Re: [TLS] Publication has been requested for draft-ietf-tls-oldversions-deprecate-05

[John Mattsson <[e-mail]>]

Rob Sayre [e-mail] wrote:

"Is there some data behind this?

I agree with Rob, it would be interesting to get some data on why webrtc need to continue to negotiate and use DTLS 1.0. It would also be interesting to know for how long time webrtc plans to continue negotiate and use DTLS 1.0.

EAP-TLS also have legacy devices that do not support TLS 1.2 and in practice some EAP servers will probably continue to negotiate TLS 1.1 for a while. Still, the EMU WG agreed that the upcoming BCP forbidding use and negotiation of TLS 1.1 was the right thing to do as it puts increased pressure on implementations to improve.

Cheers,
John

From: Rob Sayre <[e-mail]>
Date: Friday, 4 October 2019 at 16:58
To: Eric Rescorla <[e-mail]>
Cc: Cullen Jennings <[e-mail]>, "[e-mail]" <[e-mail]>, Sean Turner via Datatracker <[e-mail]>, IESG Secretary <[e-mail]>, "[e-mail]" <[e-mail]>, John Mattsson <[e-mail]>, Benjamin Kaduk <[e-mail]>
Subject: Re: [TLS] Publication has been requested for draft-ietf-tls-oldversions-deprecate-05



On Fri, Oct 4, 2019 at 9:48 PM Eric Rescorla <[e-mail]<mailto:[e-mail]>> wrote:


On Fri, Oct 4, 2019 at 7:43 AM Rob Sayre <[e-mail]<mailto:[e-mail]>> wrote:
On Fri, Oct 4, 2019 at 9:08 PM Cullen Jennings <[e-mail]<mailto:[e-mail]>> wrote:

I do not think you have consensus for that change to WebRTC - it was discussed extensively. ...

 While that may be true, readers of this list might want to read a rationale, rather than just the results of a negotiation. Is there a rationale somewhere?

It seems strange to put DTLS 1.0 (based on TLS 1.1) into new documents.

A few points.

1. It doesn't pull it in. There's no reference and there's just an informative statement.

Shouldn't there be an informative reference?

2. There is a rationale. In fact, the relevant text pretty much is all rationale.

   All Implementations MUST support DTLS 1.2 with the

   TLS_ECDHE_ECDSA_WITH_AES_128_GCM_SHA256 cipher suite and the P-256

   curve [FIPS186<https://tools.ietf.org/html/draft-ietf-rtcweb-security-arch-20#ref-FIPS186>].  Earlier drafts of this specification required DTLS

   1.0 with the cipher suite TLS_ECDHE_ECDSA_WITH_AES_128_CBC_SHA, and

   at the time of this writing some implementations do not support DTLS

   1.2; endpoints which support only DTLS 1.2 might encounter

   interoperability issues.

Yes, I read this section and I was wondering what the rationale was for the text: "endpoints which support only DTLS 1.2 might encounter interoperability issues." Is there some data behind this? I'm not suggesting a change in the draft without more information, but I do wonder how the WG came to agree on this text.

thanks,
Rob