LITTLE BROTHER INSIDE

[hughes@ah.com (Eric Hughes)]

   Prior to seizure/theft, you would make an 
   arrangement with an offshore "escrow agent."  After seizure you would 
   send your computer the instruction that says, "encrypt my disk with the 
   escrow agents public key."

You don't even need public key.  Just place a secret key in the hands
of your if-duress-no-release agent and put the same key in the right
place in nonvolatile, but erasable, storage inside the computer.  In a
standard PC, there's room for this in the battery-backed configuration
RAM, which has lots of extra space on many newer models.

The use of public key would still require that a session key for a
(fast) symmetric cipher be generated and then destroyed, so you're not
that much better off.  The advantage is that you don't have to destroy
the public key.  Since destruction is pretty easy for information, I
don't consider it much of an advantage.

And, lastly, if you were to use public key, you'd want the agent to
generate a key pair for your use only.  This avoids linkage with other
information.

Eric