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Re: [Cfrg] I-D Action: draft-irtf-cfrg-dragonfly-03.txt

"Blumenthal, Uri - 0558 - MITLL" <uri@ll.mit.edu> Tue, 04 February 2014 20:42 UTC

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From: "Blumenthal, Uri - 0558 - MITLL" <uri@ll.mit.edu>
To: Robert Ransom <rransom.8774@gmail.com>
Date: Tue, 04 Feb 2014 15:42:48 -0500
Thread-Topic: [Cfrg] I-D Action: draft-irtf-cfrg-dragonfly-03.txt
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Cc: "cfrg@ietf.org" <cfrg@ietf.org>
Subject: Re: [Cfrg] I-D Action: draft-irtf-cfrg-dragonfly-03.txt
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On Feb 4, 2014, at 14:41 , Robert Ransom <rransom.8774@gmail.com> wrote:
> On 2/4/14, Dan Harkins <dharkins@lounge.org> wrote:
>>  This is mentioned in section 6.3 of RFC 5931 (dragonfly as an EAP
>> method), knowledge of r where PE = r * G can enable a dictionary
>> attack. But knowledge of r requires doing a discrete logarithm. A discrete
>> logarithm is assumed to be "computationally infeasible" and you're talking
>> about doing 2^40 of them!?!
> 
> <http://cr.yp.to/papers.html#nonuniform> is relevant here.  It
> discusses several other ‘attacks’ of this general type, and explains
> why they should not be taken seriously.
> 
> Robert Ransom

Robert,

I think you hit the nail on the head, and made an excellent point.

Thanks!
--
Regards,
Uri               <uri@ll.mit.edu>
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