Can you use phone lines for ethernet?

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borgia

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#20540 29-Mar-2008 16:39

I have a really old brick house that it is impossible (nearly) to wire through. The previous owners did spend a lot of money putting phone lines in with standard jack points though. Is there any way of cobbling together an adaptor from an RJ45 to a phone cable? I know that gigabit is 4 twisted pairs, and it looks like the phone has 4 wires, so I know that is out, but I would easily settle for 100MBs. Wireless doesn't cut it for media streaming in the brich house. Sorry if its a stopid question.

Ivan

cyril7

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#119568 29-Mar-2008 16:47

Is the cable used for the phones cat3, normally white with two pairs (blue/white, and Orange/White), or is it cat5/cat5e normally this is blue with 4pairs within.

If cat3 you will get 10BaseT and if lucky, and I mean very lucky you might get 100BaseT, this assumes the line is very short (ie <10-15meters) and in good condition and just a single uncut length, it might, I repeat might work. It would be easiest to replace the phone jacks with surface mount RJ45s.

Cyril

borgia

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#119635 30-Mar-2008 06:55

Cool thanks for that. Ill give it a try. I assume there ust be wiring diagrams in google land.

Ivan

cyril7

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#119645 30-Mar-2008 09:21

Hi Ivan, Did you establish what type of wiring it is, sounds like cat3 if only two pairs. Its is very important that you know what wires are what, ie outlet A goes to outlet B and has not stop off inbetween. Obviuosly you cannot have phone on the same cable at the same time.

For 10/100BaseT you will need to have the green and orange pairs of a RJ45 taken from each end to the other. I honestly would only espect your NICs to connect at 10BaseT but it will be more reliable than Wifi in a poor signal environment.

Cyril

borgia

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#119647 30-Mar-2008 09:30

Its cat3, unfortunately. The previous owners had two phonelines into the place, so there are two jackpoints in most rooms. When i plug a phone in one is live and one is dead. Telecom have said in the past we can have two different phone numbers. As for the nature of the cabling, it is buried in brick, running behind walls, disappearing into unaccessable roof spaces, so I am going to have to just plug it in and see what works.

Thanks for your interest and advice!

Ivan

cyril7

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#119650 30-Mar-2008 10:00

Hi, I strongly urge you ensure that the line you are testing is not connected to the exchange, your NIC may not like it.

Cyril

borgia

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#119651 30-Mar-2008 10:03

Does that mean not connected currently or physically disconnected even though it is not 'live'.

Ivan

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cyril7

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#119655 30-Mar-2008 10:27

The line needs to be dead, that means that its disconnected from the inbound line. Even if you dont have phone service telecom dont always physically disconnect your line, it may still have bias and could potentially ring.

Cyril

webwat

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#120949 4-Apr-2008 00:47

A 100 Volt ringing signal would do interesting things to your ethernet network. Sometimes you might see cat5 wires with the blue and orange though. Treat the blue wire as if its green. If either of the jackpoints have more than 1 cable connected then find out which cable goes to your other jack, probably trial and error...

Time to find a new industry!

Mark

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#126164 24-Apr-2008 15:53

In my house the previous owners had done a fantastic job of completely stuffing the internal phone lines :-)

However what I did was to remove the wall plates at all the points, disconnect the wiring, then tied my nice cat5 cable and a cat6 cable to the end of the existing wire, run to the other end of the old wire, and pull my new wire through .. this then left me with more pairs to play with for phone lines and a cat6 line for ethernet.

You might be able to do the same .. assuming they've not stapled the existing cable onto anything and there there are no major obsticals to pull the new lines past.

Also if you can don't daisy chain the phone jacks together, try and do a star topology for the phone lines where your main line comes in and you have a patch panel splitting off to the different rooms ... gives more flexibility and less chance of dead phone jacks if you have a single cable fault.

euanandrews

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#126194 24-Apr-2008 18:32

Another option, rather than messing with your phone lines...have you thought of ethernet over power lines?

Search 'HomePlug'

richms

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#126605 27-Apr-2008 17:29

Did the same in an associates apartment that had cat-3 daisy chained between all the outlets - put a 2 rj45 outlet wall plate where each phone outlet was and put a switch there with the local devices plugged into it. The adsl router was put where the master socket was, so by the time the line got to the #3 bedroom it had being thru 4 switches. Still worked ok for internet but lan transfers were a bit slow. The twist rates not _that_ different between cat 3 and 5 so you should be fine.

Richard rich.ms