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On Networking Two (Or More) Houses?
An Anonymous Coward offered this curious query: "A friend of mine lives four houses down from me. Of course, we're both flaming geeks, and have gotten it into our heads to network our computers over this distance. We've tossed around a few ideas, such as a few of the available wireless kits, or stringing up Cat-5 along with the phone lines. The problem is, we haven't found anything that can send a signal far enough, or else the process of connecting our houses together with wire would surely leave us electrocuted, and in jail. Anyone know of something that might work?" Interesting thought. Shaking my Magic 8-ball for an answer, it responds: "Possible, but solution may be expensive."
Betwen these two houses do you have line of Sight? If you do, there are some fairly inexpensive ways to go about it.
Directional Antenas on an Airport (apple). The base stations are about $299 (US), and can be configured using avalible software to work with x86.
There are many other ways...but that is the first one that pops into mind. I recall a story on slashdot about a DIYS microwave link ( link here )
If you just want to bridge one network to the other, perhaps a card and a ethernet bridge is your solution.
The PlayaNet project has some good pointers on 802.11 hardware, including antennas, even though their focus is Burning Man and not your residential neighborhood...
I think you should increase your budget. Consider the real cost. Budgeting $500 for a cable modem will last you what? About a year. The same monthly amount for not much longer will bring your budget up to $700, which is more reasonable for what you want to do. Then after that period, your cable modem is suffering from low bandwidth, and you still have those monthly payments. But the wireless is done and payed for, and you don't have to share your bandwidth with anyone.
Technical-wise, a pair of parabolic antennas and high-power base units should cover it. Forget those consumer grade units that whimper at well under 1W. IIRC, the legal limit is 3W and there are units out there that will pump out the power to drive 1km without a license.
For the original poster's situation. Four houses is nothing. (Unless you live in some place like Montana where four houses over is the next county.) If he's got line of sight, he could pick up a pair of yagis and any ol' base station will do. Probably won't even need to worry about interference from other signals. (If you're going over a few hundred meters, you should ask around if anyone else has a link up.)
Any sufficiently advanced civilization is indistinguishable from Gods.
Ethernet over Fiber.
That is, either 10baseFL or 100BaseFX.
You can pick up 10baseFL PCI ethernet cards for around $150 each, and 100BaseFX cards run $250 or so. The biggest expense will be the fiber itself, which could be $200-300 or so for a 100m run. Get the PVC covering since you're going to be running it outside.
You can get up to 1km or more over single-mode fiber.
If you're going hub-to-hub, use an AUI->10BaseFL tranceiver on each end (making sure each hub has an AUI connector). Don't use Media Converters - they suck and drop packets all over the place.
Realistically, fiber is probably too expensive for you. But it's so neat. :-)
And, of course, fiber doesn't have those nasty problems with weather interfering with microwave/infrared transmissions. Though you do have to worry about the birds sitting on the cable...
-Erik
There are always four sides to every story: your side, their side, the truth, and what really happened.
10base2 cards are just about free. I haven't priced cable, but it should be cheap at a commercial cable store (not Radio Shack/Home Depot/...).
Multiplexing is well supported for just about any device for kernel 2.4.0test4.
The problem with cat-5 is that it's not as resistant to weather and trauma as coax. That may or may not be an issue, though running multiple cat-5 and multiplexing them might be a better choice.
A firewall can not protect you from yourself. Turn off what you do not need. Do not use the firewall to do your work.
Putting copper on poles is a horrible idea. Sticking it in the ground isn't much better. One lightening strike and you've fried both ends of the connection.
My company built its new office building right next to the old one. For several months, we were working out of both. As such, we had to drag the phones and network between buildings. Initially, we were going to pull a 600-pair cable between the building for the phones. (A big fsking cable, by the way.)
After a couple hours of talking it over and hearing horror stories from our telecom guy, we went with fiber at nearly double the cost. Living in Florida, the lightening capitol of the world, it made sense.
If it were me, I'd go wireless. Using 3COM AirConnect, you can get 11mbps at 300 feet and less at more. With fancy ears, you can get even more range.
Of course, if you don't go wireless, think about fiber in the groud encased in interduct. That will be more expensive but is far better than copper.
Your best bet may be generic ADSL with a VPN though I doubt that would be nearly as satisfying to your geek urges.
InitZero
IIRC, there was an article right here on /. about a 2.4GHz wireless DIY project a while ago... or maybe that was kuro5hin...
/. (not the one I was looking for, but oh well...) about boosting Apple's AirPort to give better range.
/. earlier this year. This guy knows what he's doing, and it's not too expensive either.
Anyway, if you have line-of-sight between the two houses, I'd go for wireless (preferably RF/microwave rather than 802.11 or other shorter-range types). Here's a list of links that you might want to take a look at:
Wireless Projects, Vendors, and Products: Big collection of links on all sorts of wireless networking. If you can't find something here, give up.
This is a general outline of wireless LAN.
Ah, here's a bit from
..Ah, here we are - the DIY 10Mbit/s microwave project that was linked from
Hope these help...
First, measure the distance accurately. 10baseT has a 100m (328 ft) nominal distance limit. In the city, that would span 4 houses easily. Are you in the 'burbs? You could try pushing it a little if you use good-quality solid conductor cable. If you only need 2x, and can bury pipes, you could run 120VAC to the middle of the run and install a hub as a repeaer.
10base2 (thin-net, cheapernet) is readily available and has a 185m distance limit. (Note that even point-to-point, you MUST use a T-connector and a terminator at each end, unless you get a hub with built-in termination.) Again, repeaters are possible, although they're getting hard to find at good (mass-market) prices these days. 10base5 (old-fashioned thicknet) goes 500m. It's a pain to work with, and you need a good electronics junk shop to find the components cheap, but if you can find a long enough piece of the appropriate coax, you'll be cruising.
If you can't find 10base5 cheap (any high-tech companies that have been around for a long time might have a pile of components in a back room somewhere), then fiber is the cable of preference.
See what you can find, then ask a networking Old Hand how much you can push the specs. You can probably manage some. With low-loss well-shielded coax you can probably push 10base2 close to the 10base5 spec, since you don't have a bunch of intermediate nodes on the cable messing things up - it's just one straight clean cable. (Obviously, avoid kinks in the cable, get the connectors on the ends really well, and so on.)
Another alternative is to use a couple of DSL modems. That can go a heck of a long way over twisted pair. Although it's not as fast as ethernet or even some wireless solutions, they are getting pretty cheap. You can sometimes get them discounted from folks who want to sell you DSL service.
Running power and communication wires in the same conduit is in violation of the National Electrical Code, which probably means that it's in violation of your local building codes and almost surely will void your homeowners insurance.
As someone else suggested about a month or two ago in another Slashdot thread, check with your local phone company about the availability of "dry" loops--like a second phone line for each house, but wired directly to each other at the phone company and not connected to the phone system at all.
I see even classic Slashdot is now pretty much unusable on dial up anymore.
If you have cable TV in common, the arcnet cards work great and you won't even need to run the wires.
The real problem people keep talking about here under the guise of lighting protection is different grounds. In the US, they typicaly put a few houses on each transfomer and if your not on the same one, you will get some serious current flows on the ground of whatever cable you use.
That ground link should set off your ground fault circut break (if you have one). You can get some isolation by using cheap hubs that have one of thosue cheap wall pack transfomers. If your brave you can test it by floating its ground up. Plug in just the hub (not the computer) and connect the metal ground to the hot lead of the 110AC (its the smaller blade on the left). You will either fry the thing completely (while testing your circut breaker) or find out the thing doesn't use an exteranl ground or you'll fry your self. Either way it can be fun.
Once you've got your network hardware floating relative to ground, then you might want to pick up an isolating transfomer. These things are 110V in and 110V out but are isolated to keep service guys from frying themselves while working on TV's and power supplys. Once you have that, you will want to run about a 10K resistor between its isolated ground and your local ground. 10K will keep stuff from floating too much but limit the current should there be a problem. Measure it with a volt meter to be sure.
Pull the plug when there is thunder nearby. Thuderstomrs can induce large impulse currents in wires along the ground.
Other than tring to keep everything floating, you can also try using simple ballins. These are like the 300Ohm to 75Ohm adapters for TV's. They are just a simple transfomer and you used to be able to get them for 10baseT.
How much speed do you really need? If its available in your area, spend $40/month each for a cable modem or ADSL line and setup a VPN between the two of you. It still works great for games, and sharing files. Probably your cheapest short term solution.
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