Re: [TLS] Fwd: New Version Notification for draft-moriarty-tls-oldversions-diediedie-00.txt

Alessandro Ghedini <> Mon, 09 July 2018 18:14 UTC

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Date: Mon, 09 Jul 2018 19:14:38 +0100
From: Alessandro Ghedini <>
To: Kathleen Moriarty <>
Cc: "<>" <>
Message-ID: <20180709181438.GA28316@mandy>
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Subject: Re: [TLS] Fwd: New Version Notification for draft-moriarty-tls-oldversions-diediedie-00.txt
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On Mon, Jul 09, 2018 at 12:40:54PM -0400, Kathleen Moriarty wrote:
> Hello,
> Stephen and I posted the draft below to see if the TLS working group
> is ready to take steps to deprecate TLSv1.0 and TLSv1.1.  There has
> been a recent drop off in usage for web applications due to the PCI
> Council recommendation to move off TLSv1.0, with a recommendation to
> go to TLSv1.2 by June 30th.  NIST has also been recommending TLSv1.2
> as a baseline.  Applications other than those using HTTP may not have
> had the same reduction in usage.  If you are responsible for services
> where you have a reasonable vantage point to gather and share
> statistics to assess usage further, that could be helpful for the
> discussion.  We've received some feedback that has been incorporated
> into the working draft and feelers in general have been positive.  It
> would be good to know if there are any show stoppers that have not
> been considered.

I'm very much in favour of deprecating pre-TLSv1.2 versions, and this seems
like a good time to start.

As far as usage goes, it's still quite significant, at least as far as
Cloudflare is concerned. See the chart from a couple of months ago at:

Particularly for TLSv1.0, which is still at ~10% of all TLS connections we see,
while TLSv1.1 is at ~0.2%. Given this it's unlikely we (Cloudflare) will be
able to disable them by default any time soon, but we might be able to
understand the situation better once we do a more thorough analysis.