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Re: [Ntp] NTPv5: big picture

Miroslav Lichvar <mlichvar@redhat.com> Tue, 05 January 2021 08:54 UTC

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Date: Tue, 05 Jan 2021 09:54:23 +0100
From: Miroslav Lichvar <mlichvar@redhat.com>
To: Philip Prindeville <philipp@redfish-solutions.com>
Cc: Magnus Danielson <magnus@rubidium.se>, ntp@ietf.org
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Subject: Re: [Ntp] NTPv5: big picture
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On Mon, Jan 04, 2021 at 01:20:55PM -0700, Philip Prindeville wrote:
> PTP uses TAI.  It doesn’t seem to have been an impediment for them.  What am I missing?  And how did these “good technical reasons” not apply here?

PTP doesn't support TAI only. It supports TAI and an "arbitrary"
timescale. TAI is used for synchronization of hardware clocks, which
is the primary use case of PTP. If you wanted to synchronize a system
clock with PTP, the timestamps would typically be in the arbitrary
timescale (UTC).

To anyone proposing NTPv5 to support only a non-leaping timescale I'd
suggest them to try to implement it first.

-- 
Miroslav Lichvar

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