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Auto-Scanning the Names People Choose For Their Wireless APs
MichaelSmith writes "I code on the tram, going to and from work, and I noticed that there are a lot of WiFi access points along the way. So one week I made it my job to write an automatic scanner which runs from a cron job every minute during commuting times. My backup script pushes the new AP names to my web server and you can read it online. It is a mixture of the straightforward, naive and funny, with a few pop culture references along the way. The first column in the file is the number of access points with that name. The second column is the AP name, in brackets to pick up white space." Why can't "Dress Me Slowly" and "Domestic Bliss" just share an AP?
"dress me slowly" is a retro clothing store on Nicholson St in Fitzroy. The tram route is therefore route 96 in Melbourne Australia..
What? This wasn't one me those tram spotters quizzes?
Not only is it legal, but it's been going on for a long while now.
Oh, I definitely broadcast my SSID. I've run into the stomping into each other problem before. It's a pain to do a site survey of who's around, pick a channel, just to find out that there's other traffic interfering.
I know mine is receivable for a longer distance than others in the neighborhood. When they installed it, I wasn't here, and they put the AP under a desk, with a metal file cabinet beside it. {sigh}. I moved it up on top of the file cabinet, and that (amazingly enough) fixed a lot of my problems. I'd guess the neighbors got theirs installed somewhere, and they left it exactly where it was placed.
I've had to change my channel twice where I am now, because the defaults for whatever a neighbor installed were on my channel and ruined my throughput. I may look like a lunatic walking around the house with the laptop listening, but it tells me what channels are being used, and what are free. It's kinda funny, there are three near the house that are all on the same channel. I bet they wonder why their connection is terrible, but it's not mine to fix. That, and I'm not ambitious enough to go find their house and offer to fix it. I did that once in an office building. Someone turned on an AP and stomped on my traffic. I wandered around, found them, went to the receptionist for the company and asked to see whoever was in charge of IT. They were completely oblivious to what I was asking.
"Who takes care of problems with your computers?"
"I don't know"
"Can you please find someone who does know?"
"Why?"
"Because your access point is broadcasting over the legal limits for power, and is disrupting service for other occupants of the building."
"What's an access point?"
"It's the device that handles wireless network traffic."
"I don't think we're on a network."
"Can you go to web sites?"
"yes"
"Then you're on a network. Can you find the person who runs it"
"No one here knows." (without asking or even picking up the phone)
The conversation went on for a few more minutes, before I just gave up.
I didn't know positively that they were over the legal limits, but since I had a good signal from their office several floors below, and even a good distance from the building, I figured they were doing something they shouldn't be. At least when I've put high gain antennas on, I look around, make sure I won't interfere with anyone, and use a very narrow beam antenna (i.e., a good parabolic), that doesn't come close to any other buildings. When I went hunting for my own signal in that circumstance, I couldn't even pick it up at ground level standing under the receiving antenna, 20' below it. I've only done that on long point-to-point connections, not as a general AP in an office building.
Serious? Seriousness is well above my pay grade.
I see these "Free Public WiFi" ESSIDs all over the place in public areas, such as airports. They never work. They're usually ad-hoc networks.
I assumed for a while that they're symptoms/carriers of some kind of malware, but didn't really worry about it since I don't use Windows.
I just read this article which has a slightly crazy but just-maybe-plausible theory to explain them. They think that it's a weird, propagating out-of-control Windows XP feature, which makes every network to which an XP computer connects propagate its name as an ad-hoc network. And then when somebody else tries to connect because of the enticing name, they keep the ESSID alive for another minute since it's an ad-hoc network, and this continues ad infinitum. So the whole thing is nothing but a long-lasting "echo" of a forgotten network that keeps alive in heavily trafficked public areas. The whole idea seems nuts. Dumber than dumb. Dumber than Microsoft even.
But I haven't heard of any better explanation for the "Free Public Wifi" phenomenon. Anyone else???
My bicyles