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Controlling Access to Wireless APs?
pvera asks: "A friend-of-a-friend-of-a-friend is thinking of offering wireless internet access at the medical conferences that he organizes. He already has people that can help him setting the access point itself and the connection to the internet, but he does not know how to control access. I am a T-mobile hot-spot subscriber, and my service uses some sort of proxy that does not allow me to surf thru their network unless I authenticate on a page that comes up regardless of what my home page is set to. Once I am authenticated then the proxy is transparent to me.
Here in Arlington, VA there is a company called iSurf networks that has the exact same setup as T-mobile, only they sell their service thru pre-paid cards. The cards are just like phone cards, your scratch a strip in the back to have access to the account id and the password. While you use the connection it shows a pop-up with a count-down display so you know how much time is left in your card. Does anyone know of a commercial or open source product that allows this functionality? Or of a company that provides an outsourced solution to do this?"
The IETF has been providing wireless service to conference participants for years now, wide open, you can use a key if you want to, but most people don't.
I have mod points and I am not afraid to use them
There's a funny story that's completely unrelated to but vaguely reminiscent of this. (Let's let the "off-topic" and "interesting" mods fight it out.)
WFAA-TV in Dallas, TX, was one of the first TV stations in the country, if not the first, to turn on its HDTV transmitter. It did this back in 1998.
Dallas is also the home of Parkland Memorial Hospital, a giant hospital complex. Some of you may remember Parkland as the hospital where President Kennedy was pronounced after his assassination in 1963.
Parkland Hospital has a giant cardiac ICU, as one would expect of a giant hospital. In the cardiac ICU they use wireless telemetry systems to monitor patients' hearts. Instead of having a 12-lead EKG monitor by each patient's bed and sending nurses around to check them, they put the leads on each patient and then connect them to a little battery-powered wireless transmitter. The transmitter sends the signals back to the nurse's station where they can be observed by a human being more conveniently and safely.
So back in 1998, WFAA flipped the switch to turn on their HDTV transmitter. And every single wireless cardiac monitor in Parkland went bat-shit.
The long story made short, as it was explained to me, is that the company that made the wireless monitors was, either through negligence or some kind of honest mistake, using the wrong frequency. The frequency they were using was allocated by the FCC for digital television broadcasts. This wasn't a problem at the time, because there were no digital television broadcasts anywhere in the country. Until that day when WFAA turned on their transmitter.
Ever since hearing that story, I've been a little skeptical about the much-lauded wireless revolution. Imagine if you will that the FCC, some years from now, reallocates the 2.4 GHz band for some other use. All the gear that currently uses that band, from microwave ovens to cordless phones to Bluetooth gadgets to your laptop, these things aren't just going to disappear.
Oh, trouble's a'brewin'.
I write in my journal
The long story made short, as it was explained to me, is that the company that made the wireless monitors was, either through negligence or some kind of honest mistake, using the wrong frequency.
I suspect they weren't really using the wrong frequency, per-se, rather, their frequency was a harmonic of the HDTV signal, or vice-versa.
In keeping with the best practices of the regulatory state, some genius decided that Medical Devices are exempt from RF shielding requirements. And every radio geek knows that every transmitter also an antenna. So, you take a medical wireless radio transmitter, don't sheild the thing, then turn on a honkin' transmitter nearby, and everybody is surprised when things stop working. <whine>But it's FDA approved!</whine>
On the bright side, when cell phones first started becoming popular, the hospital where I worked did an audit. Net-net: don't get within 4 feet of a respirator when you're broadcasting, but everything else is pretty much OK.
My God, it's Full of Source!
OUTSIDE_IP=$(dig +short my.ip @outsideip.net)