Re: [TLS] TLS 1.2 Long-term Support Profile vs HTTP/2.0

Peter Gutmann <pgut001@cs.auckland.ac.nz> Sun, 03 April 2016 08:18 UTC

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From: Peter Gutmann <pgut001@cs.auckland.ac.nz>
To: Nikos Mavrogiannopoulos <nmav@redhat.com>, "<tls@ietf.org>" <tls@ietf.org>
Thread-Topic: TLS 1.2 Long-term Support Profile vs HTTP/2.0
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Date: Sun, 3 Apr 2016 08:18:20 +0000
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Subject: Re: [TLS] TLS 1.2 Long-term Support Profile vs HTTP/2.0
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Nikos Mavrogiannopoulos <nmav@redhat.com>; writes:

>I liked the idea of an LTS profile for TLS 1.2, however I just realized that
>RFC7540 [0] blacklists (with no rationale) 3 out of the 4 LTS ciphersuites
>and I'm wondering how practically useful will be that profile.

I chose the two sets of algorithms that were secure and had the most
widespread acceptance/support/popularity/whatever, in other words the ones
where there was the biggest chance of developers being able to say "yeah, we
do that already".

>[0]. https://tools.ietf.org/html/rfc7540#appendix-A

I think the reason why there's no rationale is because there's no rational
explanation for lumping TLS_DHE_RSA_WITH_AES_256_CBC_SHA256 in with the likes
of TLS_RSA_EXPORT_WITH_RC4_40_MD5.

Peter.