Cat 5E cabling.

Brian,

a) difficult for me to say what you already know b) it is common a occurrence to find both 568A and 568B in patch cords c) doesn't make any difference in a practical sense

I have seen patch cables sent out with Cisco routers and they don't even conform to any known wiring colour or terminating standard. Needless to say they are all Chinese origin. While the Australian recommendation is for structured cabling to be terminated to 568A there is no problem with doing it to 568B.

"Brian Goldsmith" wrote

I have just purchased two Cat 5e A type patch cords of different length and manufacture.Whilst both are wired identically (straight through,1 to 1 etc.),I notice the colour codes used are different,one following the 568A code and the other following the 568B code.Could someone advise if a) there is something about Cat 5E I don't know (very possible),b)this is "common" practice and c) it really matter,electrons cant see colour after all!

Thanks,Brian Goldsmith.

***** Well,I believe the answer is first of all,a) followed by b) followed by c)!!!!!!!!!!!!!!!!!!!

Please see the following which I have just discovered in a google search.

"The 568 committee, with good intentions, decided to allow both wiring methods (568A & 568B) to exist within the 568A Standard. The reason was that at the time, a great deal of cabling plants had been installed to the B standard (formerly known as WECO or AT&T 258A). Even though they allowed both wiring methods, they stated in their standard that 568A wiring would be the preferred method for all new installations. Time, and popular opinion, went in the other direction. The most popular wiring method today is 568B. Having both A & B methods does nothing but cause errors and confusion. Originally, patch panels and jacks were manufactured either A or B. In most cases, they were not labeled as such. Most suppliers stocked only the B wired products. Luckily, today, almost all jacks and patch panels show diagrams for both A and B. The only difference between the two is the interchanging of the 2nd and 3rd pairs (white/orange and white/green, respectively)."

What a typical septic dogs breakfast!!! :-) A bit like the US satellite that "blew" up because the septics couldn't recognise there were some parts made to metric specs and some made to US Imperial!!!

Thanks for the indulgence!

Brian Goldsmith.

This is the page I refer my workmates to when they want to know how to make a custom length of patch cord.

It cuts and pastes to Word and prints out well. The hard part is developing the manual dexterity to untwist those damned little wires, trim them to the right length and get them into the plug for long enough to crunch down on the crimping tool. As it says, there's no diff in connectivity between straight thru 568A and

568B, though most patch cords seem to be 568B. Naturally, if you need a crossover cable you need one A end and one B end.

PH