Re: [TLS] Suspicious behaviour of TLS server implementations

Peter Gutmann <> Thu, 22 September 2016 05:11 UTC

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From: Peter Gutmann <>
To: Martin Thomson <>
Thread-Topic: [TLS] Suspicious behaviour of TLS server implementations
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Date: Thu, 22 Sep 2016 05:11:39 +0000
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Subject: Re: [TLS] Suspicious behaviour of TLS server implementations
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Martin Thomson <> writes:

>The advantage with deploying a new protocol is that you can be strict. If, 
>for example, all of the browsers implement TLS 1.3 and are strict, then 
>Amazon won't be able to deploy a buggy 1.3 implementation without noticing 
>pretty quickly.  You might suggest that that's aspiration to the point of 
>delusion, but in fact it worked out pretty well with HTTP/2 deployment.  We 
>didn't squash ALL of the nasty bugs, but we got most of them.

It also means you're going to be in for a rude shock when you encounter the
ocean of embedded/SCADA/IoT devices with non-mainstream TLS implementations.
The reason why HTTP/2 "works" is that it essentially forked HTTP, HTTP/2 for
Google, Amazon, etc, and the browser vendors, and HTTP 1.1 for everything 
else that uses HTTP as its universal substrate.  As a result there will be 
two versions of HTTP in perpetuity, HTTP 1.1 and HTTP-whatever-the-current-

(Should I mention TLS-LTS here? :-).