Re: [Cfrg] Comparing ECC curves

Benjamin Black <b@b3k.us> Wed, 23 July 2014 22:34 UTC

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From: Benjamin Black <b@b3k.us>
Date: Wed, 23 Jul 2014 15:33:49 -0700
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To: Phillip Hallam-Baker <phill@hallambaker.com>
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Subject: Re: [Cfrg] Comparing ECC curves
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On Wed, Jul 23, 2014 at 3:28 PM, Phillip Hallam-Baker <phill@hallambaker.com
> wrote:

>
> 3) Do we need to consider 2^192 work factor?
>
> I can't see any case where I am interested in a work factor of 2^192.
> Either I am willing to make some concession to performance or I want
> it gold plated and 2^256. I would quite like to see the 2^192 work
> factor nuked.
>
>
Phillip,

This was our conclusion, as well. If you haven't seen it, here's the NUMS
TLS draft which only specifies the twisted Edwards curves at 128 and 256
bit security levels:
http://tools.ietf.org/id/draft-black-tls-numscurves-00.txt


Ben