Here is a video that explores the possibility of ‘Position Based Cryptography’ and the security protocols for two fundamental tasks: secure positioning and position based key exchange.  This video is delivered by Nishanth Chandran, from UCLA.

If you want to see a good use of that GPS system on your phone combined with cryptography, this is a great video.  If you are looking for funny videos about dogs, this is the wrong place.

You may need to refresh the video or use this link to go direct:

http://research.microsoft.com/apps/video/default.aspx?id=103344&s=0&e=2668

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