Crossover Cable

From MattWiki
Gigabit T568B crossover
All four pairs crossed
10base-T/100base-TX/1000base-TX/T4 crossover (shown as T568B)
Pin Connection 1: T568B Connection 2: T568B Crossed Pins on plug face
signal pair color signal pair color
1 BI_DA+ 2 Pair 2 Tip
white/orange stripe
BI_DB+ 3 Pair 3 Tip
white/green stripe
2 BI_DA- 2 Pair 2 Ring
orange solid
BI_DB- 3 Pair 3 Ring
green solid
3 BI_DB+ 3 Pair 3 Tip
white/green stripe
BI_DA+ 2 Pair 2 Tip
white/orange stripe
4 BI_DC+ 1 Pair 1 Ring
blue solid
BI_DD+ 4 Pair 4 Tip
white/brown stripe
5 BI_DC- 1 Pair 1 Tip
white/blue stripe
BI_DD- 4 Pair 4 Ring
brown solid
6 BI_DB- 3 Pair 3 Ring
green solid
BI_DA- 2 Pair 2 Ring
orange solid
7 BI_DD+ 4 Pair 4 Tip
white/brown stripe
BI_DC+ 1 Pair 1 Ring
blue solid
8 BI_DD- 4 Pair 4 Ring
brown solid
BI_DC- 1 Pair 1 Tip
white/blue stripe

In practice, it does not matter if your Ethernet cables are wired as T568A or T568B, just so long as both ends follow the same wiring format. Typical commercially available "pre-wired" cables can follow either format depending on who made them. What this means is that you may discover that one manufacturer's cables are wired one way and another's the other way, yet both are "correct" and will work. In either case, T568A or T568B, a normal (un-crossed) cable will have both ends wired according to the layout in the Connection 1 column.