A question: assuming, you have a class of random number generators with lots of internal state. (Lots: like >>10^6 bits). Let's say the evolution through state space of that generator is provably reversible (or nearly reversible), and that the Hamiltonian of the system is stochastic (system evolution is a randomwalk in state space). The result is a pseudorandom number generator with a ridiculously long periode, and good randomness of output, obviously. A simple cypher based on it would exchange the pseudorandom generator state (the key) through a secure channel, similiarly to a one time pad.
Can someone point me towards papers describing construction of above generators? I'm thinking about reversible cellular automata (is Gutowitz the only guy who did CA crypto?) or automata networks with changing connection geometry (i.e. the connection is also encoded in the state and changes with each iteration) with the number of total iterations estimated from lightcone considerations. Point of this: * algorithmic construction of PRNGs with provable properties * lots of internal state, hence bit leakage even for a lot of messages buys attacker little * scalable (add more state as hardware improves) * directly mappable to hardware, very good parallelism Any pointers? On Wed, 27 Feb 2002, Khoder bin Hakkin wrote: > Cipher mixer with random number generator > > Abstract > > An encryption device has a random number generator whose output is > combined by exclusive-or with plaintext input which has been encrypted > by a first block cipher. The combined exclusive-or output is encrypted > with a second block cipher mechanism which produces a second enciphered > output. The output of the random number generator is also encrypted by a > third block cipher mechanism which produces a third enciphered output. > The first and second block cipher mechanisms differ from each other. > > United States Patent > 6,351,539 > February 26, 2002 > -- Eugen* Leitl <a href="http://leitl.org">leitl</a> ______________________________________________________________ ICBMTO: N48 04'14.8'' E11 36'41.2'' http://www.leitl.org 57F9CFD3: ED90 0433 EB74 E4A9 537F CFF5 86E7 629B 57F9 CFD3 --------------------------------------------------------------------- The Cryptography Mailing List Unsubscribe by sending "unsubscribe cryptography" to [EMAIL PROTECTED]