Re: [TLS] analysis of wider impact of TLS1.3 replayabe data

Colm MacCárthaigh <colm@allcosts.net> Mon, 14 March 2016 16:34 UTC

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Date: Mon, 14 Mar 2016 09:34:48 -0700
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From: =?UTF-8?Q?Colm_MacC=C3=A1rthaigh?= <colm@allcosts.net>
To: Bill Cox <waywardgeek@google.com>
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Subject: Re: [TLS] analysis of wider impact of TLS1.3 replayabe data
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On Sun, Mar 13, 2016 at 12:04 PM, Bill Cox <waywardgeek@google.com>; wrote:
>
> IMO, 0-RTT is the most important new feature in TLS 1.3 ...  Speed really
> _is_ that important.
>

I just want to be super explicit on this. There is a trade off to be made
here between fast and loose Vs security and safety. My take is that speed
absolutely is not so important that forward-secrecy for user requests, or
replay safety for applications should be compromised.

Even better speed benefits can be had by using persistent connections,
which incidentally are also a little more robust against traffic analysis.

-- 
Colm