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Re: [Ntp] Comments on draft-langer-ntp-nts-for-ptp

Miroslav Lichvar <mlichvar@redhat.com> Mon, 08 March 2021 10:37 UTC

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Date: Mon, 08 Mar 2021 11:36:53 +0100
From: Miroslav Lichvar <mlichvar@redhat.com>
To: Watson Ladd <watsonbladd@gmail.com>
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Subject: Re: [Ntp] Comments on draft-langer-ntp-nts-for-ptp
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On Fri, Mar 05, 2021 at 11:55:22AM -0800, Watson Ladd wrote:
> I think this is an important draft that covers a real usecase, but
> should try to break the flow of NTS a bit less. I hope these comments
> are useful.

There might be a more general question that needs to be answered
first. What exactly it means for "NTS" to be applied to a time
synchronization protocol? IIRC we originally had a general NTS
draft and a separate NTS-for-NTP draft.

PTP, like the NTP broadcast mode, cannot be secured to the same extent
as the NTP client-server mode. We had some attempts and they failed.

If I understand it correctly, this draft is not trying to apply the
NTS-NTP principles to PTP. That's not possible. It just reuses the
NTS-KE protocol for its own security protocol. I think that's
perfectly fine as long as there is no confusion about the NTS part.

-- 
Miroslav Lichvar

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