Re: [Cfrg] draft-ladd-safecurves-02

Manuel Pégourié-Gonnard <mpg@elzevir.fr> Sat, 11 January 2014 15:58 UTC

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Subject: Re: [Cfrg] draft-ladd-safecurves-02
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On 11/01/2014 01:37, Dan Brown wrote:
> I'm going to try to write up to CFRG my disagreements soon.
> 
I'm looking forward to reading them.

FWIW, I don't agree with every argument as stated on the site (eg, I don't
believe it's fair to quote "no data-dependant branches or memory access
patterns" as properties of the curves), but I still think those curves are an
interesting addition to the current set of curves mainly for the following reasons:

* no unexplained constants as opposed to the NIST "random" prime curves (and
better performance than the Brainpool curves). Even if NIST curves turn out not
to be weak, we currently don't know, and doubt is an issue in itself.
* ease of (correct) implementation
* performance.

> Maybe I'm old school, but I'd expect references to be stable and dated.
> 
Agreed.

Manuel.