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I always thought that to connect two computers directly without using a hub or switch we needed an cross over ethernet cable, but this says that

If one of the two computers has a gigabit ethernet card, a crossover cable is not necessary and a regular ethernet cable should be enough

Why is this the case? Is there something in the Gigabit Lan specification that guarantees this and does this mean that for fairly new computers I no longer will need to specifically look for cross over cables in the market?

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Check out MDI/MXI capabilities and the requirements from gbit nics. – Hennes Dec 22 '12 at 19:13
up vote 4 down vote accepted

Yes, Auto MDI-X (invented and promoted to IEEE in 1998 by HP) is an optional part of the 802.3AB 1000BASE-T specification, that has been widely implemented. So, you may run into a 1000BASE-T NIC without it, but I doubt it highly in this day and age.

Keep in mind 1000BASE-T is not the only type of Gb networking, just the most common.

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