Cisco Catalyst 2000 - T1 E1 CSUDSU Connections

Appendix A: Cabling Quick Reference 269
T1/E1 CSU/DSU Connections
You can also make back-to-back connections between two routers with integrated T1/E1
CSU/DSUs using a specially made cable. Again, the transmit and receive pairs are crossed
in the cable. Table A-5 lists the pinout connections of both RJ-48 (an RJ-45 will do) ends
of the cable.
Table A-5 RJ-48 Connector Pinouts for Back-to-Back T1/E1 CSU/DSU Connections
RJ-48 Pin
End A
Description
End A
Description
End B
RJ-48 Pin
End B
1 RX (input) TX (input) 4
2 RX (input) TX (input) 5
3––3
4 TX (output) RX (output) 1
5 TX (output) RX (output) 2
6––6
7––7
8–– 8