Re: [TLS] Encrypting record headers: practical for TLS 1.3 after all?

Peter Gutmann <> Mon, 30 November 2015 01:40 UTC

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From: Peter Gutmann <>
To: Nikos Mavrogiannopoulos <>, Bryan A Ford <>
Thread-Topic: [TLS] Encrypting record headers: practical for TLS 1.3 after all?
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Date: Mon, 30 Nov 2015 01:40:07 +0000
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Subject: Re: [TLS] Encrypting record headers: practical for TLS 1.3 after all?
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Nikos Mavrogiannopoulos <> writes:

>I believe your proposal is a nice example of putting the cart before the
>horse. Before proposing something it should be clear what do you want to
>protect from, what is the threat?

Exactly.  If you want to thwart traffic analysis, you need to do something
like what's done by designs like Aqua ("Towards Efficient Traffic-analysis 
Resistant Anonymity Networks"), or ideas from any of the other anti-traffic-
analysis work that's emerged in the past decade or two.  You get traffic 
analysis resistance by, for example, breaking data into fixed-length 
packets, using cover traffic, and messing with packet timings, not by 
encrypting TLS headers.