Re: [Ntp] Antw: Re: Calls for Adoption -- NTP Extension Field drafts -- Four separate drafts

Miroslav Lichvar <mlichvar@redhat.com> Mon, 02 September 2019 07:59 UTC

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Date: Mon, 2 Sep 2019 09:59:44 +0200
From: Miroslav Lichvar <mlichvar@redhat.com>
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Subject: Re: [Ntp] Antw: Re: Calls for Adoption -- NTP Extension Field drafts -- Four separate drafts
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On Wed, Aug 28, 2019 at 01:30:33PM +0200, Magnus Danielson wrote:
> I agree. If someone knocks on the door with v5 packets, reply in v5
> form, if someone knocks on the door with v4 packets, reply in v4 form.
> As people migrate to v5, they can start using all the benefits from it.
> 
> For loop-protection, keeping a list of nodes from the source is a very
> easy base condition to avoid routing loops, since as an announcement
> comes in, if none of the nodes in the list is oneself, you may use it,
> where as if any of the nodes is oneself, a loop is for sure detected.

NTP clients can be synchronized to multiple sources at the same time,
so it's not just a list - it's a graph. In any case, this probably
requires a new extension field and it could work equally well in both
NTPv4 and NTPv5. I was hoping the suggested-refid EF could evolve in
that.

> If I only had time to describe all the things I would do to enhance NTP,
> it has a number of built-in assumptions which is not useful or correct.

Well, maybe we could start with a list of issues of NTPv4 to get an
idea of what needs to be fixed in NTPv5 (and what just needs a new
extension field)? I have a few items. I think we could use the NTP WG
wiki.

-- 
Miroslav Lichvar