Subject: [Uta] Kathleen Moriarty's Yes on draft-ietf-uta-tls-bcp-09: (with COMMENT)

From: "Kathleen Moriarty" <[email-masked]>
Date: Tue, 17 Feb 2015 16:48:13 -0800

Kathleen Moriarty has entered the following ballot position for
draft-ietf-uta-tls-bcp-09: Yes

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COMMENT:
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Thanks for your work on this very helpful draft!

I just have a few comments/questions.

Section 5. Applicability statement:
Should this include application authors (mentioned in section 7.1) and
Developers who can set the defaults for implementations of TLS to help
operators that are mentioned in this applicability statement?  I see the
sentence is phrased for 'deployment recommendations', but maybe this
should also have a sentence or two on development recommendations.

Not for this draft, but this one raised a question for me.
Section 7.3: If you look at the following text:
   Unfortunately, many TLS/DTLS cipher suites were defined that do not
   feature forward secrecy, e.g., TLS_RSA_WITH_AES_256_CBC_SHA256.  This
   document therefore advocates strict use of forward-secrecy-only
   ciphers.
Should we be thinking about updates to the TLS registry to reflect this
recommendation?  That's probably not this draft, but a follow on to
provide the needed 'specification required'.  I'm sure a lot more thought
might be needed for that and maybe support for features like PFS is added
in a table if older recommendations that don't meet this are not
removed.
http://www.iana.org/assignments/tls-parameters/tls-parameters.xhtml

HTTPbis went to the trouble of creating a blacklist of cipher suites that
includes ones in the TLS registry.  They did take the MTI recommendation
that is in this draft, which is good.  See section 9.2 and appendix A.
https://datatracker.ietf.org/doc/draft-ietf-httpbis-http2/