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/ print pack"C*",split/\D+/,`echo "16iII*o\U@{$/=$z;[(pop,pop,unpack"H*",<> )]}\EsMsKsN0[lN*1lK[d2%Sa2/d0<X+d*lMLa^*lN%0]dsXx++lMlN/dsM0<J]dsJxp"|dc`