Re: compare-by-hash (was Re: sharing /etc/passwd)

From: Jacques A. Vidrine (nectar_at_FreeBSD.org)
Date: 09/28/04

  • Next message: David Schultz: "Re: compare-by-hash (was Re: sharing /etc/passwd)" 
    Date: Tue, 28 Sep 2004 10:15:41 -0500
To: Giorgos Keramidas <keramida@linux.gr>

    On Tue, Sep 28, 2004 at 12:14:05PM +0300, Giorgos Keramidas wrote:
    > There is one difference between ``looking for collisions'' and being
    > bitten by undetected collisions though.
    >
    > If the probability of a collision just happening with random user data
    > is 1/(2^128) we can't be sure that it will necessarily take the
    > transfer of an average number of 2^127 blocks before a collision
    > happens. You might get one at the very first pair of blocks and then
    > no collisions ever after until the Sun burns out.
    >
    > Using two different hashes for the same set of input data, which David
    > G. Andersen proposed, seems like a nice idea though.

    If you buy the "logic" of the paper, this would not make much
    difference. After all, composing two hashes just gives you another
    hash with a longer bit length.

    This paper needs a lot more peer review, although I'm not sure that
    many take it seriously enough to bother.

    Cheers, 

    -- 
Jacques A Vidrine / NTT/Verio
nectar@celabo.org / jvidrine@verio.net / nectar@FreeBSD.org
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  • Next message: David Schultz: "Re: compare-by-hash (was Re: sharing /etc/passwd)"

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