Re: [Ntp] Antw: Re: Calls for Adoption -- NTP Extension Field drafts -- Four separate drafts
Miroslav Lichvar <mlichvar@redhat.com> Wed, 28 August 2019 10:37 UTC
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Date: Wed, 28 Aug 2019 12:37:52 +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 12:07:53PM +0200, Heiko Gerstung wrote: > Regarding backwards compatibility of NTPv5: I think it would be no problem to change the NTP packet format if there are requirements we want to meet that can be fulfilled more efficiently with a changed packet header. Any implementation that ignores the version field deserves whatever happens to it and, since a client mode packet contains the version number, an NTP server would most probably have to reply to a v4 client request with a v4 server response anyway. Only if an implementation sends a request with version=5 and then tries to decode the response based on a v4 packet format there will be a problem. And again, implementations doing this should go down in flames anyway IMHO. I think a good reason to keep v5 mostly compatible with v4, similarly to how previous versions were compatible with one another, would be avoiding extra complexity in both server and client implementations. My suggestion would be to keep the NTP header 48 octets long and change only two fields: the refid and reference timestamp. They are ignored by current servers and most clients. That gives us 12 octets of contiguous space in the header to work with. That's plenty for the timescale negotiation and other metadata. Longer fields should be in extension fields. No MACs allowed. FWIW, I'm willing to help with the NTPv5 specification if people are considering to start working on that. -- Miroslav Lichvar
- [Ntp] Calls for Adoption -- NTP Extension Field d… Karen O'Donoghue
- Re: [Ntp] Calls for Adoption -- NTP Extension Fie… Heiko Gerstung
- [Ntp] Antw: Re: Calls for Adoption -- NTP Extensi… Ulrich Windl
- Re: [Ntp] Calls for Adoption -- NTP Extension Fie… tglassey@earthlink.net
- Re: [Ntp] Antw: Re: Calls for Adoption -- NTP Ext… Heiko Gerstung
- Re: [Ntp] Antw: Re: Calls for Adoption -- NTP Ext… Miroslav Lichvar
- Re: [Ntp] Antw: Re: Calls for Adoption -- NTP Ext… Miroslav Lichvar
- Re: [Ntp] Antw: Re: Calls for Adoption -- NTP Ext… Harlan Stenn
- Re: [Ntp] Antw: Re: Calls for Adoption -- NTP Ext… Heiko Gerstung
- Re: [Ntp] Antw: Re: Calls for Adoption -- NTP Ext… Miroslav Lichvar
- Re: [Ntp] Antw: Re: Calls for Adoption -- NTP Ext… Harlan Stenn
- Re: [Ntp] Antw: Re: Calls for Adoption -- NTP Ext… Heiko Gerstung
- Re: [Ntp] Antw: Re: Calls for Adoption -- NTP Ext… Miroslav Lichvar
- Re: [Ntp] Antw: Re: Calls for Adoption -- NTP Ext… Harlan Stenn
- Re: [Ntp] Antw: Re: Calls for Adoption -- NTP Ext… Harlan Stenn
- Re: [Ntp] Antw: Re: Calls for Adoption -- NTP Ext… Heiko Gerstung
- [Ntp] Antw: Re: Antw: Re: Calls for Adoption -- N… Ulrich Windl
- Re: [Ntp] Antw: Re: Calls for Adoption -- NTP Ext… Miroslav Lichvar
- Re: [Ntp] Calls for Adoption -- NTP Extension Fie… Daniel Franke
- Re: [Ntp] Antw: Re: Calls for Adoption -- NTP Ext… Heiko Gerstung
- Re: [Ntp] Antw: Re: Antw: Re: Calls for Adoption … Heiko Gerstung
- Re: [Ntp] Calls for Adoption -- NTP Extension Fie… Watson Ladd
- Re: [Ntp] Calls for Adoption -- NTP Extension Fie… Salz, Rich
- [Ntp] Antw: Re: Antw: Re: Calls for Adoption -- N… Ulrich Windl
- Re: [Ntp] Antw: Re: Calls for Adoption -- NTP Ext… Dieter Sibold
- Re: [Ntp] Calls for Adoption -- NTP Extension Fie… kristof.teichel
- Re: [Ntp] Antw: Re: Calls for Adoption -- NTP Ext… Magnus Danielson
- [Ntp] Antw: Re: Antw: Re: Calls for Adoption -- N… Ulrich Windl
- [Ntp] Antw: Antw: Re: Antw: Re: Calls for Adoptio… Ulrich Windl
- Re: [Ntp] Antw: Re: Calls for Adoption -- NTP Ext… Miroslav Lichvar
- Re: [Ntp] Antw: Re: Antw: Re: Calls for Adoption … Heiko Gerstung
- Re: [Ntp] Antw: Re: Antw: Re: Calls for Adoption … Hal Murray
- Re: [Ntp] Antw: Re: Antw: Re: Calls for Adoption … Miroslav Lichvar
- [Ntp] Antw: Re: Antw: Re: Calls for Adoption -- N… Ulrich Windl
- Re: [Ntp] Antw: Re: Antw: Re: Calls for Adoption … Harlan Stenn
- [Ntp] Antw: Re: Antw: Re: Antw: Re: Calls for Ado… Ulrich Windl
- [Ntp] Antw: Re: Antw: Re: Antw: Re: Calls for Ado… Ulrich Windl
- Re: [Ntp] Antw: Re: Antw: Re: Calls for Adoption … Heiko Gerstung
- Re: [Ntp] Antw: Re: Calls for Adoption -- NTP Ext… Harlan Stenn
- [Ntp] Antw: Re: Antw: Re: Antw: Re: Calls for Ado… Ulrich Windl
- Re: [Ntp] Antw: Re: Calls for Adoption -- NTP Ext… Heiko Gerstung
- Re: [Ntp] Calls for Adoption -- NTP Extension Fie… Miroslav Lichvar
- Re: [Ntp] Antw: Re: Calls for Adoption -- NTP Ext… Harlan Stenn
- Re: [Ntp] Antw: Re: Calls for Adoption -- NTP Ext… Magnus Danielson
- Re: [Ntp] Antw: Re: Antw: Re: Antw: Re: Calls for… Harlan Stenn
- Re: [Ntp] Antw: Re: Calls for Adoption -- NTP Ext… Heiko Gerstung
- Re: [Ntp] Antw: Re: Calls for Adoption -- NTP Ext… Harlan Stenn
- Re: [Ntp] Antw: Re: Calls for Adoption -- NTP Ext… Harlan Stenn
- Re: [Ntp] Antw: Re: Calls for Adoption -- NTP Ext… Daniel Franke
- Re: [Ntp] Antw: Re: Calls for Adoption -- NTP Ext… Miroslav Lichvar
- Re: [Ntp] Antw: Re: Calls for Adoption -- NTP Ext… Harlan Stenn
- Re: [Ntp] Antw: Re: Calls for Adoption -- NTP Ext… Heiko Gerstung
- Re: [Ntp] Antw: Re: Calls for Adoption -- NTP Ext… Hal Murray
- Re: [Ntp] Antw: Re: Calls for Adoption -- NTP Ext… Heiko Gerstung
- Re: [Ntp] Antw: Re: Calls for Adoption -- NTP Ext… Harlan Stenn
- Re: [Ntp] Antw: Re: Calls for Adoption -- NTP Ext… Harlan Stenn
- Re: [Ntp] Antw: Re: Calls for Adoption -- NTP Ext… Heiko Gerstung
- Re: [Ntp] Antw: Re: Antw: Re: Calls for Adoption … Hal Murray
- Re: [Ntp] Antw: Re: Antw: Re: Calls for Adoption … Miroslav Lichvar
- Re: [Ntp] Antw: Re: Antw: Re: Calls for Adoption … Heiko Gerstung
- [Ntp] Antw: Re: Antw: Re: Antw: Re: Calls for Ado… Ulrich Windl
- [Ntp] Antw: Re: Antw: Re: Antw: Re: Calls for Ado… Ulrich Windl
- Re: [Ntp] Antw: Re: Antw: Re: Antw: Re: Calls for… Watson Ladd
- Re: [Ntp] Antw: Re: Calls for Adoption -- NTP Ext… Salz, Rich
- Re: [Ntp] Antw: Re: Calls for Adoption -- NTP Ext… Daniel Franke
- Re: [Ntp] Antw: Re: Calls for Adoption -- NTP Ext… Salz, Rich
- Re: [Ntp] Antw: Re: Calls for Adoption -- NTP Ext… Daniel Franke
- Re: [Ntp] Antw: Re: Calls for Adoption -- NTP Ext… Salz, Rich
- Re: [Ntp] Antw: Re: Calls for Adoption -- NTP Ext… Salz, Rich
- [Ntp] NTP errors Hal Murray
- Re: [Ntp] Calls for Adoption -- NTP Extension Fie… Harlan Stenn
- [Ntp] Antw: Re: Antw: Re: Calls for Adoption -- N… Ulrich Windl
- Re: [Ntp] Antw: Re: Antw: Re: Calls for Adoption … Watson Ladd
- Re: [Ntp] Antw: Re: Antw: Re: Calls for Adoption … Hal Murray
- [Ntp] Antw: Re: Antw: Re: Antw: Re: Calls for Ado… Ulrich Windl
- Re: [Ntp] Antw: Re: Calls for Adoption -- NTP Ext… Miroslav Lichvar
- Re: [Ntp] Antw: Re: Calls for Adoption -- NTP Ext… Hal Murray
- Re: [Ntp] Antw: Re: Calls for Adoption -- NTP Ext… Miroslav Lichvar
- Re: [Ntp] Calls for Adoption -- NTP Extension Fie… Fernando Gont
- Re: [Ntp] Antw: Re: Calls for Adoption -- NTP Ext… Miroslav Lichvar
- [Ntp] Antw: Re: Antw: Re: Calls for Adoption -- N… Ulrich Windl
- Re: [Ntp] Antw: Re: Antw: Re: Calls for Adoption … Harlan Stenn
- Re: [Ntp] Antw: Re: Antw: Re: Calls for Adoption … Miroslav Lichvar
- [Ntp] Antw: Re: Antw: Re: Antw: Re: Calls for Ado… Ulrich Windl
- Re: [Ntp] Antw: Re: Antw: Re: Antw: Re: Calls for… Watson Ladd
- Re: [Ntp] Antw: Re: Antw: Re: Calls for Adoption … Hal Murray
- Re: [Ntp] Antw: Re: Antw: Re: Calls for Adoption … Mark Atwood
- Re: [Ntp] Antw: Re: Antw: Re: Calls for Adoption … Steven Sommars
- [Ntp] Antw: Re: Antw: Re: Antw: Re: Calls for Ado… Ulrich Windl