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Re: Throughput riddle

On 03/18/2016 06:47 PM, Richard Hector wrote:

On 19/03/16 14:01, David Christensen wrote:

I use category 5E cables for Gigabit.  Category 5 and category 6
cables were not reliable for me.


Cat 5 cables _should_ work, in theory, though I gather some don't work
so well. If you have any cat5 or better cables that are unreliable,
I'd suspect the individual cable, not the stated spec. They may just
be badly made.
Along with the tester, I also bought a 1,000 foot spool of category 5E riser cable, a crimping tool, and crimp connectors. Now I make my own cables and test them. :-) 



Perhaps the NAS has an automatic crossover feature on it's Gigabit
port. If you do a computer-cable-computer test, you will want a
(category 5E) crossover cable.


There's no need for crossover cables for gigabit. Gigabit communicates
both ways over all 4 pairs anyway, and autonegotiating is part of the
spec.


Thanks for the tip!  :-)

    https://en.wikipedia.org/wiki/Ethernet_crossover_cable



Make sure you are using the right cables and that they are known
good. I own an Ideal LinkMaster cable tester, and it has been worth
every penny:

http://www.amazon.com/Linkmaster-UTP-stp-Cable-Tester/dp/B000LDC3LA


A tester like that will tell you if there's continuity in the right
places - a cat 3 cable will test fine, and you could make a cable with
phone cable, power cable or whatever you like and get it to test fine.
Testing to Cat5 or whatever takes a _much_ more expensive tester, to
check impedance and capacitance (and variations of those down the
cable) and suchlike. It's a good start, but probably won't help much
for "it's a bit slow".
I've spoken to sound/ communications technicians who talked about validating Ethernet cabling to X MHz and I've glanced at the expensive Fluke networking meters that I assume can do such measurements. Fortunately, a simple continuity tester and whatever utilities the OS provides have been enough to get me by. 


David
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