Twisted cable???

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I bought two 10/100 network cards and in stalled them both in two computer. Someone told me i could connect them with out a hub bye a thing called twisted cable. I have a thousand feet of 8 wire ethernet cable and im wondering how i can do the twisted thing so i can network my comps without a hub. What lines do i need to cross? Or do i have to go buy a certain kind of cable? thanx for any reply's. = )
 

hypnotic_kumquat

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Dec 31, 2007
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What you meant to say was <b>"crossover"</b> cable. It basically switches (or crosses over) the send and receive lines.

Here are the pair orientations:
1 <-> 3
2 <-> 6
3 <-> 1
4 <-> 8
5 <-> 7
6 <-> 2
7 <-> 5
8 <-> 4

Or, if you like it all pretty using a common color scheme:

END1-----------> END2
Orange/Wh------> Green/Wh
Orange---------> Green
Green/Wh-------> Orange/Wh
Blue-----------> Brown
Blue/Wh--------> Brown/Wh
Green----------> Orange
Brown/Wh-------> Blue/Wh
Brown----------> Blue

-hyp
 
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Here's a link (with pictures) on making a cross-over cable using RJ-45 connectors. You'll have to buy at least a crimping tool.

<A HREF="http://www.littlewhitedog.com/reviews_other_00009.asp" target="_new">http://www.littlewhitedog.com/reviews_other_00009.asp</A>

Mike
 
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Important! Make sure that cable you make is more than 2.5 meters (about 8 feet) in length. According to the IEE 802.3 spec this is the correct length of a crossover cable to avoid signals bleeding thru from the XMIT or RECV pairs...
 
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I don't know if that's true (the 2.5 m thing). Look at patch cords for patch panels... They're only about 1-2' (30-60 cm).
 
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With regards to randair and God TM I think you may both be incorrect. Crossover cabling is not even discussed in the 802.3 (ethernet) spec except to mention that such wiring is beyond the scope of the 802.3 spec. Logically, I dont think that the length of a crossover cable segment should be any different from normal straight through UTP since the only difference is at the termination ends and thus any additional signal degradation caused by the crossover termination would be the same regardless of the cable's length. FYI the 802.3 spec recommends that a cable segment not exceed 90 metres in length. Also, I am using a 50' crossover UTP cable with no problems or noticable loss of speed.
THanks
 
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Rather than making your own (and avoiding the whole minimum cable length argument and the errors you WILL make if you are not accustomed to making cables)

Go buy one.

RadioScrap and Compusa both have those types of cables available. Believe it or not, the one at compusa SAYS its a "Gaming" cable... lol

And as far as the cable length thing - use long ones! You will undoubtedly need the extra length one day and making a dinky one is just silly. :lol:
 

hypnotic_kumquat

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Flamehead's right. Normal length limitations apply. BTW - Cisco even ships a 39" crossover cable with their routers. I've used those between PC's without any problems.
 

lasse

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I do frequently use very short twisted-crossover cables between my notebook and other computers. So far without any problem.

About cable lenght. Short networks sometimes causes problem.
It's more of a problem with ThinEthernet (Coax) where you should not end your network at your computers T-connector but rather have a meter or two, beyound the T-connector, and there terminate it at each end of the network. This is important if your down to network lenghts below 20 meters/yards. It will work, but sometimes slow.