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Re: [Ntp] Khronos draft

Dieter Sibold <dsibold.ietf@gmail.com> Tue, 07 February 2023 21:48 UTC

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From: Dieter Sibold <dsibold.ietf@gmail.com>
In-Reply-To: <CAM-HxCPrGVjaEnZWuNRB7odM3ihaiWkHXWDEmdi9aVQKbhgETw@mail.gmail.com>
Date: Tue, 07 Feb 2023 22:47:52 +0100
Cc: draft-ietf-ntp-chronos.authors@ietf.org, NTP WG <ntp@ietf.org>
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To: Neta R S <neta.r.schiff@gmail.com>
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Archived-At: <https://mailarchive.ietf.org/arch/msg/ntp/0MN5Oz7h0mXXfbsPuCNohCKjoog>
Subject: Re: [Ntp] Khronos draft
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Thanks Neta.
Greetings

> Am 07.02.2023 um 21:21 schrieb Neta R S <neta.r.schiff@gmail.com>:
> 
> Hi Dieter,
> 
> 1. We re-phrased this sentence by replacing the word "synchronizes" with "communicates' '.
> 2. We applied your suggestion regarding adding "n".
> 
> I have just uploaded the new version.
> 
> Thanks,
> Neta
> 
> On Mon, Feb 6, 2023 at 6:48 PM Dieter Sibold <dsibold.ietf@gmail.com> wrote:
> After re-reading of the draft I have two remaining questions:
> 
> 1. Sec. 1 Introduction, last paragraph: the third sentence reads. 'First, Khronos periodically synchronizes, in each …'. I understand that under normal circumstances Khronos is just acting as watchdog. But the usage of the word ’synchronize’ might imply that Khronos is also doing the steering of the local clock. Maybe you could re-phrase this sentence.
> 
> 2. Sec. 4.3, third paragraph: I’ve got somehow confused by the sentence: "However, as proved in [Khronos_paper], the probability of this scenario is extremely low even if the attacker controls a large fraction (e.g., 1/4) of the servers in the local Khronos pool.“ I assume the large fraction ‘1/4’ means 1/4 out of n and not out of m. Correct?  Maybe you could consider to write ‘… controls a large fraction (e.g., 1/4) of the n servers in the local Khronos pool.’
> 
> Greetings
> Dieter

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