Our apartment has S-Bus ports in certain rooms. Apparently this had something to do with a previous ISDN installation.

Is there anyway of converting this to Ethernet without pulling new cables?

Over short distances you could potentially run ethernet. Any cable specification can be violated - the only question is whether or not it works, or whether it interferes with other devices. You won't be able to run gigabit - but you might manage 100Mbit, but you'd have to cable it yourself.

The cable used for the ISDN wiring is similar, but most likely not up to the standard required for ethernet. This doens't mean it won't work however.

Consider the cost of buying crimpers for the RJ-45 connectors and a few bits of cable, RJ-45 sockets, plus the time involved - would it be worth it. Try getting yourself a wireless bridge instead - cheap and no cables to mess around with.

If you really want to do this pull out a little bit of the cable - check to see if you can see "Cat 5" stamped on it - if so, this is the same cable used for 100Mbit Ethernet. When you connect it make sure you match the pairs (transmit) receive to the pairs (which are likely to be slightly twisted) in the cable itself. You can find the pin-outs and cabling details via google I would suspect.

Problem is S-Bus (S0-Bus apparently) uses RJ45s, but only 4 wires. The remote connection here uses the other 4 wires in the cable for normal analog telephone.

I'm already running a wireless bridge, unfortunately the walls are pretty thick here (or some other interference) and the transfer rate is poor. Also my D-Link 11g access point failed, so I am back to an 11b. I am not in the mood to keep replacing APs.

I've got a spare 25m Cat 5 lying around, but the outlets at each end which match our apartment are 50chf each.

If I can draw the Cat 5 I'll run with it, if not I'll stick with the bridge.

How reliable and efficient are the powerpoint LAN connectors?

The 4-wire thing may actually be OK - while the ethernet spec calls for 8 wires, you actually only use 4 of them. At a previous employer, we used to run either two ethernets or one ethernet and one serial over the same 8-wire drop, depending whether we needed two computers or a computer and a serial terminal at the other end. It worked fine until we got over about 75 meters, then it started to have problems.

Of course I don't actually remember _which_ four wires to use, but presumably the internet can tell you that.

I've got the crimper, punchdown and extra RJ45 male ends. You are more than welcome to use them if you want. I can also help with the wiring since I did it a lot in my younger years.

I have a pair of those from the days when I was running ethernet-over-power to my cellar. Work a treat...!

Recently did this in a location where a lift was blocking the wireless signal. Didn't get anywhere near the advertised rate, and found that the rate depends very much on whatever cabling and other electrical stuff was in between. I found that on one end I had to plug the thing directly into the wall - if I plugged it into a powerboard there was no connection possible. I think I ended up with about 12Mbps in the end which was fine for internet.

These powerpoint things are great when you are in a bind, but they are a little expensive. Keep the receipt in case it doesn't work well in your house.