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Re: [TLS] I-D Action: draft-ietf-tls-rfc4492bis-00.txt

Manuel Pégourié-Gonnard <mpg@polarssl.org> Tue, 02 December 2014 14:34 UTC

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Date: Tue, 02 Dec 2014 15:34:27 +0100
From: Manuel Pégourié-Gonnard <mpg@polarssl.org>
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Subject: Re: [TLS] I-D Action: draft-ietf-tls-rfc4492bis-00.txt
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On 02/12/2014 14:48, Henrick Hellström wrote:
>     Server implementations SHOULD support all of the following cipher
>     suites, and client implementations SHOULD support at least one of
>     them:
> 
>     o  TLS_ECDH_ECDSA_WITH_3DES_EDE_CBC_SHA
>     o  TLS_ECDH_ECDSA_WITH_AES_128_CBC_SHA
>     o  TLS_ECDHE_RSA_WITH_3DES_EDE_CBC_SHA
>     o  TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA.
> 
> Isn't this recommendation problematic? I don't think it is very common 
> for servers to have more than one certificate, and a server can't 
> support all four of these cipher suites, unless it has both one RSA 
> certificate and one EC certificate.
> 
I think this is not a problem since the text is about server _implementations_
not actual server deployment.

I'm more concerned about the choice of ECDH as opposed to ECDHE for the first
two ciphersuites.

Manuel.

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