Subject: Re: Cat 5 wiring
From: Jon Reynolds (jonr@destar.net)
Date: Wed Sep 18 2002 - 09:05:47 AKDT
Man! Thanks for all the responses to this question. Every time I went to
post another question about this someone else answered it in another
email!
I am doing some wiring for a small business and they asked me if they
could use some of the wires for a telephone line. I knew about the
signal being degraded but I also knew that not all pairs were used. It
is going to be my recommendation that they NOT use the other pairs for a
secondary telephone line.
After reading these responses I am thinking that it would be more
trouble than it is worth. I don't want to have to troubleshoot weird
errors and have them dissatisfied with my work.
Thanks for all the input and the great avice, I am going to follow it.
:)
Jon
On Wed, 2002-09-18 at 00:17, Joshua J.Kugler wrote:
>
> Ummm...I need to pull out my Leviton manuals to check, but...
>
> IIRC, you may wire all 4 pair for spec compliance, but when it comes down to
> it, only two pair are used: One TX pair and one RX pair. Cross-over cables
> -- 10bT and 100bT both -- only swap two pairs: the TX and RX pairs. The
> reast aren't used.
>
> Granted, you'll never be truly CAT 5e compliant (hmm...should check that too)
> if you split your pairs into two runs, but I do know it is done often.
>
> j----- k-----
>
> On Tuesday 17 September 2002 22:45, Arthur Corliss wrote:
> > > That is correct - pins 3 and 6 are receive and pins 1 and 2 are
> > > transmit. The rest are not used.
> > >
> > > How you would use the other 4 I don't know - presumably stripping
> > > the insulation back aways and splitting it - which would seriously
> > > degrade your reliability. I would say theoretically there's no
> > > reason you couldn't, but you probably would lose more than it's
> > > worth in bad packets (especially with 100mbit ethernet)
> > >
> > > Just my 2c - It'd be fun to try it and do some tests though! :)
> >
> > That's not accurate: two pairs are used for 10bT, but 100bT requires all
> > four:
> >
> > ----100Base-T----
> > EIA/TIA-568A:
> > 1) T3--Wh/Gr
> > 2) R3--Gr/Wh
> > 3) T2--Wh/Or
> > 4) R1--Blu/Wh
> > 5) T1--Wh/Blu
> > 6) R2--Or/Wh
> > 7) T4--Wh/Br
> > 8) R4--Br/Wh
> > EIA/TIA-568B (AT&T 258A):
> > Reverse pairs 2 & 3
> >
> > ----10Base-T----
> > IEEE:
> > 1) T2--Wh/Or
> > 2) R2--Or/Wh
> > 3) T3--Wh/Gr
> > 4)
> > 5)
> > 6) R3--Gr/Wh
> > 7)
> > 8)
> >
> >
> >
> > --Arthur Corliss
> > Bolverk's Lair -- http://arthur.corlissfamily.org/
> > Digital Mages -- http://www.digitalmages.com/
> > "Live Free or Die, the Only Way to Live" -- NH State Motto
> >
> >
> > ---------
> > To unsubscribe, send email to <aklug-request@aklug.org>
> > with 'unsubscribe' in the message body.
>
> --
> Joshua Kugler, Information Services Director
> Associated Students of the University of Alaska Fairbanks
> isd@asuaf.org, 907-474-7601
>
> ---------
> To unsubscribe, send email to <aklug-request@aklug.org>
> with 'unsubscribe' in the message body.
>
---------
To unsubscribe, send email to <aklug-request@aklug.org>
with 'unsubscribe' in the message body.
This archive was generated by hypermail 2a23 : Wed Sep 18 2002 - 09:07:04 AKDT