Re: [TLS] [perpass] Fwd: New Version Notification for draft-sheffer-tls-bcp-00.txt

Nikos Mavrogiannopoulos <> Mon, 09 September 2013 08:36 UTC

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Date: Mon, 09 Sep 2013 10:35:59 +0200
From: Nikos Mavrogiannopoulos <>
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Subject: Re: [TLS] [perpass] Fwd: New Version Notification for draft-sheffer-tls-bcp-00.txt
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On 09/09/2013 08:59 AM, Yoav Nir wrote:

> Those tables are mostly quoting NIST publications, so while it seems
> like there's many sources, they're not really independent. There are
> academic results in factoring 768-bit numbers, so with sufficient
> thrust (and the NSA has more thrust than most academics), it's
> perfectly logical to suspect that the NSA can factor 1024-bit
> numbers. That would be a breakage of RSA, not D-H or DSA. 

 While I am not in par with the advances in solving the DLOG problem,
the ECRYPT 2010 report on key sizes mentions in section 6.1: "According
to the state of the art the difficulty of solving DLOG in prime order
fields of size 2^n is, up to constants, asymptotically equivalent to
that of breaking n-bit RSA". Given that all reports on key sizes agree
on that (ECRYPT is not related to NIST in any way), I wouldn't ignore
these recommendations.