Re: [TLS] Rethink TLS 1.3

Hanno Böck <> Sun, 23 November 2014 00:46 UTC

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Date: Sun, 23 Nov 2014 01:46:20 +0100
From: Hanno Böck <>
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Subject: Re: [TLS] Rethink TLS 1.3
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On Sat, 22 Nov 2014 14:15:30 -0800
Watson Ladd <> wrote:

> It's clear what the security claims of TLS are be: a TLS connection
> between two parties ensures that data sent between them isn't
> intercepted or manipulated, and that they are who they claim to be.

I think it's really a bit more tricky than that.

Adding to these one should probably add some confidentiality claims.
However what are the confidentiality claims of TLS? I don't really know.

If I grab my mail through imap or pop3 I can probably assume that my
password and the content of my comm is safe. However if I surf to
https blog X then probably the pure size of my connection packets will
reveal which article on X I'm reading right now.
The CRIME attack has revealed how powerful sidechannels can be.

So what exactly are the confidentiality claims of TLS?

Hanno Böck