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We have recently done a change in our network by using CAT 6 cabling. Now I would like to measure the speed difference when I use Cat 5 or Cat5 e and Cat 6. Is there a way to find out the same?

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just changing cables won't affect network speed. – Javier Feb 18 '11 at 14:06
If it does affect the network speed, then you had something seriously wrong in the old network. :-) – Brian Knoblauch Feb 18 '11 at 14:47

CAT5e is perfectly capable of supporting 1GB connectivity. Most do not realize that the issue is typically not in the transmission media, rather at the points where IO creates bottlenecks.

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If you have a file server that you know is not the bottle neck, simply transfer a big compressed file a few times and time it while there is not much other network activity.

In some cases Cat5 can work up to a gigabit, and if that was your case, you will probably not notice a huge difference.

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Are you running gigabit switches/network cards? If not, your not going to notice any difference. If you are, then depending on disc i/o, you should be able to transfer files quicker- test from server > server.

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Yes we are running gigabit switches. How do I measure the disc i/o to transfer the file from one server to another. I have one linux server and the other is a windows server. – user45774 Feb 22 '11 at 13:41

You can use 'netcat' on Linux to test pure network speed, without having to worry about approximations using file transfers (limited by disk IO).

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In this scenario, if you had Linux, would you use /dev/zero on the sender end and /dev/null on the receiving end? (or just nul on the recevier if it runs Windows) – jftuga Feb 18 '11 at 13:48
Correct. However, iperf is actually a better solution nowadays. (I forgot about this when replying!) – Craig Mason Feb 21 '11 at 10:54

The most limiting factor won't be the cabling - but disc-performance and the servers/clients and their configuration (+ switches/routers) matter.

The biggest impact on the "faster" cables will be fewer errors - at the same speed...


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