Here's how facebook does it: http://chunk.io/f/72f9c680ac2a4777b6dbf33c532e1d3c.jpg http://chunk.io/f/72f9c680ac2a4777b6dbf33c532e1d3c.jpg (Alec Moffat talking

Here's how facebook does it: http://chunk.io/f/72f9c680ac2a4777b6dbf33c532e1d3c.jpg http://chunk.io/f/72f9c680ac2a4777b6dbf33c532e1d3c.jpg (Alec Moffat talking at RealWorldCrypto) Seems like the combination of strong hash + encryption on a HSM is the way to go these days. Dropbox's scheme looks good to me.