Re: [Cfrg] Safecurves draft

Manuel Pégourié-Gonnard <mpg@elzevir.fr> Wed, 08 January 2014 18:40 UTC

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Subject: Re: [Cfrg] Safecurves draft
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On 08/01/2014 18:11, Watson Ladd wrote:
> draft-ladd-safecurves contains the Safecurves with orders
> 2^255+\epsilon and higher.
> I forgot to update the TOC, but that shouldn't stop the substantive
> conversation.
> 
> Does anyone object to these curves being approved for IETF standard
> body use/typos/general nastiness?

I'm in favour of these curves being approved for IETF use.

I think the draft itself, however, should be expanded to go into some details
about the advantages of the curves and the differences with existing curves.

I have one question about the curves themselves: why are there two Montgomery
curves over GF(2^383-187)? I thought the curves were chosen by a deterministic
process, and the smallest 'a' coefficient giving the desired properties was
always used.

Also, is it on purpose that you didn't include E-521 in your draft?

Manuel.