Re: [TLS] draft-rhrd-tls-tls13-visibility at IETF101

Melinda Shore <> Tue, 13 March 2018 17:21 UTC

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From: Melinda Shore <>
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Date: Tue, 13 Mar 2018 09:21:04 -0800
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Subject: Re: [TLS] draft-rhrd-tls-tls13-visibility at IETF101
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On 3/13/18 6:48 AM, Jim Reid wrote:
> Stephen, the opposite PoV is equally valid. There was no consensus in
> Prague NOT to work on the topic. The mood of the room was evenly
> divided.

To clarify, this isn't voting.  If there's no agreement in
either direction there's no agreement (and I hope the default
in the IETF is not that in the absence of agreement, work
goes forward).  The problem is how to come to agreement, and
what that typically involves is refining the proposal to
address objections.

> IIRC the supporters of draft-green-tls-static-dh-in-tls13 agreed to
> drop that draft and come back with a new one which would hopefully be
> more likely to get WG consensus. That draft has now arrived. It’s
> unreasonable to deny the new I-D a fair hearing and even worse to
> reject it out of hand.

It's surprising that it got agenda time without mailing list
discussion.  Aside from the changes to the key
exchange there are some clear usability problems.  While
usability usually lies outside the purview of the IETF's
technical work, in this case the work is premised on the
ability of the user to consent (or not) to sharing keying
material with a third party, which in turn suggests that
they're presented with the question at the time the
session is initiated, so that the extension isn't sent in
the ClientHello.  Sounds like a click-through problem,
tbh, where the user has little practical control over whether
or not their data are shared with a third party.


Software longa, hardware brevis

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