Snafui.com - Cat5 Cabling Diagram

EIA/TIA T568B Standard Cable

Con 1 Pin #	Wire Color	Con 2 Pin #
1	Orange/White T2	1
2	Orange R2	2
3	Green/White T3	3
4	Blue R1	4
5	Blue/White T1	5
6	Green R3	6
7	Brown/White T4	7
8	Brown R4	8

EIA/TIA T568B Crossover Cable

Con 1 Pin #	Wire Color	Con 2 Pin #
1	Orange/White T2	3 *
2	Orange R2	6 *
3	Green/White T3	1 *
4	Blue R1	4
5	Blue/White T1	5
6	Green R3	2 *
7	Brown/White T4	7
8	Brown R4	8

Essentially your oranges and greens trade
places on one end of your crossover cable.