[lug] Cat 5e cable color codes

[Nate Duehr]

Let's see, there were a whole bunch of questions posed via the group, so
let me see if I can add some confusion to the subject.  :-)
D. Stimits said:
> I know if I am consistent, and use the same wire straight through on
> all  of the RJ-45 connectors for the ethernet wire, it will work.
> However,  there are color codes, and therefore some "expected or
> traditional"  color-to-pin design. Unfortunately, the color codes on
> the connector are  different than the actual cable colors, so this is
> not entirely
> possible. I am trying to find out recommended color-to-pin for these
> wall connectors.

Dan, if I read this right, you're talking about wall connectors that have
punchdowns inside them where you can't tell which punchdown point is going
to end up showing up on which pin.  The only way to know for sure is to go
by the manufacturer's notes about the connector.  There are some REALLY
stupid connectors out there.
Now, as someone else mentioned, almost all the manufacturers use the
EIA/TIA 568A and EIA/TIA 568B standards.  Some folks sent some nice links
to references, so I won't attempt to reproduce those here as I'll probably
just typo it or mess it up and spread more bad info... (And there's a lot
of it out there...)
I'm not familiar with the NETKEY stuff, but if they followed one of the
standards, you'll be able to get the colors in the wire to match up with
their guts of their connector, and the pins will come out right.  The
trick with all of these is if you're wanting to stick to the standards, to
always buy hardware that follows the same standard.  If you have a bunch
of 568B stuff and then buy a few 568A jacks, you'll end up having to put
those together differently to make them work properly.  Given a continuity
tester and a few minutes, one can fix any Ethernet cable to work...
(GRIN).
Pins 1 and 2 are paired together as one path, and pins 3 and 6 are the
other path.  So if you have a "straight-through" cable, you
continuity-wise you have ...
1,2,3,6 End #1
1,2,3,6 End #2

If you need a "cross-over" cable, you have...

1,2,3,6
3,6,1,2

Some people who have done a LOT of cabling will also call another type of
cable that's NOT useful for ethernet, but is used in telco applications, a
"roll-over" cable...
1,2,3,6
6,3,2,1

And there are those who use the terms "cross-over" and "roll-over"
interchangably.  I don't, but I do slip once in a while and say the wrong
one -- because there's really only two useful layouts for Ethernet unless
you go to Gigabit Ethernet, I think... never played with it.
And as someone mentioned, yes... in some regards the order of the color
code can affect signal cross-talk in the cable, but it usually doesn't
make enough difference to worry about -- but yes -- following one standard
or the other is a "Good Thing(TM)", and as someone mentioned, the older
standard, and the one you'll find in older buildings (especially those
previously owned by AT&T... GRIN... Been there, done that...) will be
568A.
Telco standard color code on a 66-block, blue, orange, green, brown, slate.

Most buildings aren't using punch blocks anymore, but one of the reasons
for 568B was to keep you from punching down analog telco stuff to the same
punchdowns as the ethernet jacks... if you have two 66-blocks side-by-side
and one is punched for analog telco, and one is punched with Ethernet,
you'll be able to quickly and easily see the difference.  The vast
majority of stuff now is modular, and the punching is all done on the back
side of a modular panel, and only done once... so most folks don't have to
worry about all this silliness anymore.
And....(!)... just in case someone is wondering, 66-blocks and 110-blocks
are NOT Category-5 rated.  You'll pick up a small but measurable bit of
cross-talk at a 66-block.  \
3M blocks *ARE* Category 5 rated and require special punch tool bits (they
have a little pair of scissors on them that cuts the wire, they're weird)
and are generally more of pain than just picking up a little noise.
Oh... and someone else asked... how do you know which pins are which.

RJ-45 pin numbers are done left to right, looking as if you were coming in
from the cable side, or if you're holding it vertically... hold it with
the cable downward and the FLAT side of the connector (not the side that
has the little locking tab) toward you.  Pin 1 is on your left.
{The silly trivia you gather when building call-centers with hundreds of
workstations... also, note to anyone doing this... please don't use your
car keys as a weight for throwing cabling through drop ceilings... and
those metal hangars can NOT hold your weight... don't try that either. 
BIG GRIN...)
-- 
Nate Duehr, nate at natetech.com


Random Quote:
--------------
ignorance, n.:
	When you don't know anything, and someone else finds out.