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There are only two unique cable ends in the preceding diagrams. They correspond to the 568A and 568B RJ-45 jacks and are shown to the right. 

Again,  the wires with colored backgrounds may have white stripes and may be denoted that way in diagrams found elsewhere.  For example, the green wire may be labeled Green-White--I don't bother.  The background color is always specified first.

Now, all you need to remember, to properly configure the cables, are the diagrams for the two cable ends and the following rules:

  • A straight-thru cable has identical ends.

  • A crossover cable has different ends.

It makes no functional difference which standard you use for a straight-thru cable.   You can start a crossover cable with either standard as long as the other end is the other standard.  It makes no functional difference which end is which.  Despite what you may have read elsewhere, a 568A patch cable will work in a network with 568B wiring and 568B patch cable will work in a 568A network.  The electrons couldn't care less.

My preference is to use the 568A standard for straight-thru cables and to start crossover cables with a 568A end.  That way all I have to remember is the diagram for the 568A end, that a straight-thru cable has two of them, and that the green and orange pairs are swapped at the other end of a crossover cable.

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