Re: [TLS] drop obsolete SSL 2 backwards compatibility from TLS 1.3 draft

Yoav Nir <ynir.ietf@gmail.com> Wed, 24 December 2014 06:40 UTC

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From: Yoav Nir <ynir.ietf@gmail.com>
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Date: Wed, 24 Dec 2014 08:40:10 +0200
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To: Dave Garrett <davemgarrett@gmail.com>
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Subject: Re: [TLS] drop obsolete SSL 2 backwards compatibility from TLS 1.3 draft
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> 
> There's no reason to maintain any backwards support here just for Internet 
> Explorer 2.0 on Windows 3.1.
> 

I’m not objecting to the change, but I am objecting to the hyperbole. The issue is with Internet Explorer 6 on Windows XP, which still exists, but more importantly, a lot of web service clients running on top of Windows XP use the same SCHANNEL library as IE would use, so they issue a SSLv2 ClientHello. Despite Microsoft’s best efforts, there is still a substantial but diminishing install base of XP.

It’s fine for us to break compatibility with these clients, but let’s not pretend it’s some ancient technology that doesn’t exist in the market anymore.

Yoav