Re: [Cfrg] Adoption of draft-agl-cfrgcurve-00 as a RG document

Adam Langley <> Mon, 05 January 2015 20:02 UTC

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From: Adam Langley <>
To: Alexey Melnikov <>
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Subject: Re: [Cfrg] Adoption of draft-agl-cfrgcurve-00 as a RG document
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On Mon, Jan 5, 2015 at 11:15 AM, Alexey Melnikov
<> wrote:
> whether you want a particular change be made to the
> document before adoption.

The structure of the current draft anticipates an additional curve and
also signature work so I'd like to point out a couple of changes to
save others having to do so:

1) If no other curves end up being recommended, then the current
generation process is overly complicated and could well be replaced
with a description that mirrors how curve25519 was actually chosen:
i.e. that the minimal sensible A value in Montgomery form be chosen.
It really depends on how important a generic procedure is seen to be.

2) The procedure for generating base points is currently unused and,
if change (1) is done, it could be tweaked to reflect how the
curve25519 base point was generated.

3) If we don't end up saying anything about signatures, all mention of
Edwards curves could conceivably be dropped.

Not to mention that several sections should be greatly expanded upon,
clarified etc. I think such changes can be considered as a given.

To contrast, if you desire changes like "a different curve should be
recommended" then I think that translates to not supporting adoption.



Adam Langley