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Re: [Ntp] NTP Security (was NTPv5: big picture)

Philip Prindeville <philipp@redfish-solutions.com> Fri, 22 January 2021 02:34 UTC

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From: Philip Prindeville <philipp@redfish-solutions.com>
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Date: Thu, 21 Jan 2021 19:34:28 -0700
Cc: Miroslav Lichvar <mlichvar@redhat.com>, NTP WG <ntp@ietf.org>, Kurt Roeckx <kurt@roeckx.be>
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To: Magnus Danielson <magnus@rubidium.se>
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Subject: Re: [Ntp] NTP Security (was NTPv5: big picture)
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> On Jan 19, 2021, at 5:24 AM, Magnus Danielson <magnus@rubidium.se> wrote:
> 
>> I think the point is that you cannot bootstrap secure time out of
>> nothing.
> That's a conjecture, yet to be proven.


No, that's basic Information Theory.  Lost or non-existent information can't be recreated from a void.

...

>> You either do full validation using some trusted time source
>> (e.g. RTC), or you don't.
> 
> RTC is not a trusted time source. 


I think I'm more likely to trust that which I can control or verify for myself, than that which I can't.

-Philip

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