Authentication Via Geographical Location?

RudeDude asks: " While reading Cryptonomicon I became a bit paranoid about encryption and digital signatures but it has me thinking a bit as well. I'm trying to visualize a way to prove my physical location in a cryptographically strong way and I can't think of one. My digital signature proves who I am, but wouldn't it be nice if I could also give proof of my physical location at a given time stamp? I've thought of only a few things that would be very hardware dependent, etc. but what I really think would be cool would be something that is as strong as digital signatures. Some sort of GPS/MD5 signature that a third party could confirm so that it would be impossible to spoof my location. " This question has been asked a bit by people looking to restrict services to various countries, but currently one can't be sure if the IP a person is using is really the location from which the connection is being made. Would a system like the one described above be a possible answer?

"This is mostly just a thought experiment, but I am curious to see what other Slashdot readers could maybe dream up. In my opinion (and I'm sure many others as well) my current meatspace coordinates usually mean much less than my network 'location' does, but I can think of many times where proving my meatspace location could be just as important as proof of identity."

Comments

Fringe benefits for various internet sites

[Brento]

The internet gambling industry has been looking for something like this for quite a while. If people can prove they're inside physical areas that are allowed to gamble, suddenly internet gambling is wide open for companies like Harrah's and Caesar's to take on. Currently they can't do it for fear of being sued in areas where gambling is illegal.

The drawback: pr0n users in the bible belt would be suddenly unable to hit their favorite sites. Site operators would restrict content to areas where they could be certain of legalities.

And even worse, Amazon could now target prices based on the economy of your neighborhood.

A solution of sorts

[Peter Eckersley]

GPS isn't really enough. You need to have something which you couldn't have had if you were anywhere else. Satellites could give you this, but only if they beamed different, cryptographically secure, messages in different directions.

The simplest example would be an "authentication satellite", where Jane asks the satellite,

"is Bob really in France?"

...Satellite sends encrypted message for Bob in the direction of France...

If Bob knows the contents of the message, he's in France.

Of course, Bob could just have a tranceiver in France.... so.... quantum encrypt it in a single photon :). Single photon quantum encyption is nearly good enough for Earth-satellite links, IIRC.

None of this fixes the "problem" (is it really a bad thing?) mentioned elsewhere in this discussion, that physical devices and people are separable...

only on slashdot

[nomadic]

So we go from people complaining that new technology can be used to track them to complaining that new technology can't be used to track them.
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