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[Ntp] Antwort: Re: The trick to timestamp with authentication

kristof.teichel@ptb.de Mon, 07 December 2020 13:25 UTC

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From: kristof.teichel@ptb.de
To: Miroslav Lichvar <mlichvar@redhat.com>
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Subject: [Ntp] Antwort: Re: The trick to timestamp with authentication
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But having unauthenticated corrections just makes it easier for the attacker, because writing a false correction might be less effort than an actual delay attack.



-----"ntp" <ntp-bounces@ietf.org> schrieb: -----
An: ntp@ietf.org
Von: "Miroslav Lichvar"
Gesendet von: "ntp"
Datum: 07.12.2020 11:54
Betreff: Re: [Ntp] The trick to timestamp with authentication

On Fri, Dec 04, 2020 at 01:03:16AM +0000, Doug Arnold wrote:
> The ntp working group could decide ntpv5 can support on path corrections or security, but not both.  However, I suspect a lot of people would be disappointed.

Please don't forget that MITM attackers can delay packets and cause
larger errors in NTP measurements than unauthenticated corrections.
Not allowing switches to make unauthenticated corrections in
authenticated packets will not improve security.

--
Miroslav Lichvar

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