Re: [Ntp] Antwort: Re: The trick to timestamp with authentication
Miroslav Lichvar <mlichvar@redhat.com> Mon, 07 December 2020 13:50 UTC
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Date: Mon, 07 Dec 2020 14:50:01 +0100
From: Miroslav Lichvar <mlichvar@redhat.com>
To: kristof.teichel@ptb.de
Cc: ntp@ietf.org
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References: <20201207105406.GF2352378@localhost> <doug.arnold@meinberg-usa.com> <BEF7C4D9-81CD-42AD-BA06-433D45C0DCD1@meinberg-usa.com> <20201203233634.15F7940605C@ip-64-139-1-69.sjc.megapath.net> <12C6B0FF-8C20-4363-AF41-FDF98B2D8072@meinberg-usa.com> <OF24F50CB5.1E226959-ONC1258637.0049B781-C1258637.0049B784@ptb.de>
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Subject: Re: [Ntp] Antwort: Re: The trick to timestamp with authentication
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On Mon, Dec 07, 2020 at 02:25:11PM +0100, kristof.teichel@ptb.de wrote: > 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. I'd say it is the opposite. Delaying a packet is not that difficult. For example, you can generate traffic in order to increase queueing delays in switches/routers. In a MITM attack you need to prevent the original packet sent by the client or server reaching the other host. If you can do that, is it easier to sent a modified packet than just waiting a bit before sending the captured packet unmodified? I don't think there is a big difference. -- Miroslav Lichvar
- [Ntp] The trick to timestamp with authentication Watson Ladd
- Re: [Ntp] The trick to timestamp with authenticat… Hal Murray
- Re: [Ntp] The trick to timestamp with authenticat… Doug Arnold
- Re: [Ntp] The trick to timestamp with authenticat… Hal Murray
- Re: [Ntp] The trick to timestamp with authenticat… Doug Arnold
- Re: [Ntp] The trick to timestamp with authenticat… James
- Re: [Ntp] The trick to timestamp with authenticat… Dieter Sibold
- Re: [Ntp] The trick to timestamp with authenticat… Miroslav Lichvar
- [Ntp] Antwort: Re: The trick to timestamp with au… kristof.teichel
- Re: [Ntp] Antwort: Re: The trick to timestamp wit… Miroslav Lichvar
- Re: [Ntp] Antwort: Re: The trick to timestamp wit… Dieter Sibold
- Re: [Ntp] Antwort: Re: The trick to timestamp wit… Philip Prindeville
- Re: [Ntp] Antwort: Re: The trick to timestamp wit… Watson Ladd