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 Pin1 | NT3 | Polarity |
| TE2 | ||
3 | Transmit | Receive | + |
| |||
4 | Receive | Transmit | + |
| |||
5 | Receive | Transmit | − |
| |||
6 | Transmit | Receive | − |
|
1Pins 1, 2, 7, and 8 are not used.
2TE 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.
3NT 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 |
|
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Cisco − WIC−1B−S/T and WIC−1B−U WAN Interface Cards Cable Specifications