[ale] rj45 & rj11

James P. Kinney III jkinney at localnetsolutions.com
Fri Dec 6 22:27:19 EST 2002


The rj11 plug is smaller than the rj45. It will line up in the middle.
It will not fit very well as both te width and height is smaller than
the rj45.

It is not uncommon to run phone through cat5 wire as it is perfectly
compatible. As ethernet only uses 2 pair of wires in the cat5 bundle, it
is possible to run phone signal down the other two wires. It should not
cause cross talk issues as the phone line frequency is much lower than
ethernet. The ethernet, however, might cause a faint hiss on the
analogue phone. Piggy-backing a digital phone system on the same cable
with ethernet is not a good idea. The first pair of phone wires is
"data", the second is "control". The control signal can be scrambled by
ethernet on adjacent wire pairs.

To run (analogue) phone and ethernet using the same cat5 cable will
require that the wall plates be double socket types, one cat5 RJ45 and
one RJ11. The Orange/white and green/white wires are used by ethernet in
10Mbit traffic. The blue/white pair, while not used has a different
internal cable twist and tends to act as a bit of a "buffer" for 100Mbit
systems. Thus, the brown/white pair is available in a 100Mbit connection
for phone.

However, if one is running cat5 wire for data, just go ahead and pull
some cat3 phone line at the same time! It's cheap and won't be any more
trouble than pulling the single cat5 line.

A final note, many commercial phone systems use cat5 and rj45 hardware
because they use more lines with a higher frequency and thus they
require computer grade hardware.

On Fri, 2002-12-06 at 20:42, Stephen Turner wrote:
> hey i was curious, i seen a little talk previously about running telephone
> lines and dsl/lan lines through cat 5 and rj45 connecters.... do rj11
> conecters work with rj45? how do the wires line up? is there a website or
> place i can go about this? cause running both lan lines and telephone
> together sounds neat and i would like to reasearch this further.
> 
> __________________________________________________
> Do you Yahoo!?
> Yahoo! Mail Plus - Powerful. Affordable. Sign up now.
> http://mailplus.yahoo.com
> _______________________________________________
> Ale mailing list
> Ale at ale.org
> http://www.ale.org/mailman/listinfo/ale
-- 
James P. Kinney III   \Changing the mobile computing world/
President and CEO      \          one Linux user         /
Local Net Solutions,LLC \           at a time.          /
770-493-8244             \.___________________________./

GPG ID: 829C6CA7 James P. Kinney III (M.S. Physics) <jkinney at localnetsolutions.com>
Fingerprint = 3C9E 6366 54FC A3FE BA4D 0659 6190 ADC3 829C 6CA7 



 This is a digitally signed message part




More information about the Ale mailing list