Question Ethernet cable long run - realistic max?

siltsunrise

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Sep 2, 2015
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I'm sick unto death of seeing everyone say 100 meters. Like at 101 meters, it won't work anymore. Like the glue has to dry for exactly 24 hours. **, and relatively meaningless figures.
Can someone with actual experience tell me how long you've run some cable and had it work ok? I am looking at a 200 meter run or longer and wonder if it will work at all. It doesn't have to be perfect, just work. I'm not a data hog.
Which CAT is known to support the longest run?
Cheers!
 
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100 meters is the safe answer.
depending on the equipment in use, the cable ends and the cable itself, more than 100 MAY not be possible at all.
with the right equipment (modded high xmit power) and cables 125 may be doable but the data packet loss will be bad. the 100M has more to do with ohms law than anything else. the cable itself resists the current over long hauls without something to amplify the fading signal it fades and quickly. the twists of the wire help to insulate against crosstalk and EM but resistance in the copper wire itself and the set voltage of the standard governing the network equipment is why 100M is the answer your getting.

https://en.wikipedia.org/wiki/Ohm's_law
 
Well explained above.

From what I have seen it seems to break at almost exactly 100 meters. Maybe you get 105 or something but generally nobody even tries it because the labor costs to run cable is better spent running fiber.

What you can do is use something that is not ethernet. They make ethernet "extenders" that can go many kilometers but the longer you go the slower it gets. You get nowhere near 1gbit. Most the devices I have seen use a form of DSL to accomplish this. So you have limitations similar to DSL but these can run on a single pair of phone wires. There are models that use other things like VDSL and other methods.

200 meters might be possible using other methods. They make switches that can be powered via PoE. You could put one of these at the mid point and get 200meters. This solves the power issue but these are not designed to be buried or put outdoors where it is wet.....there might be some models but you would have to search. Because of the limitation on PoE power you can only do this one time. Of course if you are in a building with power outlets every 100 meters there is no limitation really to how many switches you can have.