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Re: [TLS] Security review of TLS1.3 0-RTT

Nico Williams <nico@cryptonector.com> Wed, 03 May 2017 04:23 UTC

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Date: Tue, 02 May 2017 23:21:51 -0500
From: Nico Williams <nico@cryptonector.com>
To: Peter Gutmann <pgut001@cs.auckland.ac.nz>
Cc: Benjamin Kaduk <bkaduk@akamai.com>, TLS WG <tls@ietf.org>
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Subject: Re: [TLS] Security review of TLS1.3 0-RTT
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On Tue, May 02, 2017 at 11:49:31PM +0000, Peter Gutmann wrote:
> Benjamin Kaduk <bkaduk@akamai.com> writes:
> >I thought TLS clients were supposed to have even worse clocks (in terms of
> >absolute time) than Kerberos clients.
> 
> Many of the devices I work with don't have clocks (at best they have non-
> persistent monotonic counters), so I guess that's true in some sense...

Yeah, but a non-persistent clock is fine if the client can learn time
from the server (and keep a different offset from system time to every
server if need be, learning system time from one of them, or from NTP,
or whatever).

Nico
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