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Re: [TLS] Using Brainpool curves in TLS

Johannes Merkle <johannes.merkle@secunet.com> Wed, 16 October 2013 15:54 UTC

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Date: Wed, 16 Oct 2013 17:53:57 +0200
From: Johannes Merkle <johannes.merkle@secunet.com>
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Cc: Patrick Pelletier <code@funwithsoftware.org>, "tls@ietf.org" <tls@ietf.org>
Subject: Re: [TLS] Using Brainpool curves in TLS
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> Curve25519 picks the smallest value of A that meets the parameters.
Why the smallest, not the largest negative? Why using little /big endian (don't know which was used) instead of the
other? Why choosing exactly these conditions (you phrase it "parameters").

Don't get me wrong. I admit that the construction of Curve25519 is extremely rigid, and even more rigid than that of the
Brainpool curves. I only point to the fact that there is no perfect rigidity.

> is deterministic. Brainpool is close enough that I would say "quite
> rigid" as opposed to "deterministic construction". Basically, the

I think we can agree on that statement.

> length of a PARI script to generate the curve should be short.

Good idea, minimal Kolmogorov complexity should be a good formal definition.



-- 
Johannes

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