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Bought a spool of wire for networking. Ran it a long distance and thought we could hook up the wires to a plug at the end (not sure how to describe this).

However the spool of cord/wire we bought is only 6 wires while an ethernet plug is 8.

Can we only leave 2 out?


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If I recall correctly... Ethernet is a Transmission standard of some sort, not a cabling standard. – xenoterracide Nov 16 '09 at 2:21
up vote 15 down vote accepted

Networking wire isn't just any old spool of wire. It's rated for the frequencies of the signal going down it (CAT3 for regular phones or 10Mbs Ethernet; CAT5 for 100Mbs Ethernet; CAT5e, CAT6 for 1000Mbs Ethernet), there are pairs of wire twisted in certain ways to reduce the cross-talk between wires, there may be shielding to reduce noise from outside, etc.

It sounds like you're trying to run networking over a random spool of wire. Don't do that.

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See my comment above. It is networking wire after all. :) – bobber205 Nov 16 '09 at 1:51
Nope, Cat3 ain't networking wire. It's phone wire. You're gonna have trouble with it. – retracile Nov 16 '09 at 1:52
Damn. Thanks for letting us know. – bobber205 Nov 16 '09 at 1:54
Just as a note, CAT3 IS networking wire, but no one uses it for that anymore. 10mbps networks used to be run fairly commonly over CAT3 at Universities and such before LANs were more widespread to businesses and the like. At my old University admin job, we had a few buildings that still had some floors networked via CAT3 at 10mbps. – phoebus Nov 16 '09 at 2:17
phoebus: And then there was the COAX stuff ... ah, the memories. – retracile Nov 16 '09 at 2:27

10/100 will work with 2 pairs (4 wires). Faster requires 4 pairs (8 wires.) Power over Ethernet requires more than 2 pairs (usually.)

Note that if you have "6 wires" I'd be very certain it was CAT5.

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We just looked and it was Cat3 wire. xD – bobber205 Nov 16 '09 at 1:50
I don't even run cat3 for phones anymore. It's cheaper to just run cat and not worry about what goes into the socket. Well, now it's 5e/6 I suppose. – Michael Graff Nov 16 '09 at 2:08

Yes, you can make this cable work, but you are unlikely to get good performance, particularly if you try and run faster than 10Mbps. I would not use this cable if I could figure a way around it.

Basic Ethernet only requires 2 pair to function. You should map two of the pairs in this cable to the colors/pins needed for Ethernet transmit and receive (typically Orange and Green??) and terminate according to the instructions in whatever jacks you get. You can get jacks that don't require special tools to terminate (example) .. they should be fine for low speed applications.

The only other thing I would do is force the NICs and switch ports to 10Mbps in order to minimize problems.

REMINDER -- this is a last resort solution. If at all possible, get good CAT5e cable and have it installed by pros.

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We've decided to buy new wire (or have me to go the store next time xD ) – bobber205 Nov 16 '09 at 6:48

I am not a big fan of Yahoo answers, but it was quick and easy. HERE Be sure to do some Googling also and good luck.

EDIT - I would add that retracile us right, but if its rated for telephone it will prob work fine. I have run more CAT5 that I care to remember through ceilings, under floors...once under the concrete floor of a morgue that required crawling under a couple hundred yards of dark, spooky building. If I later discovered that it wasnt the correct wire, but I could make it work...I would have MADE it work.

Another EDIT:

1 white/green Transmit+... 2 green Transmit-... 3 white/orange Receive+... 4 blue Unused... 5 white/blue Unused... 6 orange Receive-.... 7 white/brown Unused... 8 brown Unused

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That's only correct for 10/100Mbps. – Brad Gilbert Nov 16 '09 at 16:28
thanks for the info BG...I was thinking it was totally doable if necessary, but have never personally tried it. I read an article on hackaday about using the other 2 wires for low-voltage power. – cop1152 Nov 16 '09 at 18:16

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