RJ45 standard

I have always crimped my own network cable. I have done both ends the same,
which seemed to work fine.
Just recently I found out there was a "standard."
http://yoda.uvi.edu/InfoTech/rj45.htm

My question: is this standard just a way to make sure it's done the same way
each time, or is there another practical reason?
Should I go back and re-wire all that cable I ran previously?

Matthew

Matthew wrote:
> I have always crimped my own network cable. I have done both ends the same,
> which seemed to work fine.
> Just recently I found out there was a "standard."
> http://yoda.uvi.edu/InfoTech/rj45.htm
>
> My question: is this standard just a way to make sure it's done the same way
> each time, or is there another practical reason?
> Should I go back and re-wire all that cable I ran previously?
>
> Matthew
>
>
>
It's vital to get full performance that the pairings be correct.

You could violate the particular color scheme and get away with it
(although it could confuse those who come behind you) as long as
each twisted pair (e.g. orange & orange/white) is attached to
positions that are paired in the standard. (For historic reasons
there are actually A and a B standards, and either can be used, as
long as you're consistent.)

If you violate the pairings, you are inviting crosstalk and noise
problems.

--
The e-mail address in our reply-to line is reversed in an attempt to
minimize spam. Our true address is of the form che...@prodigy.net.

Matthew wrote:
> I have always crimped my own network cable. I have done both ends the same,
> which seemed to work fine.
> Just recently I found out there was a "standard."
> http://yoda.uvi.edu/InfoTech/rj45.htm
>
> My question: is this standard just a way to make sure it's done the same way
> each time, or is there another practical reason?
> Should I go back and re-wire all that cable I ran previously?
>
> Matthew
>
>
>
You really ought to go back and re-wire if you don't have the pairs
correctly wired. The color isn't that important as the signal can't tell.

Some years ago I didn't know there was a standard. I just started with
one pair and then the next, and the next and finally the next. I did
the very same thing on the other end. Everything worked fine (at 10
mbs). One of my machines was in the next building and was 60 ft away.
When I upgraded to 100 mbs everything stopped working in the other
building. Finally I discovered the standard, made up two standard ends
and 100 mbs was fine. With the pairs in a row, you have a signal using
one wire of one pair and one wire of another pair.

I knew a friend was having the same sort of trouble at work. I called
and told him of my finding. He had gone so far to as to set up two
machines and kept cutting the wires shorter and shorter. He found that
30 ft was about the max distance at 100 mbs he could get with the pairs
in a row.

After he changed so the signal was moving through twisted pairs, the
distance problem was gone.

Sure surprised me.

John

> I knew a friend was having the same sort of trouble at work. I called and
> told him of my finding. He had gone so far to as to set up two machines
> and kept cutting the wires shorter and shorter. He found that 30 ft was
> about the max distance at 100 mbs he could get with the pairs in a row.
>
> After he changed so the signal was moving through twisted pairs, the
> distance problem was gone.
>
> Sure surprised me.

That's amazing. Well, most of my wires are very short distances (under
30'). However, there are a couple of 200 foot stretches I plan to re-do.

Thanks for your comments!

Matthew