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[Gaffers]

In preparation of my upcoming trip away I have been tasked by somebody senior to me with setting up a LAN over which we could share evident and most films from either an external drive or a NAT.  When I was asked this I was going to be co located with them and I would look after the switch and drive.  Now I have been moved to a location several hundred meters away and the hard wired option is out of the question due to distance.  What other solutions can the geeks on here suggest that would enable me to connect with the other, say a dozen or so, users over a larger than normal distance where I am.the server.  I have to the server because they will break it if let loose on it.

Note also this is in a difficult terrain with daytime temps exceeding 45c, windy and dusty.

[Rods2]

Certainly not a directional Wifi link as it is not secure enough.

My suggestion would be an Ethernet to fibre converter at each end with an optical cable in between. A normal Ethernet cable has a maximum distance of 100m and emf radiation is readable, where fibre is not.

[Martian]

Certainly not a directional Wifi link as it is not secure enough.

WPA2 isn't being broken in any reasonable time frame, and there are plenty of other ways to add extra encryption on top.


@ Matt,

A couple of 24dB hi gain antennas each coupled to a 1W power amp will do it.

[Kevin Wood]

Does it have internet connectivity? The obvious solution if you have internet connectivity at both locations is a VPN connection.

Ahh.. Hang on.. read the rest of the question.

I would go with Martian's suggestion of hacking a couple of wireless LAN routers. Not strictly legal to put non-standard antennas on or up the power, of course, but I'm guessing that's not going to be much of a problem in this scenario.

There are doubtless other solutions, but I can't think of anything better that wouldn't up the price by a couple of orders of magnitude.

Do you have line of sight between the two ends of the link?

[cem_devecioglu]

fibre optics is the safest and fastest of options but with a high price tag..

[Gaffers]

It doesnt need to be secure as it's for personal use only.  Fibre would work great form a speed perspective but in the harsh conditions I fear it would degrade fast.

It wont be an official network as it is private thus I wont be able to lay official ducting or the like.  I hadn't thought about long range WiFi, would it be fast enough over say 500m?

[aaronjb]

Depends what you're trying to stream Standard definition video & audio? No problem, I'd say..

HD full bitrate stuff will struggle - heck, it can struggle on an 802.11n domestic link with good signal.

[Martian]

I hadn't thought about long range WiFi, would it be fast enough over say 500m?

What do you consider "fast"?

[Kevin Wood]

I hadn't thought about long range WiFi, would it be fast enough over say 500m?

The performance of a Wi-Fi network depends almost entirely on the radio environment where it's used. If it's the only wireless LAN user of the 2.4GHz band on site and there is a clear line of sight path between the two stations it should work OK. As soon as you start adding more networks it will degrade.

It's also worth bearing in mind the Wi-Fi was never designed to work over long distances so it will be susceptible to multipath interference in a built up area with buildings, vehicles moving around, etc.

Whether it'll be usable for your application depends on the application itself and the environment you find yourself in, some of which is going to be difficult to answer right now, I guess. I would say it's worth a punt, though.

Why not get a couple of old access points and a pair of yagi antennas and try a mock-up locally to see if it is likely to be a winner?

[cem_devecioglu]

I hadn't thought about long range WiFi, would it be fast enough over say 500m?

The performance of a Wi-Fi network depends almost entirely on the radio environment where it's used. If it's the only wireless LAN user of the 2.4GHz band on site and there is a clear line of sight path between the two stations it should work OK. As soon as you start adding more networks it will degrade.

It's also worth bearing in mind the Wi-Fi was never designed to work over long distances so it will be susceptible to multipath interference in a built up area with buildings, vehicles moving around, etc.

Whether it'll be usable for your application depends on the application itself and the environment you find yourself in, some of which is going to be difficult to answer right now, I guess. I would say it's worth a punt, though.

Why not get a couple of old access points and a pair of yagi antennas and try a mock-up locally to see if it is likely to be a winner?

yes and yes and yes..

similiar transmitters in the area will son create noise and problem.. you will have to increase signal strength.. but you may soon  face other problems..

[Gaffers]

but you may soon  face other problems..

Yes like getting caught 

[TheBoy]

My bro uses a Wifi link to link his shops about 200m apart. Rock solid 54Mbps (old kit, 54Mb is the highest it goes), bumpth reckons it will still manage 1Mb at 16km, line of sight of course. It was less successful when on tall poles, due to the narrow beam falling off line on breezy days.

So Wifi with the right antennas and the right Access Points (they need to be able to provide the power to the antennas) can cover usable distances.  But Wifi is inherently insecure, so cannot connect to 'official' lan segments

[CaptainZok]

Speckled Jim not good enough for you nowadays eh?

[aaronjb]

Certainly not a directional Wifi link as it is not secure enough.

WPA2 isn't being broken in any reasonable time frame, and there are plenty of other ways to add extra encryption on top.

That depends what you consider 'broken', because it's entirely exploitable - though you have to be authenticated to the AP already in order to futz with other people's (encrypted) traffic: http://www.darknet.org.uk/2010/07/wpa2-vulnerability-discovered-hole-196-a-flaw-in-gtk-group-temporal-key/

So not quite like WEP which can be opened up quickly without needing valid credentials - I'm sure that's what you meant but I thought if you haven't read about this it might make an interesting read If you have .. ignore me 

[feeutfo]

Speckled Jim not good enough for you nowadays eh?

Yes how is speckled Jim? Haven't seen him for a while, is he back from the front line yet? Hmm?