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Nowadays, I usually make EIA/TIA-568A crossover cables for Fast Ethernet(10/100 Mbps) networks. On these cables, just 2 of the 4 wire pairs are used to comunications(the 2 remaining could be used for PoE or just for nothing), so I just needed to cross 2 color pairs(1-2 and 3-6 wires). However, on Gigabit Ethernet all the 4 wire pairs are used to increase the network bandwidth. So, to do a crossover on a Gigabit Ethernet I would need to cross all the 4 pairs. Is this feasible and reliable? I mean, how to make that and what is the correct color order of both ends of a Gigabit Ethernet crossover cable?

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3  
nowadays there is no need for such cables. You can use standard cable which supports 1Gbit (5E and upper) – bakytn Apr 9 '12 at 19:18
    
Just to be sure, you are running 1000BASE-T ? That's about 98% of hardware, but if you happen to be linking 1000BASE-TX the cross-over is the same as 100BASE-TX. – OCDtech Jan 14 '13 at 23:03
up vote 12 down vote accepted

Wikipedia has pinouts for a gigabit crossover cable.

Note that while Auto-MDIX is an optional feature of the gigabit ethernet specification (IEEE 802.3-2008: "Implementation of an automatic MDI/MDI-X configuration is optional for 1000BASE-T devices"), most gigabit ethernet interfaces do implement it, so in most cases you will not need a special crossover cable.

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same as 100BASE-T – OCDtech Jan 14 '13 at 23:04
    
it was my understanding that gigabit crossover is DIFFERENT from 100M and all 8 wires are a lot more twisted, and I remember that from a CISCO class I took years ago (and didn't used after ... always used a switch ... until now), also, I tested "normal" twisted (your webpage), even if network card report 1G connected, speed doesn't match up (I test transfer by moving data between ... ramdrives, on both computers just to be sure is not the speed of hard disk or something), and if I put a switch and non-crossover cables, then speed matches up – THESorcerer Jan 14 at 13:48

You don't: Auto MDI-X is built into the Gigabit Ethernet spec. The endpoints will auto-negotiate and take care of those communication issues.

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So the endpoints will always take care of it by default? – Diogo Apr 9 '12 at 18:44

For gigabit this is the pin layout you want to follow

PIN 1 - PIN 3 PIN 2 - PIN 6 PIN 3 - PIN 1 PIN 6 - PIN 2

So far this is a regular crossover cable. for gigabit use

PIN 4 - PIN 7 PIN 5 - PIN 8 PIN 7 - PIN 4 PIN 8 - PIN 5

For a color graphic guide follow the link below, is basically

ORANGE/WHITE ORANGE GREEN/WHITE BROWN/WHITE BROWN GREEN BLUE BLUE/WHITE

enter image description here

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