Messages in this thread | | | Date | Fri, 17 May 1996 19:31:48 +0200 | From | Harald Anlauf <> | Subject | Re: CONFIG_RANDOM (compromise?) |
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>>>>> "tytso" == "Theodore Y Ts'o" <tytso@MIT.EDU> writes:
[...] tytso> For example, with tytso> the generators above, one can determine V(n+1) given knowledge of tytso> V(n). In fact, it has been shown that with these techniques, even if tytso> only one bit of the pseudo-random values is released, the seed can be tytso> determined from short sequences.
You mean linear congruential generators.
(Linear congruential generators are probably the best understood generators, just because of their simplicity, Fibonacci type maybe next.)
tytso> Not only have linear congruent generators been broken, but techniques tytso> are now known for breaking all polynomial congruent generators tytso> [KRAWCZYK].
In this RFC, I find only
[KRAWCZYK] - How to Predict Congruential Generators, Journal of Algorithms, V. 13, N. 4, December 1992, H. Krawczyk
as reference.
So does this include also the (lagged) Fibonacci generators? When you apply methods to improve the quality of randomness, like those proposed by Luescher?
Still, I maintain that DEK's generator is superior to what most people use. For non-networked machines, where security is not first priority, a clearly leaner and (I think) acceptable solution.
Cheers, -ha
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