Re: [Ntp] Consensus call: NTPv5 and leap second smearing (vote to support clearly defined and UNAMBIGUOUSLY implemented smearing procedure)
kristof.teichel@ptb.de Mon, 10 July 2023 08:44 UTC
Return-Path: <kristof.teichel@ptb.de>
X-Original-To: ntp@ietfa.amsl.com
Delivered-To: ntp@ietfa.amsl.com
Received: from localhost (localhost [127.0.0.1]) by ietfa.amsl.com (Postfix) with ESMTP id 60A48C14CE5E for <ntp@ietfa.amsl.com>; Mon, 10 Jul 2023 01:44:51 -0700 (PDT)
X-Virus-Scanned: amavisd-new at amsl.com
X-Spam-Flag: NO
X-Spam-Score: -2.095
X-Spam-Level:
X-Spam-Status: No, score=-2.095 tagged_above=-999 required=5 tests=[BAYES_00=-1.9, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, HTML_MESSAGE=0.001, RCVD_IN_ZEN_BLOCKED_OPENDNS=0.001, SPF_HELO_NONE=0.001, SPF_PASS=-0.001, URIBL_BLOCKED=0.001, URIBL_DBL_BLOCKED_OPENDNS=0.001, URIBL_ZEN_BLOCKED_OPENDNS=0.001] autolearn=ham autolearn_force=no
Authentication-Results: ietfa.amsl.com (amavisd-new); dkim=pass (2048-bit key) header.d=ptb.de
Received: from mail.ietf.org ([50.223.129.194]) by localhost (ietfa.amsl.com [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id v7t_iNWi25oA for <ntp@ietfa.amsl.com>; Mon, 10 Jul 2023 01:44:47 -0700 (PDT)
Received: from mx1.bs.ptb.de (mx1.bs.ptb.de [192.53.103.120]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by ietfa.amsl.com (Postfix) with ESMTPS id 1B6CCC14CE4D for <ntp@ietf.org>; Mon, 10 Jul 2023 01:44:46 -0700 (PDT)
Received: from smtp-hub.bs.ptb.de (smtpint01.bs.ptb.de [141.25.87.32]) by mx1.bs.ptb.de with ESMTP id 36A8ii3L017487-36A8ii3N017487 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK) for <ntp@ietf.org>; Mon, 10 Jul 2023 10:44:44 +0200
In-Reply-To: <CAJm83bAFMVFycgvo_=dZtoXrEP8TsW0WbxmQcoi2eNzSdW1rPA@mail.gmail.com>
References: <29343948-036E-4514-8B42-689C19A61813@gmail.com> <CAJm83bAFMVFycgvo_=dZtoXrEP8TsW0WbxmQcoi2eNzSdW1rPA@mail.gmail.com>
To: NTP WG <ntp@ietf.org>
Cc: Dieter Sibold <dsibold.ietf@gmail.com>, Daniel Franke <dfoxfranke@gmail.com>
MIME-Version: 1.0
From: kristof.teichel@ptb.de
Message-ID: <OF767C37D0.D2022A60-ONC12589E8.002EE322-C12589E8.00300A45@ptb.de>
Date: Mon, 10 Jul 2023 10:44:43 +0200
Content-Type: multipart/alternative; boundary="=_alternative 00300A44C12589E8_="
X-FE-Last-Public-Client-IP: 141.25.87.32
X-FE-Policy-ID: 5:5:5:SYSTEM
DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; d=ptb.de; s=s1-ptbde; c=relaxed/relaxed; h=references:to:cc:mime-version:subject:from:message-id:date:content-type; bh=0ZTbFJnQssrB1chqBVqAUa4+yX4OumL/93wa1OTTxjM=; b=On9fKQQij5jGSg6l/qrwL3tcGTLNp7DT/PrfPwEAFW9QcMV9/zmamGpCemXj8qOS/RwtVWOsmQxf GUHiyuyyR9eJVCXR5GX7NRkb5enyuAuDH5UbwmfnOintD4es7e3tqUFEfOayKajGG0Th4vz6XJ5D 1Xdw+rO61Ym/p7NbPGA2wx62wMpfK/PdToodtN2V4qQbqIhufgP+dAROKb8AZJlAkcIiq8s01CND kkKTmmQe0C7TCbezn8/2HtX5YvWR8GruzTBMnhT/OMnxjmq/o8fsL5Equ96W6uJvAjHotBQ4l4pl S4oRe4thhWv6ekfnxnHwnwP4k1aFp8zvfiWP6w==
Archived-At: <https://mailarchive.ietf.org/arch/msg/ntp/XSEIJ_78go6FH33MAv2Ho80FeG4>
Subject: Re: [Ntp] Consensus call: NTPv5 and leap second smearing (vote to support clearly defined and UNAMBIGUOUSLY implemented smearing procedure)
X-BeenThere: ntp@ietf.org
X-Mailman-Version: 2.1.39
Precedence: list
List-Id: Network Time Protocol <ntp.ietf.org>
List-Unsubscribe: <https://www.ietf.org/mailman/options/ntp>, <mailto:ntp-request@ietf.org?subject=unsubscribe>
List-Archive: <https://mailarchive.ietf.org/arch/browse/ntp/>
List-Post: <mailto:ntp@ietf.org>
List-Help: <mailto:ntp-request@ietf.org?subject=help>
List-Subscribe: <https://www.ietf.org/mailman/listinfo/ntp>, <mailto:ntp-request@ietf.org?subject=subscribe>
X-List-Received-Date: Mon, 10 Jul 2023 08:44:51 -0000
I concur mostly with Daniel's view here. I do believe that we need to include "official" support for leap smearing, since prohibiting it is probably futile anyway. But it is not enough to set a flag to notify a client that a server is using smearing - not if we don't know how exactly it implements that smearing. What we need (if smearing is used) is a way to unambiguously convert and compare smeared time to non-smeared time. I like option 3 of Daniel's suggestions: encode UTC as TAI plus smearing event information and offset information - but I think a duration for the event might be necessary, I'm afraid not everyone might see noon-to-noon as the only acceptable interval. Besten Gruß / Kind regards, Kristof Teichel __________________________________________ Dr.-Ing. Kurt Kristof Teichel Physikalisch-Technische Bundesanstalt (PTB) Arbeitsgruppe 4.42 "Zeitübertragung" Bundesallee 100 38116 Braunschweig (Germany) Tel.: +49 (531) 592-4471 E-Mail: kristof.teichel@ptb.de __________________________________________ Von: "Daniel Franke" <dfoxfranke@gmail.com> An: "Dieter Sibold" <dsibold.ietf@gmail.com> Kopie: "NTP WG" <ntp@ietf.org> Datum: 02.07.2023 21:22 Betreff: Re: [Ntp] Consensus call: NTPv5 and leap second smearing Gesendet von: "ntp" <ntp-bounces@ietf.org> There are two things I care about: 1. The timestamp on the wire must be something that can be unambiguously converted to UTC. 2. The packet must contain sufficient information for the client to be able to apply a noon-to-noon smear if desired. The NTPv4 behavior of repeating during a leap second insertion is unacceptable, because this creates ambiguity. Any of the following would be equally acceptable to me: 1. Timestamps are UTC, represented using two fields: a day number, and time since midnight. Leap indicator bits MUST be set during precisely noon to noon . 2. Timestamps MUST be smeared linearly noon-to-noon in proximity to a leap event. The leap indicator MUST be set when and only when smearing is in progress. 3. Timestamps are TAI, and information elsewhere in the packet provides: a. The TAI time at which the last-announced leap event begins (may be past, present, or future) b. The direction of the event (insertion or deletion) c. The TAI-UTC offset at the completion of this event 1 and 2 are perfectly equivalent in what information they provide. 3 is more informative, and therefore nicer for the client but harder for the server, because it has to have the extra information available. On Wed, Jun 28, 2023 at 3:56?PM Dieter Sibold <dsibold.ietf@gmail.com> wrote: > > Dear all, > > at IETF 116 we decided to have two consensus calls regarding the content of the NTPv5 requirement draft. These are consensus calls that we would like to conduct to help progress the NTPv5 requirements document ( https://datatracker.ietf.org/doc/draft-ietf-ntp-ntpv5-requirements/). Both consensus calls will run until July 21st 2023 and will be discussed at the next NTP wg meeting at IETF 117 in San Francisco. > > The second consensus call: > > Regarding leap second smearing: > > Currently, the NTPv5 requirement draft states that NTP servers should not apply leap second smearing to transmitted timestamps. Shall NTPv5 support leap second smearing? If yes, shall the NTP server apply leap smearing to the transmitted timestamps or otherwise shall the client perform leap second smearing? > > > > Greetings > Karen and Dieter_______________________________________________ > ntp mailing list > ntp@ietf.org > https://www.ietf.org/mailman/listinfo/ntp _______________________________________________ ntp mailing list ntp@ietf.org https://www.ietf.org/mailman/listinfo/ntp
- [Ntp] Consensus call: NTPv5 and leap second smear… Dieter Sibold
- Re: [Ntp] Consensus call: NTPv5 and leap second s… Salz, Rich
- Re: [Ntp] Consensus call: NTPv5 and leap second s… Paul Gear
- Re: [Ntp] Consensus call: NTPv5 and leap second s… David Venhoek
- Re: [Ntp] [EXT] Re: Consensus call: NTPv5 and lea… Windl, Ulrich
- Re: [Ntp] Consensus call: NTPv5 and leap second s… Dave Hart
- Re: [Ntp] Consensus call: NTPv5 and leap second s… Steven Sommars
- Re: [Ntp] Consensus call: NTPv5 and leap second s… Harlan Stenn
- Re: [Ntp] Consensus call: NTPv5 and leap second s… Harlan Stenn
- Re: [Ntp] Consensus call: NTPv5 and leap second s… Danny Mayer
- Re: [Ntp] Consensus call: NTPv5 and leap second s… Daniel Franke
- Re: [Ntp] Consensus call: NTPv5 and leap second s… Harlan Stenn
- Re: [Ntp] Consensus call: NTPv5 and leap second s… James Browning
- Re: [Ntp] Consensus call: NTPv5 and leap second s… Harlan Stenn
- Re: [Ntp] Consensus call: NTPv5 and leap second s… Danny Mayer
- Re: [Ntp] Consensus call: NTPv5 and leap second s… Martin Burnicki
- Re: [Ntp] Consensus call: NTPv5 and leap second s… Dieter Sibold
- Re: [Ntp] Consensus call: NTPv5 and leap second s… Doug Arnold
- Re: [Ntp] Consensus call: NTPv5 and leap second s… Denis Reilly
- Re: [Ntp] Consensus call: NTPv5 and leap second s… James
- Re: [Ntp] Consensus call: NTPv5 and leap second s… Martin Burnicki
- Re: [Ntp] Consensus call: NTPv5 and leap second s… kristof.teichel
- Re: [Ntp] Consensus call: NTPv5 and leap second s… martin.langer
- Re: [Ntp] Consensus call: NTPv5 and leap second s… Miroslav Lichvar
- Re: [Ntp] [EXTERNAL] Re: Consensus call: NTPv5 an… Denis Reilly
- Re: [Ntp] Consensus call: NTPv5 and leap second s… Daniel Franke
- [Ntp] Antwort: Re: Consensus call: NTPv5 and leap… kristof.teichel
- Re: [Ntp] Consensus call: NTPv5 and leap second s… Warner Losh
- Re: [Ntp] Consensus call: NTPv5 and leap second s… Steve Allen
- Re: [Ntp] Consensus call: NTPv5 and leap second s… Watson Ladd
- Re: [Ntp] Consensus call: NTPv5 and leap second s… Harlan Stenn
- Re: [Ntp] Consensus call: NTPv5 and leap second s… Dave Hart
- Re: [Ntp] [EXT] Re: Consensus call: NTPv5 and lea… Windl, Ulrich
- Re: [Ntp] Consensus call: NTPv5 and leap second s… Martin Burnicki
- Re: [Ntp] [EXTERNAL] Re: Consensus call: NTPv5 an… Martin Burnicki
- Re: [Ntp] Consensus call: NTPv5 and leap second s… Martin Burnicki
- Re: [Ntp] [EXTERNAL] Re: Consensus call: NTPv5 an… Denis Reilly
- Re: [Ntp] [EXT] Re: Consensus call: NTPv5 and lea… Martin Burnicki
- Re: [Ntp] [EXTERNAL] Re: Consensus call: NTPv5 an… Martin Burnicki
- Re: [Ntp] [EXT] Re: Re: Consensus call: NTPv5 and… Windl, Ulrich
- Re: [Ntp] [EXT] Re: Consensus call: NTPv5 and lea… Windl, Ulrich
- Re: [Ntp] [EXT] Re: Consensus call: NTPv5 and lea… Windl, Ulrich
- Re: [Ntp] [EXT] Re: [EXTERNAL] Re: Consensus call… Windl, Ulrich
- Re: [Ntp] [EXT] Re: Re: Consensus call: NTPv5 and… Harlan Stenn
- Re: [Ntp] [EXT] Re: Re: Re: Consensus call: NTPv5… Windl, Ulrich
- Re: [Ntp] [EXT] Re: Consensus call: NTPv5 and lea… Martin Burnicki
- Re: [Ntp] [EXT] Re: Re: Re: Consensus call: NTPv5… Harlan Stenn
- Re: [Ntp] [EXT] Re: Consensus call: NTPv5 and lea… Martin Burnicki
- Re: [Ntp] [EXT] Re: Re: Consensus call: NTPv5 and… Martin Burnicki
- Re: [Ntp] [EXT] Re: Re: Re: Re: Consensus call: N… Windl, Ulrich
- Re: [Ntp] [EXT] Re: [EXTERNAL] Re: Consensus call… Martin Burnicki
- Re: [Ntp] [EXT] Re: Re: Re: Consensus call: NTPv5… Windl, Ulrich
- Re: [Ntp] [EXT] Re: Re: Re: Re: Consensus call: N… Martin Burnicki
- Re: [Ntp] [EXT] Re: Re: Re: Re: Consensus call: N… Harlan Stenn
- Re: [Ntp] [EXT] Re: Re: Re: Consensus call: NTPv5… Harlan Stenn
- Re: [Ntp] [EXT] Re: Re: Re: Re: Re: Consensus cal… Windl, Ulrich
- Re: [Ntp] [EXTERNAL] Re: [EXT] Re: Consensus call… Denis Reilly
- Re: [Ntp] Consensus call: NTPv5 and leap second s… Miroslav Lichvar
- Re: [Ntp] [EXTERNAL] Re: [EXT] Re: Consensus call… Martin Burnicki
- Re: [Ntp] Consensus call: NTPv5 and leap second s… Daniel Franke
- Re: [Ntp] [EXT] Re: Consensus call: NTPv5 and lea… Warner Losh
- Re: [Ntp] [EXT] Re: Consensus call: NTPv5 and lea… Warner Losh
- Re: [Ntp] [EXT] Re: [EXTERNAL] Re: Re: Consensus … Windl, Ulrich
- Re: [Ntp] [EXT] Re: Re: Consensus call: NTPv5 and… Windl, Ulrich
- Re: [Ntp] Consensus call: NTPv5 and leap second s… Miroslav Lichvar
- Re: [Ntp] [EXT] Re: Consensus call: NTPv5 and lea… Martin Burnicki
- Re: [Ntp] [EXT] Re: [EXTERNAL] Re: Re: Consensus … Martin Burnicki
- Re: [Ntp] [EXTERNAL] Re: [EXT] Re: Consensus call… Danny Mayer
- Re: [Ntp] [EXT] Re: [EXTERNAL] Re: Re: Consensus … Windl, Ulrich
- Re: [Ntp] [EXTERNAL] Re: [EXT] Re: Consensus call… Martin Burnicki
- Re: [Ntp] [EXT] Re: [EXTERNAL] Re: Re: Consensus … Harlan Stenn
- Re: [Ntp] [EXT] Re: [EXTERNAL] Re: Re: Consensus … Martin Burnicki
- Re: [Ntp] [EXT] Re: Re: [EXTERNAL] Re: Re: Consen… Windl, Ulrich
- Re: [Ntp] [EXT] Re: Re: [EXTERNAL] Re: Re: Consen… Martin Burnicki
- Re: [Ntp] [EXT] Re: Re: [EXTERNAL] Re: Re: Consen… Windl, Ulrich
- Re: [Ntp] [EXT] Re: Re: [EXTERNAL] Re: Re: Consen… Martin Burnicki