Wiring Diagram -
A-Side Pinout
Pin Color Signal
Z-Side Pinout
Pin Color Signal

Notes

Cable Reference Guide

RJ45 Ethernet Cables

T568B Straight-Through

Most common standard in North America. Connect switch to PC, router to switch. Both ends identical.

T568A Straight-Through

Government/military standard. Both ends identical. Compatible with T568B devices.

Crossover

Connect like devices: PC to PC, switch to switch. One end T568A, other T568B.

Rollover (Console)

Cisco console cable. Pin 1 connects to pin 8, pin 2 to pin 7, etc. Used with console adapter.

RS-232 Serial Cables

Null Modem

Direct connection between two DTEs (e.g., two PCs). Crosses TxD/RxD and handshaking signals.

Straight-Through

DTE to DCE connection (PC to modem). All pins connect 1:1.

Loopback

Testing adapter. Connects TxD to RxD and handshaking signals to allow self-test.

Cisco Console

RJ45 rollover cable + DB9 adapter. Standard for Cisco/Juniper device management.

Wire Color Standards

T568B (most common): White/Orange, Orange, White/Green, Blue, White/Blue, Green, White/Brown, Brown

T568A: White/Green, Green, White/Orange, Blue, White/Blue, Orange, White/Brown, Brown

Note: The key difference between T568A and T568B is that pairs 2 and 3 (orange and green) are swapped.

Common Applications