Do your own thing - how to cable your own house

By David Ryan Master copy here.

So, you want to cable your house ?

First things first - I would recommed going for 10Base-T (4 pairs of cable, like phone cable) rather than 10Base-2 (co-ax, like the TV) unless there are only two or three points which need to be connected. 10Base-T has the advantage that it can be used for phone, data, and anything else which might come along in the relatively near future.

Second things second - this will be messy. It involves drilling big holes in walls and stuff like that. Holes that will need to be plastered around and repainted or otherwise made good. The best time to do this kind of thing is when the house is being built or about to be rewired.

Is this really wise ?

There is also the possibilty in the near-middle distance that you might have some cable data delivery system into your house. Having your house ready would definitely be a good thing in this case. Alternatively you could save a few hundred quid now and wait another 35 years until your house needs to be rewired.

Terminology (as used in this article, not necessarily the scientific explanation) :

• twisted pair cable - this cable is made up of 4 pairs of wires possibly surrounded by a metal sheath, definitely surrounded by a (normally grey) flexible plastic sheath. The twist is *important*. Ordinary 4 pair cable is no use - it must be "twisted pair".

• wire pair - four of these pairs go to make up a cable. The pairs are orange, green, blue and brown. The second wire of each pair is always a mix of the original colour and white. In other words the 8 wires in a cable are whiteorange/orange, whitegreen/green, whiteblue/blue and whitebrown/brown. Each pair is twisted around itself. This twist is vital for signal integrity and must be maintained as much as possible.

• Wall box - what you normally see in an office with phone/data lines hanging out of it. Consists of a plastic box which gets screwed into a hole in the wall or else which sits on the wall, a face plate with a rectangular hole in it and 1 or more RJ45 sockets. The RJ45s click into the face place which in turn screws onto the box.

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Here's what you will need to buy :

• enough cable to wire all relevant points within the house to one central point

• wall plates and RJ45 sockets for each point around the house

• a patch panel for the central location, or else as many wall plates again as you have around the house if you only have a few points

• a small ethernet hub if you have more than 2 computers to connect (or a token ring thingie if you are feeling really brave)

Here's what you will need to borrow *or* buy :

• a krone tool, also known as a punchdown tool (if you are using a patch panel)

• an 8 position RJ45 crimp tool (if you are going to make your own patch leads with all the excess cable you have left over)

• a CAT5 cable tester - one which will indicate a good connection with no crossed pairs, not necessarily one which gives readouts of all the electronic weird stuff (unless you're rich)

• Some known good patch leads from work so you at least have something which works (no seriously, for troubleshooting)

Where to get all this stuff?

If you are getting your house rewired you could always get your electrician to source everything, but unless he or she is used to specifying data components you might find yourself with cable that looks correct, but just isn't up to the task. Don't ask me what you would end up if you asked *me* to source electrical stuff.

When it comes to the cable you can't say CAT5 often enough. If the spec doesn't include the words CAT5 you might be in a bit of trouble. In theory CAT5 cable sould support 100mb/s around your house, but don't expect it unless you spend a lot of time and effort and invest in very good tools to do the job. You shouldn't have any problem getting 10mb/s, even allowing for interference from power cables and poor termination. Anyway, if you are used to no network or some kind of modem/serial/parallel port link you will notice a big increase in speed.

What to do with it all, now that I have it ?

Oh yeah, get them to identify each cable (multiple bands of insulation tape is a good idea) as they pull them to each point. This makes it easier to identify them when it comes to patching later on. Also, get them to dig a hole in the wall to hold the wall box unless you want to mount the box *on* the wall instead of in the wall. Mounting them on the wall looks really awful and is not a good idea. You should also get your telecom cable run to somewhere near the patch panel. This way, you can have you phone in any room in the house just by a quick repatch.

The details of how to get the cable run is up to you, but ensure that the cable doesn't go too near any power cable. Nearish is OK, but the further away the better. If possible, ensure power and data are kept at least 20cm apart. When it comes to digging a hole in your wall make sure you maintain the distance if you want your cable to be any use.

Now I have the cable run, what next ?

Assuming you went for the patch panel option, take the other end of the same cable (you did number them with masking tape didn't you ?) and using the krone tool again punch it into the first set of contacts on the back of the patch panel. You should now have a good connection. Mark on the relevant wall plate the corresponding number on the patch panel.

Stick one patch lead and one part of the cable tester into the wall socket and the other ones into the patch panel. Four good lights ? No ? OK, repunch everything - and you better get used to it. Actually, you should be able to tell which cable pair isn't good from the light which isn't lighting. Eventually you want the same result whether you just stick the tester on a single patch lead, or through your wiring and two patch leads.

Repeat, repeat, repeat.

Assuming your `pooters are correctly configured for networking (I'm not even going to go into this one) you need to patch them into the wall, and patch the corresponding port on the patch panel to any port on the hub which is by now plugged in and powered up. Stand up, close your eyes, clasp your hands and say alashazam and you *might* have a working network.

No. seriously, if your computer works on someone elses network, if the cable tester tells you the connection between the patch panel and the wall boxes is good, and if the patch leads are good then there is *no* logical reason why the network won't work. No magic to it, just connections.

So, how does all this work ?

Alternatively, just patch your phone line into any patch panel port and stick a handset into the wall box on the other end and you phone becomes a moveable item.