Cat 5E cable and LAN stuff....

Author
Discussion

Byff

Original Poster:

4,427 posts

272 months

Thursday 18th December 2003
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I've got a little network set up at home and now need to expand it a little.

I've got 1 cable going upstairs, but I need two sockets putting up there so was wondering if a LAN uses all of the cores of the wire to communicate?

It would make life so much easier if I can "borrow" one or two cores of this 1 cable to feed two sockets but if I need two cables, then so be it.

Mr E

22,319 posts

270 months

Thursday 18th December 2003
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Errr. Buy a mini-hub? A whole 20 quid or so......

Job done.

Byff

Original Poster:

4,427 posts

272 months

Thursday 18th December 2003
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Ah yes, of course!

I forgot you can join hubs up.

JamieBeeston

9,294 posts

276 months

Thursday 18th December 2003
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Byff said:
Ah yes, of course!

I forgot you can join hubs up.


Need a crossover cable, or an Uplink port on the switch tho (hubs suck, dont use them if you can avoid it, considerably slower top end, and so insecure they make a sieve look watertight)

Deester

1,607 posts

271 months

Thursday 18th December 2003
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Byff said:
I've got a little network set up at home and now need to expand it a little.

I've got 1 cable going upstairs, but I need two sockets putting up there so was wondering if a LAN uses all of the cores of the wire to communicate?

It would make life so much easier if I can "borrow" one or two cores of this 1 cable to feed two sockets but if I need two cables, then so be it.


Your best bet would be to put a router upstairs that is fed from your 1 cat5 cable.

Ebay has tons of cheap routers.

docevi1

10,430 posts

259 months

Thursday 18th December 2003
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Cat5 cables has 2 redunent wires out of the 6 (is it 6?), you couldn't splice the wires successfully. Much better to do what has already been suggested and get yourself a hub/switch/router instead.

malman

2,258 posts

270 months

Thursday 18th December 2003
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Or you can buy a cat 5 splitter for each end as network will run down 4 cores. They go for a couple of quid each. If you already have 2 sockets then don't bother and just wire the single cable into both. Diagrams should be on google.

docevi1

10,430 posts

259 months

Thursday 18th December 2003
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I never knew you could do that It won't get the full speed from the line though will it? I mean the bandwidth will be ultimately halfed?

Marshy

2,750 posts

295 months

Thursday 18th December 2003
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Over 1 run of Cat 5 you can get two ethernets.

Ethernet uses pins 1 2 3 and 6 of the cable, so two pairs out of 4.

I had cat5 run to every room of my house, bar toilets and dining room, when it was built. The sparky didn't folow my instructions though, and only put 1 run into each room instead of two. As I wanted to do more than just ethernet into each room (can run phone, video, audio as well) I was forced to wire two sockets onto each run.

It's important to know which wiring standard your sockets use - 568A or B. B seems more prevalent, and is what I have here. It will be printed on the sockets themselves somewhere.

A useful summary of cat5 colour wiring standards, and plug and socket connections, can be found here.

Having checked that my sockets are 568B, I know then that wiring up the orange/white-orange and green/white-green pairs (on the back of the socket) actually corresponds to pins 1 2 3 and 6 - just what I want for ethernet. So, one socket has the orange pair and green pair wired to the corresponding terminals. The other socket on the same run has the blue and brown pairs wired to the orange and green terminals.

Note: once you've figured which wiring colour scheme your sockets are, stick to it like glue.

This is what it looks like:-

Note: a *proper* punch-down tool is a godsend for this stuff - don't even think of using one of the nasty little plastic ice cream spoon jobs.

Alternatively, as has been suggested, you can fully wire just one socket on each end of the cable and use doublers to split the pairs as I have done manually:-


So now, ethernet works in either socket, and as long as I use pins 1 2 3 and 6, I can also run phone or audio/video over either socket. Technically, I think I could run two phone lines - one on each spare pair.

My lounge and office currently have ethernet run to them from my (gulp) machine room via a switch under the stairs where the cable runs terminate. The other socket in the lounge has stereo audio and video run up it, through the patch panel, and out again into the kitchen.

PS. Switches. Belkin and PC World in good value shocker. 35 quid buys you an 8 port 10/100 switch with auto uplink detection on all ports. Bloody bargain!

>> Edited by Marshy on Thursday 18th December 16:53

>> Edited by Marshy on Thursday 18th December 16:56

malman

2,258 posts

270 months

Friday 19th December 2003
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Well done Marshy. A much better explanation than I could be arsed to put

Julian64

14,317 posts

265 months

Friday 19th December 2003
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Just a point that I'm not sure thats true. I believe that 10Mhz cards use only four of the eight wires but 100MHZ uses all eight.

I would check this before you chop.

Marshy

2,750 posts

295 months

Friday 19th December 2003
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Julian64 said:
Just a point that I'm not sure thats true. I believe that 10Mhz cards use only four of the eight wires but 100MHZ uses all eight.


a) It's 10Mbit/s and 100Mbit/s - not MHz.

b) Er, no, anyway. See the above diagram? That's my 100Mbit/s ethernet network, that is.

100Mbit/s and 10Mbit/s ethernet use the same wires. The only important thing to bear in mind is to keep the pairs twisted right up until the point you crimp connectors: not doing to is said to impair performance.

suffolkfox

458 posts

264 months

Friday 19th December 2003
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Technically speaking :sadgitmodeon:If you are using 100Base-T4 standards - that is you want to use cat 3, 4 or 5 cables ALL 4 PAIRS (8 wires) ARE REQUIRED. If you are using 100Base-TX (category 5 or 5e cables only) or 10Base-T the wires numbered 4 and 5 (one pair) and 7 and 8 (another pair)are unused and can be used to run the other lan line :sadgitmodeoff:

However, I recently changed my office router from ISDN to Broadband and found it did not work on one cable run. It turned out, after much testing, that there was a break in one of the lines that was not used by the 10baseT system in the ISDN used, but is needed for the new router and it's new 100baseT. Apparently there is nothing to stop router, etc, manufacturers using the spare line for other signal carrying, which according to my manual is the case with the router I have. Check before you waste time.

Marshy

2,750 posts

295 months

Friday 19th December 2003
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I've not met a 100Mb switch that wasn't 100BaseTX - i.e. eletrically compatible with 10Mb. This is also bourne out by the fact that I've never not had a crossover cable (that relies on only two pairs of four being wired correctly) not work in any router, switch or hub, ever. I dunno what router you've got, but it's certainly odd by modern (or even relatively modern) standards.

Let's be careful on the numbering front too: ethernet uses pins1, 2, 3 and 6 of the RJ45 plug, corresponding to pairs 1 and 3, orange and green, under the 568B wiring scheme. Edit: D'oh - misread the post - the unused pairs listed are indeed correct. Don't drink and post, folks.


>> Edited by Marshy on Friday 19th December 23:43

>> Edited by Marshy on Saturday 20th December 00:41