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Just when I though I know everything about how computer works, here they are talking about freezing ram attack. I didn't even imagine this as a possibility.

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So, it's obviously hard to defend against a freeze attack when the computer is sleeping - because the key is still needed.

But I feel like disk encryption software should, when the computer is being shut down, prepare some random data and write over the encryption key to prevent information leakage in the moments after shutdown. This, combined with some hardware intrusion detection system would help a lot, wouldn't it? Or am I missing something?

There's a neat implementation of AES that uses only registers and never has the key in RAM after boot. I forget the name right now, but it's pretty fucking awesome. IIRC it puts the key into debug registers, then disables access to those registers. It calculates the key schedule on-the-fly for each block it encrypts, and it performs decently with AES-NI. So neither the key, nor any of intermediate pieces, are ever in RAM, just in registers.

Edit: Here it is: Tresor: http://www1.informatik.uni-erlangen.de/tresor

I assume the speed of SSD's would be a good counter here. Never sleep, only hibernate or shutdown.

This showed up in Burn Notice, though I can't remember the episode. It's cool to see it's real.

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