The Wiert Corner – irregular stream of stuff

As I always forget the images on UTP wireing in both connectors and outlets and forget which standard is T568A and T568B: T568A and T568B termination – TIA/EIA-568 – Wikipedia:

Pin	T568A Pair	T568B Pair	10BASE-T 100BASE-TX	1000BASE-T Signal ID	Wire	T568A Color	T568B Color	Pins on plug face (socket is reversed)
1	3	2	TX+	DA+	tip	white/green stripe	white/orange stripe
2	3	2	TX-	DA-	ring	green solid	orange solid
3	2	3	RX+	DB+	tip	white/orange stripe	white/green stripe
4	1	1	–	DC+	ring	blue solid	blue solid
5	1	1	–	DC-	tip	white/blue stripe	white/blue stripe
6	2	3	RX-	DB-	ring	orange solid	green solid
7	4	4	–	DD+	tip	white/brown stripe	white/brown stripe
8	4	4	–	DD-	ring	brown solid	brown solid

Note that the only difference between T568A and T568B is that pairs 2 and 3 (orange and green) are swapped.

For cross-over cables (used less and less because of Auto MDI-X which is standard in 10000BASE-T) this is slightly different Appendix B: Ethernet Crossover Cables – Configuring and Troubleshooting Ethernet 10/100/1000Mb Half/Full Duplex Auto-Negotiation – Cisco [WayBack]:

Four Twisted-Pair Crossover Cable Schematics for 10/100/1000 and 1000BASE-T GBIC Module Ports

There are some nice colour coded wiring diagrams at Tech Stuff – LAN Wiring and Pinouts [WayBack] for both straight wiring [WayBack] and crossed wiring [WayBack]:

All work fine for CAT5, CAT5E and CAT6.

–jeroen