Re: [TLS] draft-sheffer-tls-bcp: DH recommendations

Yaron Sheffer <yaronf.ietf@gmail.com> Wed, 18 September 2013 10:08 UTC

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Date: Wed, 18 Sep 2013 13:07:58 +0300
From: Yaron Sheffer <yaronf.ietf@gmail.com>
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To: Peter Gutmann <pgut001@cs.auckland.ac.nz>
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Cc: "tls@ietf.org" <tls@ietf.org>
Subject: Re: [TLS] draft-sheffer-tls-bcp: DH recommendations
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Hi Peter,

I fully agree that PFS is indeed important. There are multiple issues 
with MODP DH in TLS (performance is just one of them). So I'd like to 
recommend EC DHE instead - which makes this discussion moot.

Thanks,
	Yaron

On 09/18/2013 12:54 PM, Peter Gutmann wrote:
> Yaron Sheffer <yaronf.ietf@gmail.com>; writes:
>
>> Please see the later discussion, in particular
>> http://www.ietf.org/mail-archive/web/tls/current/msg09924.html.
>
> I've been following the discussion, but none of it really supports going to
> 2048 rather than just 1280 or 1536.  In addition, as Yoav pointed out, there's
> a big different between solving the DLP in 1024 bits and stealing an any-size-
> you-want long-term RSA key.
>
> Peter.
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