very basic cable question

Question

Looking at building my own Ethernet cables. Reading a bunch of stuff about pairs and pins, it seems like if you just make sure that the wire at one end is wired to the same pin on the other end, everything will be OK no matter what color or stripe the wire has. I looked at several prewired cables I already have, and none seem to conform to the 568A or B standards. Am I missing something here or can I just wire the pairs through to the matching pinouts?

johnbeetem · Answer

The colors don't matter electrically, but using the standard colors might reduce errors. Make sure you wire the pairs correctly and that you don't exchange the wires of a pair. Pins 1+2 are a pair, as are 3+6, 4+5, and 7+8. Here's a Wikipedia page: https://en.wikipedia.org/wiki/Ethernet_physical_layer#Twisted-pair_cable

johnbeetem · Answer

The standards are much more important when wiring inside the walls of a building or wiring to a building. In that case, you really want to use a standard so you can get the wiring right the first time and your installers don't have to think about it. If you are making cables for connecting devices together and not going through walls, which standard you use isn't so important. Just wire the cable straight through as you have said, and make sure 1+2, 3+6, 4+5, and 7+8 are paired since they carry differential signals. 10baseT and 100baseT only use 1+2 and 3+6. 1000baseT uses all four pairs.