From: Jeremiah Blatz <jer+@andrew.cmu.edu>
Date: Mon, 30 Mar 1998 09:43:58 -0800 (PST)
To: coderpunks@toad.com
Subject: Re: Deniable Cryptography [was winnowing, chaffing etc]
In-Reply-To: <Pine.LNX.3.96.980328173343.23115B-100000@localhost>
Message-ID: <0p7xTq200YUg0CkXw0@andrew.cmu.edu>
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Content-Type: text/plain


mgraffam@mhv.net writes:
> -----BEGIN PGP SIGNED MESSAGE-----
> 
> On 28 Mar 1998, Julian Assange wrote:
> > Rubber-hose-squad: We will never be able to show that Alice has
> >                  revealed the last of her keys. Further, even if
> >                  Alice has co-operated fully and has revealed all of
> >                  her keys, she will not be able to prove it.
> >                  Therefor, we must assume that at every stage that
> >                  Alice has kept secret information from us, and
> >                  continue to beat her, even though she may have
> >                  revealed the last of her keys. But the whole time
> >                  we will feel uneasy about this because Alice may
> >                  have co-operated fully.
> 
> I've never really fully understood this assumption. It seems to me
> that any person or group that would beat a person isn't going to
> care much if Alice cooperated or not. 
> 
> All things considered, a group with enough power to grab Alice and
> beat her probably has ways to escape punishment from the law, or
> doesn't care about the law in the first place. 
> 
> In this case, I figure that their best option is to beat Alice everyday
> forever or until she dies. Whichever comes first.

"Rubber hose" cryptanalysis needn't involve actual beatings in secret
underground cells. Simple example: Cops raid your house, rough you up
a little bit (not much) and toss your ass in a cell with "real '
criminals. 12 hours later they take you into a room and play good
cop/bad cop with you. Maybe you're not sure you could stand up to
this, and might panic and reveal more than you have to (remember, you
haven't been charged with a crime yet). However, if you do hold out,
the chances that you'll be let go, and get your stuff back in a few
years, are pretty high. In this case, being able to spill a key that
revelas harmless stuff is good, since the police are unlekely to hold
you for a long time.

"Dissapearing" is the regressive case, and there's not a whole lot you
can do in regressive cases. If someone really wants to defect, they
will.

Jer

"standing on top of the world/ never knew how you never could/ never knew
 why you never could live/ innocent life that everyone did" -Wormhole