Re: [Ntp] Antw: [EXT] Re: Robert Wilton's Discuss on draft‑ietf‑ntp‑interleaved‑modes‑05: (with DISCUSS and COMMENT)

Miroslav Lichvar <mlichvar@redhat.com> Tue, 20 July 2021 12:10 UTC

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Date: Tue, 20 Jul 2021 14:10:07 +0200
From: Miroslav Lichvar <mlichvar@redhat.com>
To: Ulrich Windl <Ulrich.Windl@rz.uni-regensburg.de>
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On Tue, Jul 20, 2021 at 01:44:10PM +0200, Ulrich Windl wrote:
> Maybe NTPv5 can "lift" interleaved mode to a standard (with a fixed
> implementation, maybe).

Yes, that would be nice. My NTPv5 draft includes that. There
are only two differences between the two variants of the interleaved
mode:
- a flag is used to indicate the interleaved mode instead of checking
  equality between the origin timestamp and receive timestamp in the
  opposite directions
- a new 64-bit field is used as a server cookie instead of the receive
  timestamp

Of course, this doesn't change anything about compatibility with
existing NTPv4 implementations. There is no clean way to detect the
support.

-- 
Miroslav Lichvar