Re: [DNSOP] Whiskey Tango Foxtrot on key lengths...

Paul Hoffman <paul.hoffman@vpnc.org> Wed, 02 April 2014 14:04 UTC

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From: Paul Hoffman <paul.hoffman@vpnc.org>
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Date: Wed, 2 Apr 2014 07:04:37 -0700
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To: Olafur Gudmundsson <ogud@ogud.com>
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Subject: Re: [DNSOP] Whiskey Tango Foxtrot on key lengths...
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On Apr 1, 2014, at 8:02 PM, Olafur Gudmundsson <ogud@ogud.com> wrote:

> 
> On Apr 1, 2014, at 10:48 PM, Paul Hoffman <paul.hoffman@vpnc.org> wrote:
> 
>> On Apr 1, 2014, at 7:37 PM, Olafur Gudmundsson <ogud@ogud.com> wrote:
>> 
>>> Why not go to a good ECC instead ? (not sure which one, but not P256 or P384) 
>> 
>> Why not P256 or P384? They are the most-studied curves. Some of the newer curves do have advantages, but they are also newer.
>> 
>> --Paul Hoffman
> 
> 
> The verification performance is bad, P256 takes 24x times longer to verify a signature than 2048 bit RSA key. 
> Studied != good performance

I believe that there are no elliptic curves that get *much* better verification speeds that P256/P384. Some are a bit faster, but not even close to RSA2048. From your question "Why not go to a good ECC instead", I assumed you were caring about predictability against attacks and key length, which are the strengths of elliptic curve cryptography.

--Paul Hoffman