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

mrex@sap.com (Martin Rex) Tue, 17 September 2013 13:15 UTC

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To: Yaron Sheffer <yaronf.ietf@gmail.com>
Date: Tue, 17 Sep 2013 15:14:35 +0200 (CEST)
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From: mrex@sap.com (Martin Rex)
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Subject: Re: [TLS] draft-sheffer-tls-bcp: DH recommendations
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Yaron Sheffer wrote:
> So yes, I agree. Here's from our work-in-progress -01 version:
> 
> As currently specified and implemented, elliptic curve groups are 
> preferable over modular DH groups: they are easier and safer to use 
> within TLS.

Elliptic curve crypto is still fenced with non-expired patent claims,
requires an implementation of elliptic curve algorithms and the
relevant TLS extensions (something which is FAR from universally
available) and elliptic curve technology is considerably more
sensitive to side channel (=timing) attacks that DH, RSA & DSA.

-Martin