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[ntpwg] Antw: Re: Antw: Re: call for adoption (draft-dfranke-ntp-data-minimization)

"Ulrich Windl" <Ulrich.Windl@rz.uni-regensburg.de> Tue, 28 March 2017 07:24 UTC

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Date: Tue, 28 Mar 2017 09:23:47 +0200
From: Ulrich Windl <Ulrich.Windl@rz.uni-regensburg.de>
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Subject: [ntpwg] Antw: Re: Antw: Re: call for adoption (draft-dfranke-ntp-data-minimization)
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> https://datatracker.ietf.org/doc/html/draft-dfranke-ntp-data-minimization 

 I'd suggest to move the explanation for transmit time randomization from "security considerations" to the actual proposal. Also with 11 to 14 bits of randomness for todays clients I wonder whether sending a bunch of 2000 to 16000 bad response packets will remain undetected by the client (in case of an attack).
IMHO it would be consistent to set precision to 3 (the lowest possible precision (0.125s) where NTP will start to work) and use 29 bits of randomness then. Still a half billion attack packets might transit without being detected, but I doubt that.

Ulrich


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