MHC,

Thanks - ethernet it is then

But one thing that has crossed my mind is the connection at the downstairs router end: you are using: "Patch lead from Router to Switch, Patch lead from Switch to Patch Panel, Infrastructure Cable" I was considering simply using a patch lead from router to wall socket then Infrastructure Cable - would the connections have to be based on a crossover between the downstairs and upstairs wall sockets? Or am I totally missing something?

Don't worry about crossovers ... use standard leads and wiring.

As per MHC yes most recent kit either lists itself as "autosensing" and particularly "auto MDI/MDIX".

In general this is taken to mean it will negotiate speed and duplex as well as do an auto-crossover as required.

There are rare combinations where the automatic algorithms lead to a mismatch but this is usually a sign something else is wrong, and can equally happen if one end has been forced to an unsuitable manual setting.

The smart / managed switches we have let you choose what capabilities/modes to advertise in auto-negotiation, without forcing a specific mode.

But as above, you don't need to worry about this unless you know your setup requires something unusual.

MHC and prizx,

Guess I was thinking in terms of a lead, such as a something than has female sockets at each end where the wires are connected differently at each female socket to maintain polarity...

But with "autosensing" and "auto MDI/MDIX" that idea is, if I understand you correctly, irrelevant (I'll have to read up about that stuff - I'm still stuck in the world of SCART plugs and sockets LOL!)

Yes the gist of it is if buying or making up your own cable it can be a normal aka straight-through cable unless you have some things old enough on both ends of a given run, that neither end does the auto stuff.

This illustrates the 2 wiring conventions for ethernet cabling
http://en.wikipedia.org/wiki/TIA/EIA-568#Wiring

When terminating your own cables, you can pick to follow T568A or T568B; it doesn't really matter which as long as you are consistent.

Something that doesn't work is if a connector is wired completely upside down, in the sense that pins 1-8 at one end would connect to pins 8-1 respectively. I believe some 4 or 6 pin telephone systems could cause confusion if the convention for socket pin numbering was reversed compared with plug pin numbering, or if a device expected to be DC powered by the analogue line with a particular pin polarity.

Edited by prlzx (Wed 05-Oct-11 11:03:32)

prizx,

Many thanks for the info and the link.

I've got some cat5e ordered and a rj45 socket - the socket I'll be using upstairs at the computer end as an "output", however I don't feel comfortable about using a rj45 socket downstairs at the router end, as an "input", together with a patch cable. For me a rj45 plug on the end of the cat5e cable connected directly into the router would be a more "logical" setup. That way it "feels" and appears as an extension...any comments about this and possible alternatives, or is having two rj45 sockets linked by cat5e a normal and recognised setup?

Edited by 4M2 (Wed 05-Oct-11 12:36:31)

In reply to a post by 4M2:

For me a rj45 plug on the end of the cat5e cable connected directly into the router would be a more "logical" setup. That way it "feels" and appears as an extension...any comments about this and possible alternatives, or is having two rj45 sockets linked by cat5e a normal and recognised setup?

Yes, when offices are wired for structured cabling, it is sockets at both ends (patch panel in the comms room and sockets mounted in walls or under floor flaps. And other posters have commented on punch-down connections being easier than crimping (which needs more practice).

Sockets at both ends will also be tidier if you need to unplug or move the things later (and cable runs would usually include some spare slack which allows the end connections to be repaired if damaged).

I do understand the "plug end into source socket" way of thinking; in mains wiring there are clear safety reasons why the "supply" end is a socket and the device has the plug!

Similarly analogue telephone lines have a moderate DC voltage and one expects to be plugging something into a phone socket.

But ultimately whichever approach you are more comfortable with, as long as it works.

Edited by prlzx (Wed 05-Oct-11 12:46:51)

prizx,

Appreciate the clarification

Right! Another, post free, rj45 socket is being ordered as I speak...it would certainly be easier to fit, with a healthy connection, than a rj45 plug.

Just wonder what any future property owners/surveyors might think about the two rj45 sockets, although the cable will be visible through most of it's length.

prizx,

Just out of interest: would the rj45 wiring conventions for ethernet cabling, that you linked to, allow for a rj11 to rj45 (or rj11) cable to be used for connecting the downstairs master adsl rj11 filtered socket to the new rj45 downstairs socket should the router be used upstairs at some future time - in other words could the rj45 socket > ethernet > rj45 socket setup also be used as an analogue twisted pair?

Yes good quality telephone cabling and ethernet cabling are both twisted pair and ethernet (certainly CAT5 or above) exceeds the standards that analogue voice requires.

Whereas some telephone extension cables are flat (with no twisting) which are more prone to interference on longer cable lengths.

What is sold as RJ11 cable may have 2, 4 or 6 wires but a single phone line only needs one pair, so the "RJ45" plug would need to connect any one of the 4 pairs (and not split it across different pairs).

An "RJ11 to RJ45" adapter or cable would preferably use the centre pair (pins 4+5). Some adapters linked a second pair for PBX signalling.

100Mbps ethernet only needs pins 1+2 and 3+6 (gigabit uses all 4 pairs) so with care 1 or 2 analogue pairs could be run over the same cable at the same time but not really advisable!

Edited by prlzx (Wed 05-Oct-11 14:25:14)