Re: [TLS] Comments/Questions on draft-gutmann-tls-encrypt-then-mac-00.txt

Ralph Holz <holz@net.in.tum.de> Wed, 25 September 2013 11:29 UTC

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Date: Wed, 25 Sep 2013 13:30:34 +0200
From: Ralph Holz <holz@net.in.tum.de>
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Subject: Re: [TLS] Comments/Questions on draft-gutmann-tls-encrypt-then-mac-00.txt
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Hi,

> While removing SSL 3.0 support entirely would avoid this kind of
> problem, SSL 3.0 is still sometimes required for interoperability. (Cf.
> the history of RFC 6187: http://tools.ietf.org/html/rfc6176)

We have some empirical data, albeit only for servers. In our most recent
IPv4-wide scan, only 3% of servers required us to downgrade to SSL 3 in
order to complete the handshake. All others were OK with TLS1.

Ralph

-- 
Ralph Holz
I8 - Network Architectures and Services
Technische Universität München
http://www.net.in.tum.de/de/mitarbeiter/holz/
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