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Re: [saag] A case against algorithm agility (long)

Benjamin Kaduk <kaduk@MIT.EDU> Sun, 04 May 2014 03:10 UTC

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Date: Sat, 3 May 2014 23:10:49 -0400 (EDT)
From: Benjamin Kaduk <kaduk@MIT.EDU>
To: ianG <iang@iang.org>
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Subject: Re: [saag] A case against algorithm agility (long)
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On Sat, 3 May 2014, ianG wrote:

> 4.  Marginality.  Any benefits from tweaking/swapping/improving blackbox
> algorithms are marginal and/or esoteric.  For the most part, any cipher
> gets you 99.999% of the grade.  Same with any HMAC, any mode properly
> implemented.  The only people who can or will crack weaker algorithms
> (DES?  RC4) are people who will also bypass the crypto, and are already
> doing it.

My apologies for cherry-picking just a single point, but commercial DES 
crackers are in the $200, 1-day range these days.  That there is even a 
commercial market for it suggests that they are in use, and not just by 
people who could by pass the crypto.

-Ben Kaduk

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