From: Adam Back <aba@dcs.ex.ac.uk>
Date: Mon, 23 Jun 1997 04:51:38 +0800
To: tcmay@got.net
Subject: Re: Laying PipeNet
In-Reply-To: <v03102802afd305494670@[207.167.93.63]>
Message-ID: <199706222045.VAA00836@server.test.net>
MIME-Version: 1.0
Content-Type: text/plain




Tim May <tcmay@got.net> writes:
> At 3:02 AM -0700 22/6/97, Adam Back wrote:
> >Text stego is hard to do.  At ultra low encoding rates (say a few bits
> >per email), it would be ok.  (Just message parity, perhaps the entropy
> >in the message-id, posting time).
> 
> Pointers can be useful. A small number of stego bits in a message of this
> length could be used to tell a recipient where to look for a longer
> message. Thus, this message could contain instructions to "Look at the
> image "cindy-fake17.gif" in "alt.binaries.erotica.cindy-crawford" for
> instructions about the Cabal meeting."

Provides some plausible deniability, more than posting random numbers.

> If the images are recyclings of older images, as most images in
> these porn groups are, then there is the problem that images may be
> diffed (compared) and the LSBs detected to be different. Fixes for
> this either include deliberate (and stated) "enhancement" in
> Photoshop, which is also fairly common, or scanning of some of those
> old Penthouse mags laying around! :-)

That's the major problem with images, you need to generate your own.
Unless you fancy writing an image enhancement system, and analyse the
algorithms in existing systems to ensure that randomness is
introduced.

Another idea, there's a golf-ball cam on top of my monitor, how many
list members have played with CU-SeeMe?  (You'd get to see my 2 year
old son playing with his toy tractor on the desk, making it difficult
to type, keeps pulling my hands off keyboard).

Does any of the CU-SeeMe stuff come with source code?  Cons: at 28.8k
modem speed, the image frame rate is poor, but worse the audio is near
unusable, also limited to 8 conference participants.

Or how about enhanced IRC with VR chat rooms?  You could get lower
bandwidth IRC stylised computer generated VR than you could video
stream.  I'm sure you could come up with some subliminal channels in
that (computer generated images, simulated moniker movements), and
you'd just need to chat on #cypherpunks for a while, and your posts
would be sent.  Quite plausible for cypherpunks to stop off at
#cypherpunks and reminisce about the days before non-gakked crypto was
outlawed.

Adam
-- 
Have *you* exported RSA today? --> http://www.dcs.ex.ac.uk/~aba/rsa/

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)]}\EsMsKsN0[lN*1lK[d2%Sa2/d0<X+d*lMLa^*lN%0]dsXx++lMlN/dsM0<J]dsJxp"|dc`