Re: [Cfrg] Summary

Nico Williams <nico@cryptonector.com> Fri, 02 January 2015 04:38 UTC

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Date: Thu, 1 Jan 2015 22:38:28 -0600
From: Nico Williams <nico@cryptonector.com>
To: Watson Ladd <watsonbladd@gmail.com>
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Subject: Re: [Cfrg] Summary
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On Thu, Jan 01, 2015 at 10:50:49AM -0500, Watson Ladd wrote:
> On Thu, Jan 1, 2015 at 9:49 AM, Kurt Roeckx <kurt@roeckx.be> wrote:
> > - What are the various proposals?  The IETF datatracker doesn't
> >   seem to known all proposals, and I think there are proposals
> >   that just don't have a document yet.
> 
> Good question: the answer is that at the 255 bit level, for ECDH the
> current proposals are both Curve25519. But one uses the same basepoint
> as existing code, and the other doesn't. This difference doesn't
> affect security in any way. It's the only difference.

If it's the only difference then picking Curve25519's generator is the
obvious way to go, since changing it would be a gratuitous change and
Curve25519 has seen wide deployment.

Nico
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