Re: Self-shrinking MT19937 as stream cipher

Cristiano wrote:
The Berlekamp-Massey algorithm shows that the linear complexity of any bit of the MT19937 is 19937, this means that taking the LSB of MT19937 is equivalent to use a 19937-bit LFSR (also see a recent post on sci.crypt.random-numbers).

In the paper "The Self-Shrinking Generator", Meier and Staffelbach showed that the complexity of the attack for an N-bit self-shrinking LFSR is O(2^(0.69*N)).

Using the LSB of MT19937 to get a self-shrinking generator, we get an attack complexity of O(2^13757) which seems much bigger than the one of any stream cipher.

Why don't use an MT19937 based self-shrinking generator as a stream cipher?

"Why not use ..." or "Why don't we use..." (Hi, Cristiano!)
IIRC, it uses more RAM than other stream ciphers. It wouldn't have a built-in MAC like Phelix. Unlike VMPC, it can't be implemented with a pack of cards. How's its speed? Could it have unexpected vulnerabilities, like RC4?

--Mike Amling
.

Relevant Pages

  • Re: Self-shrinking MT19937 as stream cipher
    ... MT19937 is equivalent to use a 19937-bit LFSR (also see a recent ... In the paper "The Self-Shrinking Generator", ... Although a low linear complexity is proof of insecurity, ... attribute of a stream cipher. ...
    (sci.crypt)
  • Re: Self-shrinking MT19937 as stream cipher
    ... MT19937 is equivalent to use a 19937-bit LFSR (also see a recent ... In the paper "The Self-Shrinking Generator", ... showed that the complexity of the attack for an N-bit self-shrinking ... Anyone who might consider your stream cipher would have to stop at AES or any new block cipher and ask if there is anything extra your stream cipher provides. ...
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  • Re: Self-shrinking MT19937 as stream cipher
    ... MT19937 is equivalent to use a 19937-bit LFSR (also see a recent ... In the paper "The Self-Shrinking Generator", ... There is not a single "the" attack. ... MT also argue against its use as a stream cipher. ...
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  • Re: Self-shrinking MT19937 as stream cipher
    ... MT19937 is equivalent to use a 19937-bit LFSR (also see a recent ... In the paper "The Self-Shrinking Generator", ... Using the LSB of MT19937 to get a self-shrinking generator, ... one of any stream cipher. ...
    (sci.crypt)
  • Re: Self-shrinking MT19937 as stream cipher
    ... MT19937 is equivalent to use a 19937-bit LFSR (also see a recent ... In the paper "The Self-Shrinking Generator", ... showed that the complexity of the attack for an N-bit self-shrinking ... Using the LSB of MT19937 to get a self-shrinking generator, ...
    (sci.crypt)