basic phone and ethernet over same cat 6 cable

jgas · Dec 29, 2013

I have run cat6 throughout my house during a remodel. I would like to use the same cable for both basic landline phone and for internet. Are there enough pairs in cat 6 so that I can use the same cable for both a rj11 and rj45 jack? Will I compromise speed doing this? Thanks, I am a rookie so I need fairly simple answers.

CaedenV · Dec 29, 2013

Ethernet technically only needs 4 wires (2 pairs) to transmit and receive data. So yes, technically you could use 2 pairs for your Ethernet, and then have 2 phone lines (one pair each) running throughout your home. My elementary and middle schools resorted to do this when they were faced with major budget cuts and could not properly remodel the dated wiring.

However, this is a horrible idea. You will halve the throughput of your network, and bring in interference issues between your phone and data systems. Also, you will need to custom wire each and every jack in your home to do this.

It would be far better to have separate Ethernet and phone lines throughout the home, or else get a decent wireless phone system that will work in your home without needing to interfere with your wired network.

You will need to research the best wire pairs to use with the least interference if you want to do this. But I would highly suggest against it.

jgas · Dec 29, 2013

Thanks for the reply. I am using DSL and only getting 10-12mbs speeds. I thought if I had Cat6 and used a pair for phone in a couple of rooms that I would at least get 100mbs speeds preserved were I to get a faster internet source in future. Is it really that big of an issue to use a single pair for the phone?

bigwoofer · Dec 29, 2013

The tight winding of the pairs limits ingress and egress of the data signal. I would think when you're "off-hook" there would be no difference in the speed of your network since there's no 'loop' active in the line when off hook.

Wiring the jacks is a different story, I'd think with your new jacks and modular inserts to accomodate all this, including the custom mod-plugs you'd need to make on the patch-panel side you'd be nearing the price of a nice little multiple-cordless-handset system.

I've been a cable-tech-and-phone-technician for over ten years and done exactly what you're doing in tight spots before and tested it with success. But I never tested the speed loads to see the difference in performance. I'm really curious what the effect would be, assuming there is no noise on the phone line (this is when, with a butt-set, you go 'off-hook' and hear static/noise when there should be none.

bill001g · Dec 29, 2013

If you can live with 100m then it is fine. You do not want to actually wire the jack any differently....unless you plan to plug a phone and pc in at the same time.

What you can normally do is wire everything rj45 jacks. In the central location if you use a patch panel you can do the same. The trick is that you can plug a rj11 plug into a rj45 jack and it will work fine. If you decide you would rather have it used for a pc you unplug the rj11 and plug in a normal rj45.

This of course does not work if you want to run the phone and computer at the same time. Then you will need to physically split the wires and cable to 2 different jacks.

CaedenV · Dec 29, 2013

jgas :

For internet speeds you will not see much (if any) performance hit because you are barely running a 10/t connection, so 100 or 1000/t Ethernet is still going to be vastly faster unless you end up with significant packet loss. The performance hit would be on local network performance when transferring data on the local network. And for that matter, if you are only running internet at 10-12Mbps then you would have done just fine with a CAT5 cable job. My own house is on craptastic CAT5 that I picked up at Lowes and I still have no issue getting gigabit Ethernet speeds in the house between machines... granted none of my cable runs are very long (longest is ~30 feet).

Your only good options here are to either get a good cordless phone system, or else abandon the phone line entirely and get a VoIP system and trade your phone savings for a better internet connection.

CaedenV · Dec 29, 2013

bill001g :

Who would want to essentially rewire their setup every time they want to make or receive a phone call? Never mind that RJ11 and RJ45 connectors don't exactly fit into each other without adapters (RJ11 being 1/2 the size).

jgas · Dec 29, 2013

Thanks Bill for your reply. I was planning to use the cat6 cable for both phone and internet in only 2 rooms and I was intending to split the pairs and wire the jacks separately. Where I have my main desktop computer I could just use the Cat6 for that application only and preserve all the pairs for ethernet if that is truly a better way to go.

If I physically split the wires and hook a pair to a rj11 and the rest of the pairs to a rj45 do you think I should still be able to get 100mbs from my rj45?

bill001g · Dec 29, 2013

CaedenV :

You have never really worked on this stuff have you. Of course you don't switch it back and forth all the time but it is still easier that sending a cabling tech out to re punch down the jack when you want to. This is pretty standard cabling for a business so it will work in the house.

Why do you not just try to plug a rj11 into a rj45 jack before you make stupid assumptions. The center pins line up exactly.

jgas · Dec 29, 2013

Thanks Caeden. I was not really planning a home network. Just want to use the cat6 for internet for my computer and my TV. I already have some wireless phones, I guess I am old fashioned ( or just dumb ) and think it is better to have a few of the phones hard wired in and I have accumulated a lot of phones over the years to plug in. I just don't want to be stupid about it and mess up the internet speed just for a few extra phone lines.

bill001g · Dec 29, 2013

jgas :

You will get 100m without a issue since it only needs 2 pair. The phone will cause no interference being in the same cable. You only need all 4 pair if you NEED 1g which is unlikley unless you are run big disk NAS systems or streaming uncompress blue ray video

jgas · Dec 29, 2013

bill001g :

CaedenV :

You have never really worked on this stuff have you. Of course you don't switch it back and forth all the time but it is still easier that sending a cabling tech out to re punch down the jack when you want to. This is pretty standard cabling for a business so it will work in the house.

Why do you not just try to plug a rj11 into a rj45 jack before you make stupid assumptions. The center pins line up exactly.

Thanks Bill. If I decide to go all rj45 and then plug a rj11 into it where I want to change to a phone is there something I need to know about the wire color scheme to make sure the phone wires are the wires to the center pins? Forgive me if this is a really dumb question.

bill001g · Dec 29, 2013

If you put RJ45 on both ends of the cable then the wire colors don't really matter since the jack will match up the same on both ends.

If you were to do it only on 1 end and follow the standard color patters for the Rj45 jacks (ie you match the wire colors to the jack). The center pins will line up on blue and blue/white. You can also use the second pair from the center but it will depend on the if the RJ45 jack is a 568a or 568b. most are 568b which means this pair would be green and green/white. Of course it is very uncommon to have 2 phone lines anymore so likely it is just the blue- blue/white you would ever need

Kewlx25 · Dec 29, 2013

jgas :

Depends on how long you're planning on living at your house. You'd be doing something non-standard and will cause eventual issues in the future and will require a new line to be ran.

In the next 5-8 years, expect 1gb-10gb Internet to be making it to houses, assuming you're one of the 80% that live somewhat near a city. 10gb integrated NICs are supposed to start showing up on low-end chipsets in the next 5 years once 22nm makes its way to chipsets.

Again, depends on how long you plan on living at your place and what time-frame you're aiming for.

jgas · Dec 29, 2013

Kewlx25 :

Thanks for your reply. If my central panel and room connections are readily accessible, which they are, wouldn't I just have to replace the jacks to utilize full Cat 6 capability if I decided I wanted the higher speed and just use the pair I took for the phone back with the other 3 pairs? It seems I could recover whatever I lose as long as I leave a little extra cable to work with at both end. I do plan on staying at this house, maybe till I die.

allennnn · Dec 31, 2013

If your doing all this wiring is it really a big deal just to run a phone line to each room at the same time how much is a 200ft drum of phone cable? or a second cat6 to the 2 rooms?

Amazon, 100 Meter Drum 2 Pair 4 Core Indoor BT phone Cable Price: £13.99
http://www.amazon.co.uk/Meter-White-Indoor-Telephone-Cable/dp/B00BC54G98

jgas · Dec 31, 2013

allennnn :

The wiring was all done when the walls were open during a water leak disaster. I should have run more phone cable then but I thought what I was doing with the cat 6 was sufficient.

bill001g · Dec 31, 2013

You just have to get with the times old man and get rid of your analog phones and use cell phones or maybe VoIP phones if you want a physical phone in the house.

My brothers kid told me that all the time and I finally got rid of my analog line only because they raised the rates again

basic phone and ethernet over same cat 6 cable

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