How do you wire a telephone extension?

Can I have both a telephone wire and Ethernet wire running through my cat 5 port in my house at the same time?

• I have a telephone line running though the house in the cat 5 port currently. I was wondering if I could run both a Ethernet and the telephone wire through the cat 5 ports and still ...show more

• Answer:

  If it is a real CAT5 port with 8 connections it will carry network signal on the 1 and 2, and 3 and 6 terminals. That is the Orange and White/Orange, and the Green and White/Green pairs. The blue pair is not used. But on most routers, computer network cards and switches the blue pair are shorted to protect against spurious signals and surges. You would need to run proper CAT5 cable between the outlets. You would then need to modify a patch lead by cutting out the blue pair at one end and fitting a proper RJ11 pug or wiring it into a RJ11 outlet wall box. Or whatever alternative your country uses. Be aware you can cause serious damage if you get it wrong, and if you directly connect a modified cable to the PSTN (public service telephone network) you are breaking the law, can be prosecuted and have your address blacklisted so no provider will connect a telephone line to it.