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

Miroslav Lichvar <mlichvar@redhat.com> Wed, 28 August 2019 12:52 UTC

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Date: Wed, 28 Aug 2019 14:52:11 +0200
From: Miroslav Lichvar <mlichvar@redhat.com>
To: ntp@ietf.org
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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 01:08:46PM +0200, Heiko Gerstung wrote:
> Any implementation that wants to be v4/v5 compatible can easily deal with two different packet header formats IMHO. Handling this in the right way will not remotely add as much complexity as all the other v5 changes will cause. Think about the added complexity when someone has to implement the RefID handling as described in that draft, compared to just having an additional field in the packet that indicates there is a leap second smear going on, or there is a specific ID that you want clients to use when they refer to your server in their RefID field. 

Only servers care about refids.

Consider how much code will need to be written or changed to add an
NTPv5 support to existing implementations.

Most clients are extremely simple. They send a request with almost all
fields set to zero and ignore most fields in the response. Ideally, I
think upgrading such a client to NTPv5 would consist of just changing
the version in the request and accepting the version in the response
No other changes required. A single codepath works with NTPv2, NTPv3,
NTPv4, NTPv5.

-- 
Miroslav Lichvar