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Are Cat5e fully compatible with GBabit specification? What the main difference between Cat6?

Would like a proof if possible.

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up vote 2 down vote accepted

The main different between each version of the Cat specification is the numbers of twists per length of the cable.

Two wires running in parallel will create cross-talk. That is, if a current is running down one of the wires, the parallel wire will generate a current as well directly proportional to the distance between the wires and the current running in the wire. This is how a transformer works.

Twisting the wires interrupts this cross-talk, resulting in a cleaner signal as current running in one wire producese less of a current in the other wires. As signal speeds increase, the importance of cross-talk-free wires becomes more and more important and thus the twisting requirements become more and more stringent.

Cat6 has more dense twisting of the wires so that it produces a cleaner signal on each individual wire and thus will produce fewer errors allowing for higher communication speeds than Cat5e, Cat5, or any lower numbered Cat specification.

Technically, Cat5 can support Gigabit communication, but the primary factors would be the length of the cable involved and the environment the cable is running through. You may only get a Gigabit signal over a few feet of Cat5 or Cat5e while using Cat6 would allow you to send a solid and reliable Gigabit connection over dozens of feet without issue.

UPDATE for OP additional question: You are always playing odds with any situation like this. If you have low quality Cat5e, and/or low quality networking components, and/or your network cords run parallel to power conduit or telephone you'll find you have much, much less than 100m before you'll have difficulty running Gigabit over Cat5e.

Using Cat6, which was desiged for Gigabit, is much less likely to experience significant signal degredation when faced with similar problems.

Because there are so many factors you must take into account, there is simply no way for us to tell you "Cat5e will always allow stable and fast Gigabit connections if the run is less than x feet". And so we play odds. And so I will state that the odds are that, if you're dealing with lines parallelling power conduit or phone, if you're dealing with runs longer than several feet, and if you're dealing with consumer-grade components that will be connecting over these lines, you will not experience a speedy and stable Gigabit connection between all your components. It's possible you will have a perfectly OK connection. I just think there is a signficant likelihood that you won't unless you use Cat6.

However, since you've already run the cable, there's really no sense in tearing it all out unless after you've tested the lines and found whether or not their performance meets your needs.

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But for an house of 3 floors is Cat5e in walls enough to do a Gigabit ? That involve probably only 15 feets (A to B) – Rushino Oct 12 '11 at 17:06
If you're running new cable in a house, I would personally install Cat6. It will work better, give you more trouble-free communication, and the price difference is not significant. While Cat5e may work, there will still be a higher failure rate for individual packets and thus, while the devices may be able to connect at gigabit speeds, it will be a slow gigabit, not a fast one. – music2myear Oct 12 '11 at 17:18
Also Cat6 is much more futureproofed than cat5e. Unless you plan on changing the cables, use cat6. – Rob Oct 12 '11 at 17:46
They already got installed in wall. Its a bit too late lol that why i asked this question. This is something i would never think about.. – Rushino Oct 12 '11 at 17:48
@music2myear that not what im reading around the web. It seem it would be a fast gigabit if its less than 100meters. From what i know.. an house doesnt have for 100meters of cables.. in a business i would agree but not in an house.. you even said that the primary factor involved. – Rushino Oct 12 '11 at 17:57

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