Long distance network run

July 13, 2007 2:09 PM

How can I transmit a home network connection 600 feet across a forested piece of property? We have WildBlue with a Linksys router, and I'd like to access it from our guest cottage. I'm doubting we can run an Ethernet cable that far.
posted by hodyoaten to computers & internet (14 comments total)

I bet if you put the router on a window ledge and used DDWRT firmware on it, you could cover that distance without too much trouble. DDWRT allows you to crank up the transmitter power of the router.
posted by cosmicbandito at 2:17 PM on July 13, 2007

Maybe try a homemade directional antenna?
posted by demiurge at 2:22 PM on July 13, 2007

Cat-5 is rated for 100 m, half that distance. I really don't know how quickly performance drops off beyond that point, although I wouldn't be surprised if you got adequate performance over it.

The 802.11n (draft) wifi should cover that distance with no problem, I think.
posted by adamrice at 2:24 PM on July 13, 2007

Point two high-gain directional antenna at each other. Cheaper. Dirt cheap.

The real question will be figuring out if you really need two directional antennas or one direction with a line of sight to your linksys. Because its forested, you'll have to at least mount the directional above the trees. This is dangerous. You should hire a pro.

You can run ethernet for 300 feet. If you dig 8-12 inches underground you can pretty much bury it and forget about it. You can buy 328 feet of ethernet for under 50 dollars. Buy a switch and put it in the mid point (you'll need power of course). Run another 328 footer to your cabin. Doing this hillbilly style is most likely a fire hazard or a lightning attracter, so be warned.

Then there's fiber. Someone more experienced can comment on the difficultly and price of that.
posted by damn dirty ape at 2:24 PM on July 13, 2007

Is it line-of-sight? I'm remembering an open-source hardware project that used LED transmitter/receivers to share a network connection over a pretty significant distance. I can't seem to track it down right now, but I'm going to keep looking.
posted by god hates math at 2:26 PM on July 13, 2007

For 600 feet? You could probably just blast through the trees with a couple of 15dB antennas. You might need to bump the transmit power up to 100mw.
posted by wierdo at 2:31 PM on July 13, 2007

GHM, possibly thinking of Ronja.
posted by hattifattener at 2:34 PM on July 13, 2007

Yes, you're right - it was Ronja.
posted by god hates math at 2:39 PM on July 13, 2007

You might be able to do it with good ol' thin-net (10Mbs). This was a 50 ohm coax ethernet standard. It was a bit of a bear for real networks but for point-to-point it shouldn't be too bad. Max length for thinnet was 600 ft I think.

I'm having a hard time finding pics or anything useful other than nostalgia pages.
posted by chairface at 3:18 PM on July 13, 2007

thicknet coax will get you 500m.
posted by rhizome at 3:25 PM on July 13, 2007

Thinnet is good for 200m, by spec (actually a little less, somewhere around 185, IIRC), but you might be able to make it go farther since there wouldn't be any intermediate Ts.

Cat5 will also go significantly farther than spec, but fiber would be safer, faster, and more durable. Media converters can be had for a couple hundred bucks a pair. The problem would be the connector, but you could always bury some PVC and pull some pre-made fiber through.

Thinnet is easy to work with, and I'm sure you can still find the wire at any specialty distributor. Connectors shouldn't be too hard to source either, but I could probably come up with both wire and connectors in a pinch. We used to do a lot of thinnet. The hardest part is putting the connectors on, but it only takes 20 or 30 dollars worth of tools.

I wouldn't want to run copper between the two, though. Between the differing grounds and the lightning potential, it's a mess waiting to happen. We had problems with some thinnet installs indoors in old buildings that were poorly grounded. Network cards would blow every time a storm rolled through. It was a nightmare.
posted by wierdo at 3:43 PM on July 13, 2007

thicknet would be cool (god it's been so long!) but 10base5 (5 == 500m) wire I would imagine to be rather more costly than thinnet aka 10base2 (2 == 200m) as mentioned.

in both cases you should not have any trouble sourcing cheap pci cards and/or hubs.
posted by dorian at 4:39 PM on July 13, 2007

Similar questions have been asked here before: WiFi with my neighbor?, Will o' the WISP, and What kind of network cable to run underground?

Grounding is not an issue, ethernet devices are transformer isolated (self link). Lightning probably isn't a big deal either, as long as you can afford to replace the cable/hub/router/switch, if the worst happens.

If you read those old threads, you will see links to DIY power over ethernet solutions. With power over ethernet, you could put a repeater half way along. May not be the best choice, depending on your needs and preferences, but it is another choice.
posted by Chuckles at 10:37 PM on July 13, 2007

The answer you are seeking is wifi and directional antennas (and up the power) ... if you can get a adequate line of sight through the trees.

OR

A fiber run with media adaptors

OR

perhaps ethernet ... running full duplex between two switches ... may work ... however it is certainly not in spec ... Ethernets limitations on distance are intrinsically related to collisions and timing ... full duplex ethernet between 2 switches (or 1 end device) will not have any collisions so may just work! However I have never done it so I can't speak from personal experience.
posted by jannw at 9:30 AM on July 14, 2007