On Tuesday, December 31, 2002, at 11:41 AM, Michael Cardenas wrote:
Strong crypto is, ipso facto, resistant to all of the above. For the obvious reason that the specific solution to a cipher is like a Dirac delta function (a spike) rising above a featureless plain, this in terms of the usual hill-climbing or landscape-learning models which all of the above use in one form or another.How do you all see the future use of biologically based systems affecting cryptography in general?By biologically based systems I mean machine learning, genetic algorithms, chips that learn (like Carver Mead's work), neural networks, vecor support machines, associative memory, etc.
Cryptanalysis of weak crypto, in terms of mundane things like passphrase guessing, finding images tagged with stego code, etc., already in some cases makes use of these tools. Bob Baldwin's Crytpographer's Workbench used learning algorithms a long time ago.
Strong math wins out over weak crypto any day, and attempting to brute force a cipher with even a swimming pool full of Adleman machines will not work: if a 400-digit number takes, for instance, a million Pentium 4 years to brute force factor, then how long does a 600-digit number take?
(And using larger RSA moduli is of course trivial...)
Homework: Using the estimates Schneier, Diffie, Hellman, and others have made for the number of computer operations to break ciphers of various kinds, describe a reasonable cipher and modulus or key length which will take more energy than there is in the entire universe to break. The answer, in terms of how small the key or modulus is, may surprise you.
It seems to me that computer science based on writing longer and longer streams of instructions is coming to an end, as it cannot possibly scale. We now have supercomputers that can execute 35 trillion instructions per second, but if someone has to write all of those instuctions, what good are they? Also, it seems that the brain has immensely powerful visual processing power, without having millions of lines of code written to do so.
This is AI, not crypto.
I only ask this because I'm deciding whether to study computational neuroscience or cryptography in grad school.
Learn some more of each and your decision should be an easy one to make. --Tim May
