router
6
In Europe and Japan
The Telephone Company provides the NT1 and offers end-users the S/T
interface.
ISDN Wires
The ISDN wires are the same wires that exist for analog telephone service in
most cases.
EIA/TIA standard for wiring:
• Unshielded twisted pair (UTP) cable, category 3 or above, 24 gauge
• 8-position RJ45 jacks for new ISDN service installation are
recommended
Configurations
ISDN BRI lines can be configured in point-to-point and multi-point
configurations and can support dual-POTS interfaces.
Point-to-point:
Only one device is connected to the ISDN line.
Multi-point:
This configuration can have up to 8 devices (ISDN telephones, ISDN
terminal adapters, ISDN routers, etc.) dropped on the ISDN line.
POTS interface device support:
Up to four devices per port but only one call initiated at a time (though
another call can be in progress).
Since the ISDN BRI line will be used for a high-speed LAN-to-LAN link, you
need to be sure that additional devices dropped on the S/T interface of the
router allow sufficient access for the router’s bandwidth requirements.