Ethernet over unused twisted pair?

[bill-CIZd1d4GmLheoWH0uzbU5w at public.gmane.org (Bill Horne)]

Scott R. Ehrlich wrote:
> I have no problems making my own cable - please remind me which two 
> rj45 wires (signals) I'd need to wire to the corresponding two wires 
> on the RJ11 side?
>
> Thanks.
>
> Scott
>
> On Sun, 8 Mar 2009, jay-R5TnC2l8y5lBDgjK7y7TUQ at public.gmane.org wrote:
>
>> As long as its a 4 wire phone line and not 2 wire you can run 
>> standard 10/100 over it. They only use 4 of the 8 wires in cat 5. As 
>> for an adapter I'm sure they exist but you could just take a cable, 
>> cut one end and wire up a plug from radioshack or home depot to 
>> convert it.
>>
>> ------Original Message------
>> From: Scott R. Ehrlich
>> Sender: discuss-bounces-mNDKBlG2WHs at public.gmane.org
>> To: L BLU
>> Sent: Mar 7, 2009 8:47 PM
>> Subject: Ethernet over unused twisted pair?
>>
>> I'm trying to find a way to get an Ethernet connection from a second 
>> floor
>> room diagonally across the house to the first floor.    There is no 
>> plenum
>> - no dropped ceiling, and having an electrician do the wiring is too
>> expensive.
>>
>> I _could_ go wireless, but I'd much rather pursue a hardwired option
>> first.
>>
>> So, it occurred to me that DSL is Ethernet than works over a pair of 
>> phone
>> wire.   Is there any device that could convert the Ethernet signal 
>> from my
>> Linksys box to something I could plug into a phone jack that is wired 
>> with
>> the unused phone pair, then run a mating device in first floor's
>> corresponding phone jack and get my hardwired network run that way?
>>
>> Could using two DSL boxes on the wire do the job?
>>
>> Other than an electrician and wireless, what are my options (other than
>> do it yourself or don't do it at all)?
>>
>> Thanks.
>>

Scott,

You need two _pairs_, not just two wires. If your house has "JK" 
telephone wire, which provides four leads, you'll have to switch to a 
cordless phone in order to free the (usually) red & green wires for 
Ethernet.

On an RJ-45 connector, pins 1 and 2 are the first pair, and pins 3 and 6 
are the second. I don't remember which is transmit and which receive, 
but if you're connecting to a router you'll just wire them "straight 
across".

Bill Horne

-- 
E. William Horne
William Warren Consulting
Computer & Network Installations, Security, and Service
http://william-warren.com
781-784-7287