Calculating performance of outdoor wireless network links

Reading Time: 10 minutes

This article contains information on how to calculate the operating margin of a wireless 802.11 network using a known distance between the two points.

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I wrote this quite a while ago and although the throughput of wireless links has dramatically increased the basic theory still applies. Of course we now have 5GHz available, which is very useful for this application. You should be able to substitute ‘f’ for 5000MHz and the maths will still work.

You can now get a 150mbps PTP link over 15km using equipment that costs £160 for both ends – that’s the entire cost of the system (minus a couple of poles and brackets). Crazy value for money when you think about it. The Ubiquiti NSM5 NanoStation is one such example. The Ubiquiti product range is pretty impressive to say the least. The NSM5 seen below is the big brother of the LOCOM5, which at £125 can still do 10km at the same rate and are around half the size.

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If you are considering an outdoor wireless link, give this article a read so you understand how high above objects you need to mount your shiny new kit!

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Providing Free WiFi For Anyone To Use

Reading Time: 6 minutes

As the UK government have announced they wish to classify Internet access as a public utility (implying it shouldn’t be a privilege but should be more like electricity etc) I thought I’d share how I have opened my Internet connection for anyone to use. As long as you can receive the signal you can connect and browse to your heart’s content without any keys or passwords.

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Firstly, this is against the T&C’s of most ISPs, including mine. There’s a few (il)logical reasons for that but it’s mainly revenue protection. Even though they know a single connection would be perfectly suitable for many households to share, they would obviously lose money if everyone did that. Namely because, unlike other utilities, Internet access is generally not metered, meaning it’s a fixed cost per household per month. If your neighbour cannot afford their own Internet access or for whatever reason cannot get a contract then I feel it’s only fair to allow them to use mine. With talk of some people not being able to afford heating during the winter it’s hardly appropriate to expect them to also afford broadband. Who needs Internet access though? I mean it’s not like online shopping is generally cheaper or anything, not to mention almost everything is moving towards e-billing, right?

I’m not going to suggest everyone should just blindly open up their WiFi router for anyone to use but here’s how I’ve achieved this safely.

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How To: Read Your Neighbours Facebook Private Messages

Reading Time: 9 minutes

For a casual bit of weekend fun I thought I’d share a potential method for obtaining your neighbour’s Facebook password. This is purely educational and I used my own systems to do this but it highlights how potentially easy it can be to obtain someone’s login credentials to any website.

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We are going to utilise various attack vectors to demonstrate the methodology of the process. The story starts with a hypothetical situation.

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