Re: [Cfrg] Chopping out curves

Trevor Perrin <trevp@trevp.net> Thu, 16 January 2014 21:50 UTC

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Date: Thu, 16 Jan 2014 13:50:12 -0800
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From: Trevor Perrin <trevp@trevp.net>
To: Watson Ladd <watsonbladd@gmail.com>
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Subject: Re: [Cfrg] Chopping out curves
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On Thu, Jan 16, 2014 at 1:40 PM, Watson Ladd <watsonbladd@gmail.com> wrote:
> Dear all,
> Trevor Perrin suggests that we only put in Curve25519/T25519 and
> E383/M382 so implementors can focus on 4 curves ala Suite B. Are there
> any protocols in which larger curves would be useful? Anything we
> might be missing with this decision?

I didn't quite suggest that.

I do feel there should be fewer curves.  Perhaps only curve25519 and
(either Curve3617 or Ed448-Goldilocks).

It takes a great deal of effort to do high-speed, const-time
implementations of a different curve, so we should not diffuse that
effort across too many choices.

Note that Suite B only has 2 curves (P-256 and P-384).


Trevor