Random Numbers: Nothing Left to Chance

"The generation of random numbers is too important to be left to chance." --Robert Coveyou

It is often said that mathematics is about understanding patterns and that these patterns are what makes mathematics beautiful. This article, however, is about how mathematics may be used to create, or at least simulate, randomness, the lack of patterns. Suprisingly, we will see that it is difficult to create random behavior (in fact, the words "create randomness" may sound a little jarring) and to determine when we have successfully done it.

tovább

( NagyZ v | 2008. 03. 03., h – 17:01 )

ta'n matematikusnak tetszik lenni?

In 1997, Makoto Matsumoto and Takuji Nishimura found a new random number generator, which they named the Mersenne Twister, with the phenomenally large period 219937 - 1. Though it is not safe to use in cryptographical applications, it generates random numbers very efficiently and is now in wide use.

namost, en is ezt hasznaltam az egyik kutatasban a T-Comnal. miert nem alkalmas titkositasra? mi a baja? tudja valaki? :)

http://www.archivum.info/sci.crypt/2005-07/msg00497.html

"Why is MT non-secure ?

MT was not designed as a cryptographic generator. There's a
straightforward way (described in the MT paper) to reconstruct the
internal state. Remember where it says something like it's
equidistributed in 623 dimensions? That means that if you start
counting in 624 or more dimensions, all bets are off. That's
different from a cryptographic generator, which can't be distinguished
from uniform no matter how many dimensions you use."

( mogorva v | 2008. 03. 03., h – 17:41 )

baromi jó írás, a hivatkozott dilbert pedig megalol B-)

( Lightgod | 2008. 03. 03., h – 18:15 )

Ilyen kellllllllllll
--
by lightgod