combining phone system with ethernet

ok please dont flame me about this as im new !!

i just wanted some advice on the following :

at the minute, ive got a network installed in my house which consists of a few cat5 ports running wires into a standard switch.
I wanted to know if I could easily incorporate my phone system into the same network setup without the need for much additional hardware.
I only have 1 telephone line to the big wide world, so i wanted to know if i could piggyback the telephone system on the same wiring system I currently have setup for my ethernet.
Im not sure on power outputs of the telephone system (i think its 12v??) - its standard BT (in the UK) so i wasnt sure if this power would affect my ethernet at all, or whether I would need an entirely different network to get my telephone spread around the house.

Any thoughts would be greatly appreciated

Thanks :)

ps i dont actually have IP phones, i just wanted this solution as i find it easier working with ethernet rather than with both ethernet and rj45 cable
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  1. Unfortunately no. While 2 pairs on the Cat5 are not used for 100mbit Ethernet, there is no way the switch is going to carry over your phone signals.

    If you really want to do it you can strip the wires near the switch and use the blue or brown pairs for your telephone. This would be rather messy and also could cause interference in the network (since the wires would be against each other unshielded).

    I would not recommend that you do it unless you are really desperate or like to experiment. Your best bet is to use different wiring for the telephone.
  2. ok thanks, i thought that might be the case.

    are there special switches you need to buy for telephone systems - ive read a lot about PoE ?? otherwise can i just buy a normal ethernet switch and use that for my telephone system ?

    thanks :D
  3. You don't need power over Ethernet or anything else.
    If it is just one line that you want to connect a few extensions to all you need is to connect the wires in parallel. Couldn't be any simpler :)

    There is no need for a switch or any outside power source. Note I have no experience with the UK phone system so I could be wrong here but that is the way it works almost everywhere else.

    Good luck with the project and remember to be neat with the wiring or u'll have hell to answer to the wifey :)
  4. You can use the same cable for both ethernet and phones.

    10 or 100 Meg ethernet only uses 2 out of the 4 pairs in the cable so you could have the same cable carrying phone and ethernet. I've been on many sites where they have done this. What will not work however is Gigabit as this uses all 4 pairs in the cable, and you will need at least cat 5e cable for gigabit.

    You do not need a POE ethernet switch unless you are going to use an IP phone. The standard BT/NTL phone is not an IP phone

    You also need to remember that the connection from the master telephone socket in the UK is 3 wires. 1 Pair for the connection and the 3rd wire for the ringing. You will need secondary phone sockets for the phones. I cannot remember what pins in the phone socket should be wired.

    I think you need to look at what you want to do. The standard phone plug is a different connector to the ethernet RJ45, so if you wired up your phone cable to ethernet sockets the telephone line cord would not fit. If you are not going to use gigabit ethernet then you can use the spair 2 pairs in the ethernet cable and wire these to a phone socket in each room. If you are going to use gigabit later run in seperate cable for the phones, they only need 2 pair cable so that may be cheaper than UTP ethernet cable. Use cat 5e or cat 6 for the ethernet cable.

    Have you thought about a digital cordless phone, it could save a great deal of trouble.

    Rob Murphy.
  5. I to have seen people using one cable for both which I did state but I have noticed some interference when the phone rings. Nothing serious but nevertheless................

    Didn't know about the UK using 3 wires.
  6. hi

    we have a voip system set up, ie phones around the officeconnected via ethernet

    just to let you know you can get converters from RJ11 (phone) to an RJ45 (ethernet).

    my question is , we have 2 switches linked with a uplink cable that work fine, with the phone system in the one box/cabinet/switch

    and all phone systems working fine

    but we want to attach another phone to the system on the 2nd switch system thats about 60 meters away though rooms.

    and therefore looking at an easy way to attach a phone without another link cable.

    i had thought about splitting the link cable so that i can have the network link AND phone running along side each other.the link works but the phone wont. i am using a "T Base Splitter" ,

    brain wave, does this not work because, because its a link cable it uses 4 pair for recieving and 4 pair to transmit the data, in effect acting as a gigabit data rate though it?

    any ideas appreaciated



    Managing Director

  7. the only thing i dont get is i split the cables and the link worked still,

    and i also used the other splitted side connected to aaccess point (in the wall) and the computer worked fine linked over the cables and added to the system switch furthest way, (using the link cable to do)
  8. This "run multiple things over one Cat5 cable" need is more common now with cable boxes and other AV equipment by your TV wanting Internet and phone jacks, as well as the traditional uses, and so it is worth keeping this thread alive. In case anyone new is trying to do this sort of thing, and has Cat5 and is willing to accept the 10/100 Ethernet limitations (not really that bad in most cases) consider information at "" which explains with diagrams how one can split up the cat 5 8 wires (4 pairs), and then consider that one side of this split could be phones (up to two phone lines).

    The split side of pre-built jacks that do two 10/100 network lines on one cable without you having to re-wire your cat5 ends is commonly available all over searching for "cat5 splitter" on Google, but having a phone jack and an Ethernet jack is not so common. I did find "dualcomm" on eBay selling ethernet/phone as "2X RJ45/RJ11 Splitters For Phone/Ethernet Line Sharing". To this sort of solution, you need two for each run of wire (one at each end). For networking, be sure to get Base-T stuff, and not mistakenly some Token Ring stuff (both use wide 8 wire RJ45 ends).

    The items I talk about above do not really address the sharing of phone around a whole ethernet network, because as "choknuti" notes switches and routers are not going to carry that stuff. VOIP is better for that. Instead, it applies to individual runs of wire, and the wiring itself naturally forces 10/100 and separates the lines removing your need to think at all (plug-n-play). But, in many cases, and perhaps even the original one that started the thread, that might be just fine. In specific, Dish Network boxes in 2009 benefit from both a phone and Ethernet connection which is what prompted me here; using this sort of solution your old Cat5 wire might come in handy.
  9. How about using something like these bad boys.. I think they tap into the unused wires on ethernet to carry the phone signal. You should a pair one for each end of the cable being used.
  10. Would you look at that this thread was brought back from the dead a total of 2 times, back in 2009 and now.

    Please start a new thread linking to the old.
  11. @vanwahlgren: The original thread is from 2007... Please don't bring up old threads!!
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