Hi Hernán,

Thank you for your question. I just spent some time looking it up and I found this in wikipedia. http://en.wikipedia.org/wiki/Mersenne_twister

"Application Unlike Blum Blum Shub, the algorithm in its native form is not suitable for cryptography. Observing a sufficient number of iterates (624 in the case of MT19937) allows one to predict all future iterates. Combining the Mersenne twister with a hash function solves this problem, but slows down generation.

"Another issue is that it can take a long time to turn a non-random initial state into output that passes randomness tests, due to its size. A small Lagged Fibonacci generator or Linear congruential generator gets started much quicker and is usually used to seed the Mersenne Twister. If only a few numbers are required and standards aren't high it is simpler to use the seed generator. But the Mersenne Twister will still work.

"For many other applications, however, the Mersenne twister is fast becoming the random number generator of choice. Since the library is portable, freely available and quickly generates good quality random numbers it is rarely a bad choice.

"It is designed with Monte carlo simulations and other statistical simulations in mind. Researchers primarily want good quality numbers but also benefit from its speed and portability."

Notice that it says that the PRNG is not appropriate for Cryptographic applications because of the possibility of retrieving a sequence that is predictable.

Because of this I would say that the Cryptography Repository may not be the right place to put this. If you would like some help creating a separate repository for this code I would be happy to help you.

What does everyone else think about including this PRNG in the Cryptography Repository? I suppose that we could include a warning not to use this for cryptographic applications.

Thoughts?

Thanks,

Ron Teitelbaum Squeak Cryptography Team Leader

-----Original Message----- From: Hernán Morales

(English readers scroll down a little bit...) No sé si este es el lugar apropiado para enviar esto. Hace un tiempo porté parcialmente el MersenneTwister desde un fuente C++ muy muy feo, sucio, malo, etc. a VisualSmalltalk. No recuerdo porqué lo hice, capaz que estaba con fiebre o algo así... como sea, ¿le sirve a alguien esto acá?

Hello. I don't know if this is the right place for posting this. Some time ago I've partially ported the MersenneTwister from an ugly, dirty and bad C++ source to VisualSmalltalk. I don't know why I've done that, maybe I was sick or something... anyway, it is useful to anybody here?

Mersenne Twister Home Page: http://www.math.sci.hiroshima-u.ac.jp/~m-mat/MT/emt.html

---

Cryptography mailing list Cryptography@lists.squeakfoundation.org http://lists.squeakfoundation.org/cgi-bin/mailman/listinfo/cryptography