Re: [TLS] I-D Action: draft-ietf-tls-certificate-compression-01.txt

Ilari Liusvaara <ilariliusvaara@welho.com> Thu, 14 December 2017 21:46 UTC

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Date: Thu, 14 Dec 2017 23:46:50 +0200
From: Ilari Liusvaara <ilariliusvaara@welho.com>
To: Martin Thomson <martin.thomson@gmail.com>
Cc: Victor Vasiliev <vasilvv@google.com>, "tls@ietf.org" <tls@ietf.org>
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Subject: Re: [TLS] I-D Action: draft-ietf-tls-certificate-compression-01.txt
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On Tue, Dec 12, 2017 at 06:43:19PM -0600, Martin Thomson wrote:
> On Tue, Dec 12, 2017 at 6:32 PM, Victor Vasiliev <vasilvv@google.com>; wrote:
> > https://github.com/tlswg/certificate-compression/pull/8
> 
> That's a lot cleaner.  Thanks.  Some minor quibbles, but I like this
> construction far better.

Yeah, same here, I like this construction far better than the -01 one.

> A question about client certificates prior to TLS 1.3: Are we happy
> making compression for client certificates only available in TLS 1.3
> (or higher if we can assume that we will maintain parity in future)?
> I think that I can live with that.

As others have said, this extension is basically undeployable with
TLS 1.2 because middleboxes.


Also, assuming parity in the future might not be a good idea. Does
anyone have any idea what TLS 1.4 might be about[1] (TLS 2.0 would
likely be about cleaning representation, but that would likely be a
bad idea)?


[1] Not Post-Quantum Cryptography. Integrating PQC into TLS 1.3 is not
a difficult task (once you know the trick). And I do not see TLS
changes making it any easier without weakening security.



-Ilari