Specifications

Hardware Reference 31
C613-03023-00 REV P
ISDN Interface Cables
The AT-AR021(S) BRI-S/T and AT-AR021(U) BRI-U PICs provide Basic Rate
ISDN interfaces, while the AT-AR020 PRI E1/T1 provides a Primary Rate ISDN
interface.
ISDN Basic Rate
Cable
Figure 18 shows how to wire a cable to connect a Basic Rate Interface (BRI) to
the ISDN network terminating equipment (NT).
Figure 18: Pin wiring diagram for an ISDN Basic Rate straight-through interface cable
ISDN Primary Rate
Cable
Figure 19 shows how to wire a cable to connect to the RJ-45 connector of a
Primary Rate Interface (PRI). Currently there is no accepted standard for the
connector at the network termination end, so only the switch end of the cable is
shown. Consult you ISDN service provider for more information.
Figure 19: Pin wiring diagram for an ISDN Primary Rate interface (120Ω ) cable
Not connected
Not connected
TX+
TX-
RX-
RX+
Not connected
Not connected
RJ45
(to switch or router)
RJ45
(to NT)
1
2
3
6
4
5
7
8
→
→
←
←
Not connected
Not connected
RX+
RX-
TX-
TX+
Not connected
Not connected
Notes:
(1) → Output from switch or router; ← Input to switch or router.
(2) Use twisted pair cable, with pairs 3 and 6, and 4 and 5.
(3) Each wire is connected to the same pins at each end.
(4) Cable version 1.0.
1
2
3
6
4
5
7
8
→
→
←
←
BRI1NT
RJ45
(to switch or
router)
←
←
→
Notes:
(1) → Output from switch or router; ← Input to switch or router.
(2) Use Grade 5 twisted pair cable, with pairs 1 and 2, and 4 and 5.
(3) Cable version 1.0.
1
2
3
4
5
6
7
8
RX+
RX-
Not connected
→ TX+
TX-
Not connected
Not connected
Not connected
PRI120NT