The Integrated Services Digital Network (ISDN) Basic Rate Interface (BRI) WAN interface cards are shared
between the Cisco 1600, 1720, 2600 and 3600 Series Routers. Each card supports a single ISDN BRI port
offered with and without the NT1 interface.
The S/T WAN interface card module (WIC−1B−S/T) needs the external Network Termination 1 (NT1) device
whereas the U WAN interface card module (WIC−1B−U) has an internal NT1 device.
Cables
The WIC−1B−S/T interface card requires RJ−45 to RJ−45 straight−through cables (provided by the
customer).
ISDN BRI S/T Port Pinouts
The table below shows the ISDN BRI S/T port pinouts (RJ−45).
8 Pin
1
TE
2
NT
3
Polarity
3
Transmit
Receive
+
4
Receive
Transmit
+
5
Receive
Transmit
−
6
Transmit
Receive
−
1
Pins 1, 2, 7, and 8 are not used.
2
TE refers to terminal terminating Layer 1 aspects of TE1, TA, and NT functional groups. This applies to the
Cisco 1603 and the ISDN BRI S/T WAN interface card.
3
NT refers to network terminating Layer 1 aspects of NT1 and NT2 functional groups. This applies to the
Cisco 1604 ISDN S/T port.
BRI S/T WAN Interface Card LEDs
The table below lists the BRI S/T WAN interface card LEDs and their meaning.
LED
Meaning
B1
Active connection on B1 channel
B2
Active connection on B2 channel
OK
ISDN port has established a connection with the central
office switch
Cisco − WIC−1B−S/T and WIC−1B−U WAN Interface Cards Cable Specifications
