Can someone explain CAT5 pairs?

[Bardic]

OK, A guy called our service shop because he was having problems with his network. I was trying to troubleshoot with him a little and asked what color combination he used to make his cables. He said color didn't matter, as long as it was the same on both ends.

I said, Yes, that was true, but that the pairs did matter. I asked him how he did his, and as I expected, he said

Brown
B<font color=yellow>r</font color=yellow>o<font color=yellow>w</font color=yellow>n
<font color=green>Green</font color=green>
<font color=green>G</font color=green><font color=yellow>r</font color=yellow><font color=green>e</font color=green><font color=yellow>e</font color=yellow><font color=green>n</font color=green>
<font color=blue>Blue</font color=blue>
<font color=blue>B</font color=blue><font color=yellow>l</font color=yellow><font color=blue>u</font color=blue><font color=yellow>e</font color=yellow>

and I stopped him and told him he was wrong, and then spent the next 10 minutes trying to convince him that it does matter where certain wires go.

Finally he said this wasn't getting him anywhere and just hung up on me (which really ticked me off since he was the one who called for help).

So, in talking with some others they said it has something to do with waveforms and that the signals have to sync up with each other. Can someone maybe explain a little better, so if this happens again I can hopefully describe the reason the pairs are arranged the way they are?

P.S. OK, so I went a little markup crazy (except there isn't a brown and white isn't readable), and for those who don't know, the standard is:

Brown
B<font color=yellow>r</font color=yellow>o<font color=yellow>w</font color=yellow>n
<font color=green>Green</font color=green>
<font color=blue>B</font color=blue><font color=yellow>l</font color=yellow><font color=blue>u</font color=blue><font color=yellow>e</font color=yellow>
<font color=blue>Blue</font color=blue>
<font color=green>G</font color=green><font color=yellow>r</font color=yellow><font color=green>e</font color=green><font color=yellow>e</font color=yellow><font color=green>n</font color=green>
<font color=orange>Orange</font color=orange>
<font color=orange>O</font color=orange><font color=yellow>r</font color=yellow><font color=orange>a</font color=orange><font color=yellow>n</font color=yellow><font color=orange>g</font color=orange><font color=yellow>e</font color=yellow>

 

[camieabz]

<A HREF="http://www.mplsgeeks.com/networkcables/cableprint.html" target="_new">Link</A>

Hope this helps.

<b><font color=blue>~ <A HREF="http://forums.btvillarin.com/index.php?act=ST&f=41&t=324&s=58e94ba84a16bedfebbf0f416d5bac48" target="_new">Nice sig 81.</A> ~<font color=blue></b>

 

[Bardic]

Absolutely perfect, that was exactly what I was looking for. Thanks.

I still have to figure a way of explaining it to people, but this helps a lot.

 

[jihiggs]

the quick and dirty answer:
each signal pair must be twisted. this cancels any external frequency that can be radiated to other pairs.

my computer is so fast, it completes an endless loop in less than 4 seconds!