Re: [openpgp] Fingerprints and their collisions resistance

Christian Aistleitner <christian@quelltextlich.at> Fri, 04 January 2013 10:53 UTC

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Date: Fri, 04 Jan 2013 11:53:29 +0100
From: Christian Aistleitner <christian@quelltextlich.at>
To: Andrey Jivsov <openpgp@brainhub.org>
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References: <50E530D6.6020609@brainhub.org> <D3684BB5-FDC6-4834-8FAE-C482A25E3FB0@callas.org> <50E5D6AA.6060200@brainhub.org> <874nixev2u.fsf@vigenere.g10code.de> <50E61486.9010209@brainhub.org>
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Subject: Re: [openpgp] Fingerprints and their collisions resistance
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Hi Andrey,

On Thu, Jan 03, 2013 at 03:30:14PM -0800, Andrey Jivsov wrote:
> Instead of 80 bit is security (birthday 
> bounds) SHA-1 is listed as 51 bits on 
> http://en.wikipedia.org/wiki/Message_digest.

Since you mention the 51 bits part again and again ...

Do you have any data / research underpinning this 51 (Besides
Wikipedia)?

After all, the cited Wikipedia page links to the retracted variant of
an article :-(

Otherwise, the best /theoretical/ result that I know of is just
above 60.


Best regards,
Christian



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