IETF Logo Mail Archive

Re: [art] Predictable Internet Time

"Manger, James" <James.H.Manger@team.telstra.com> Tue, 28 March 2017 22:56 UTC

Return-Path: <James.H.Manger@team.telstra.com>
X-Original-To: art@ietfa.amsl.com
Delivered-To: art@ietfa.amsl.com
Received: from localhost (localhost [127.0.0.1]) by ietfa.amsl.com (Postfix) with ESMTP id 5F803124D68 for <art@ietfa.amsl.com>; Tue, 28 Mar 2017 15:56:19 -0700 (PDT)
X-Virus-Scanned: amavisd-new at amsl.com
X-Spam-Flag: NO
X-Spam-Score: -2.6
X-Spam-Level:
X-Spam-Status: No, score=-2.6 tagged_above=-999 required=5 tests=[BAYES_00=-1.9, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, RCVD_IN_DNSWL_LOW=-0.7] autolearn=ham autolearn_force=no
Authentication-Results: ietfa.amsl.com (amavisd-new); dkim=pass (1024-bit key) header.d=teamtelstra.onmicrosoft.com
Received: from mail.ietf.org ([4.31.198.44]) by localhost (ietfa.amsl.com [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id Q3RTUip4IYxo for <art@ietfa.amsl.com>; Tue, 28 Mar 2017 15:56:17 -0700 (PDT)
Received: from ipxcno.tcif.telstra.com.au (ipxcno.tcif.telstra.com.au [203.35.82.208]) (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 4DC9E124234 for <art@ietf.org>; Tue, 28 Mar 2017 15:56:16 -0700 (PDT)
X-IronPort-AV: E=Sophos;i="5.36,238,1486386000"; d="scan'208";a="31816277"
Received: from unknown (HELO ipcbni.tcif.telstra.com.au) ([10.97.216.204]) by ipocni.tcif.telstra.com.au with ESMTP; 29 Mar 2017 09:56:14 +1100
X-IronPort-AV: E=McAfee;i="5800,7501,8481"; a="332857357"
Received: from wsmsg3704.srv.dir.telstra.com ([172.49.40.197]) by ipcbni.tcif.telstra.com.au with ESMTP; 29 Mar 2017 09:56:14 +1100
Received: from wsapp5585.srv.dir.telstra.com (10.75.3.67) by wsmsg3704.srv.dir.telstra.com (172.49.40.197) with Microsoft SMTP Server (TLS) id 8.3.485.1; Wed, 29 Mar 2017 09:56:14 +1100
Received: from wsapp5584.srv.dir.telstra.com (10.75.131.20) by wsapp5585.srv.dir.telstra.com (10.75.3.67) with Microsoft SMTP Server (TLS) id 15.0.1236.3; Wed, 29 Mar 2017 09:56:13 +1100
Received: from AUS01-SY3-obe.outbound.protection.outlook.com (10.172.101.126) by wsapp5584.srv.dir.telstra.com (10.75.131.20) with Microsoft SMTP Server (TLS) id 15.0.1236.3 via Frontend Transport; Wed, 29 Mar 2017 09:56:13 +1100
DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=teamtelstra.onmicrosoft.com; s=selector1-team-telstra-com; h=From:Date:Subject:Message-ID:Content-Type:MIME-Version; bh=d3Lm8/9zC1Cl48WZFg7YsZdVXQ9ZZEaoh2v6Crz5Fr4=; b=R37gdUhMKISmbMh1pak4JJ0kG6UIR6OFj9c3l5oS1+EFC5yN4qkr+wAHnLFXUY+/21cr512TCYgR/+7RgqjV+q5BmMhzN5sIZMGWqcTgjb6nstGwWccBTGmLM1qoNzFGUqrKHj6BXttq9Xo2iv15VJ53t55pyZrl/H2nGjgy0RU=
Received: from SYXPR01MB1615.ausprd01.prod.outlook.com (10.175.209.15) by SYXPR01MB1613.ausprd01.prod.outlook.com (10.175.209.13) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA256_P256) id 15.1.991.14; Tue, 28 Mar 2017 22:56:11 +0000
Received: from SYXPR01MB1615.ausprd01.prod.outlook.com ([10.175.209.15]) by SYXPR01MB1615.ausprd01.prod.outlook.com ([10.175.209.15]) with mapi id 15.01.0991.021; Tue, 28 Mar 2017 22:56:12 +0000
From: "Manger, James" <James.H.Manger@team.telstra.com>
To: "art@ietf.org" <art@ietf.org>, Joe Touch <touch@isi.edu>, Nico Williams <nico@cryptonector.com>
CC: Tony Finch <dot@dotat.at>, Philip Homburg <pch-ietf-art@u-1.phicoh.com>
Thread-Topic: [art] Predictable Internet Time
Thread-Index: AQHSp8x4+eWaPRFif0Gk8+C8dDs/KqGqXDSAgAA0TwCAAAYmAIAAATMAgAADwQCAAAHrAIAANdkg
Date: Tue, 28 Mar 2017 22:56:12 +0000
Message-ID: <SYXPR01MB161579A2B0F94F50B13C1232E5320@SYXPR01MB1615.ausprd01.prod.outlook.com>
References: <m1csrkh-0000GYC@stereo.hq.phicoh.net> <alpine.DEB.2.11.1703281603500.13590@grey.csi.cam.ac.uk> <809d2f85-0421-026b-f81d-6725e0548b6a@isi.edu> <20170328184301.GF7490@localhost> <8df1b619-d2c4-9830-a02f-372afa0077b3@isi.edu> <20170328190045.GG7490@localhost> <7096194a-aa8d-fb5a-dc9f-51670248bb88@isi.edu>
In-Reply-To: <7096194a-aa8d-fb5a-dc9f-51670248bb88@isi.edu>
Accept-Language: en-AU, en-US
Content-Language: en-US
X-MS-Has-Attach:
X-MS-TNEF-Correlator:
authentication-results: ietf.org; dkim=none (message not signed) header.d=none;ietf.org; dmarc=none action=none header.from=team.telstra.com;
x-originating-ip: [203.35.185.244]
x-microsoft-exchange-diagnostics: 1; SYXPR01MB1613; 7:mr+zHeX5eSdw7JxtR6KruVm1q0hwprDGy5P66Jfd7LwYQyTSyHEw5E/KNSYzzFlrykRVJIfqxexZ370g6o7n7uDroTGfsGqaektAilD3FnwPeue3Yez+iamwZ3QIOoVcmCFo84gMwyBGo8glarNb4CxPWAPhW3ciTvhkdT6WwlOm3hk5BC7eZ1/4dETuqr6TFf73CcaNBjihz4bsutRpdz8qZQIPzOQYxLgiAz3oIA/bIyXBID1eJ5DQJgiUuog65arTSO08QxtnM61p3C/JYPGqo6dr+MdyY0CiMTuiUHgE7JvqUEiHrA9oU1c+rBL7cUv3GGKEmlzFowG+AujVKA==; 20: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
x-ms-office365-filtering-correlation-id: de00051f-585d-4b6e-9205-08d4762da19b
x-microsoft-antispam: UriScan:; BCL:0; PCL:0; RULEID:(22001)(2017030254075)(201703131423067)(201703031133073); SRVR:SYXPR01MB1613;
x-microsoft-antispam-prvs: <SYXPR01MB1613AB100C4FC18B125C2694E5320@SYXPR01MB1613.ausprd01.prod.outlook.com>
x-exchange-antispam-report-test: UriScan:;
x-exchange-antispam-report-cfa-test: BCL:0; PCL:0; RULEID:(6040442)(2401047)(5005006)(8121501046)(3002001)(10201501046)(6041248)(20161123562025)(20161123564025)(20161123560025)(201703131423067)(201702281528067)(201703061421067)(201703061406067)(20161123558025)(20161123555025)(6072148); SRVR:SYXPR01MB1613; BCL:0; PCL:0; RULEID:; SRVR:SYXPR01MB1613;
x-forefront-prvs: 0260457E99
x-forefront-antispam-report: SFV:NSPM; SFS:(10019020)(6009001)(39450400003)(39410400002)(39850400002)(39400400002)(39840400002)(6436002)(5660300001)(189998001)(6506006)(33656002)(38730400002)(4326008)(229853002)(6246003)(3846002)(6116002)(2950100002)(42882006)(7696004)(102836003)(54356999)(25786009)(7736002)(76176999)(50986999)(77096006)(122556002)(2900100001)(305945005)(74316002)(53936002)(9686003)(8676002)(2501003)(3660700001)(93886004)(66066001)(2906002)(8936002)(86362001)(3280700002)(99286003)(55016002)(54906002); DIR:OUT; SFP:1102; SCL:1; SRVR:SYXPR01MB1613; H:SYXPR01MB1615.ausprd01.prod.outlook.com; FPR:; SPF:None; MLV:sfv; LANG:en;
spamdiagnosticoutput: 1:99
spamdiagnosticmetadata: NSPM
Content-Type: text/plain; charset="us-ascii"
Content-Transfer-Encoding: quoted-printable
MIME-Version: 1.0
X-MS-Exchange-CrossTenant-originalarrivaltime: 28 Mar 2017 22:56:12.2194 (UTC)
X-MS-Exchange-CrossTenant-fromentityheader: Hosted
X-MS-Exchange-CrossTenant-id: 49dfc6a3-5fb7-49f4-adea-c54e725bb854
X-MS-Exchange-Transport-CrossTenantHeadersStamped: SYXPR01MB1613
X-OriginatorOrg: team.telstra.com
Archived-At: <https://mailarchive.ietf.org/arch/msg/art/Cd9485Ns20BPnVOMd3AtKZ0P4O4>
Subject: Re: [art] Predictable Internet Time
X-BeenThere: art@ietf.org
X-Mailman-Version: 2.1.22
Precedence: list
List-Id: Applications and Real-Time Area Discussion <art.ietf.org>
List-Unsubscribe: <https://www.ietf.org/mailman/options/art>, <mailto:art-request@ietf.org?subject=unsubscribe>
List-Archive: <https://mailarchive.ietf.org/arch/browse/art/>
List-Post: <mailto:art@ietf.org>
List-Help: <mailto:art-request@ietf.org?subject=help>
List-Subscribe: <https://www.ietf.org/mailman/listinfo/art>, <mailto:art-request@ietf.org?subject=subscribe>
X-List-Received-Date: Tue, 28 Mar 2017 22:56:19 -0000

>> leap second smearing

> We certainly cannot even consider standardizing a conversion (even if that
> were our purview) between time scales that include smearing until there
> are smearing standards.

It looks like the most valuable IETF contribution would be standardizing one smearing scheme (& getting Google, Java, ... to agree to it).


> A key point in this doc is that smearing makes things horribly worse,
> not better in any way, except to delude users into thinking otherwise.

Given that a well-defined smearing scheme allows a simple and precise mapping to UTC, it is hard to see how that can be "horribly worse".

Smearing moves the complexity of solar-vs-atomic-vs-civic time and the resultant leap seconds to a place where a huge number of systems can correctly handle that complexity by "doing nothing", while systems that care if time intervals can be 0.001% wrong (if 24hr is the smear standard) can still be more precise by making well-defined adjustments.

--
James Manger

v2.23.0 | Report a Bug | By Email