Re: Predictable Internet Time

Joe Touch <touch@isi.edu> Tue, 03 January 2017 23:22 UTC

Return-Path: <touch@isi.edu>
X-Original-To: ietf@ietfa.amsl.com
Delivered-To: ietf@ietfa.amsl.com
Received: from localhost (localhost [127.0.0.1]) by ietfa.amsl.com (Postfix) with ESMTP id EB5CA1294F5 for <ietf@ietfa.amsl.com>; Tue, 3 Jan 2017 15:22:36 -0800 (PST)
X-Virus-Scanned: amavisd-new at amsl.com
X-Spam-Flag: NO
X-Spam-Score: -9.999
X-Spam-Level:
X-Spam-Status: No, score=-9.999 tagged_above=-999 required=5 tests=[BAYES_00=-1.9, HTML_MESSAGE=0.001, RCVD_IN_DNSWL_HI=-5, RP_MATCHES_RCVD=-3.1] autolearn=ham autolearn_force=no
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 HNQMqO7jIjlw for <ietf@ietfa.amsl.com>; Tue, 3 Jan 2017 15:22:35 -0800 (PST)
Received: from boreas.isi.edu (boreas.isi.edu [128.9.160.161]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by ietfa.amsl.com (Postfix) with ESMTPS id C8E39129489 for <ietf@ietf.org>; Tue, 3 Jan 2017 15:22:35 -0800 (PST)
Received: from [128.9.160.211] (mul.isi.edu [128.9.160.211]) (authenticated bits=0) by boreas.isi.edu (8.13.8/8.13.8) with ESMTP id v03NLO6m004821 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES128-SHA bits=128 verify=NOT); Tue, 3 Jan 2017 15:21:24 -0800 (PST)
Subject: Re: Predictable Internet Time
To: Phillip Hallam-Baker <phill@hallambaker.com>, Tony Finch <dot@dotat.at>
References: <CAMm+LwgfQJ8aG5wB=d3fRbbeje3J9o7Z4_DCuP8DL88ouDeKzw@mail.gmail.com> <9F0F8841-BC1D-4C27-83EF-8F93F33FB021@puck.nether.net> <CAMm+Lwh5JMn+JxPB3Q3RKpeibckVSB2Fqm_RajcnU28OAx=jOw@mail.gmail.com> <1483474918.1346083.836313393.2699EBD5@webmail.messagingengine.com> <CAMm+LwjJDyCv2mBG8ob-njDj-4m5tr7jP6XAiEn1ME5NCYcpiQ@mail.gmail.com>
From: Joe Touch <touch@isi.edu>
Message-ID: <263de3ca-e2a2-c99f-1a9d-18e352c900ce@isi.edu>
Date: Tue, 3 Jan 2017 15:21:24 -0800
User-Agent: Mozilla/5.0 (Windows NT 10.0; WOW64; rv:45.0) Gecko/20100101 Thunderbird/45.5.1
MIME-Version: 1.0
In-Reply-To: <CAMm+LwjJDyCv2mBG8ob-njDj-4m5tr7jP6XAiEn1ME5NCYcpiQ@mail.gmail.com>
Content-Type: multipart/alternative; boundary="------------B8D8E894890BD22F3BCAC0C4"
X-ISI-4-43-8-MailScanner: Found to be clean
X-MailScanner-From: touch@isi.edu
Archived-At: <https://mailarchive.ietf.org/arch/msg/ietf/hEglbq6Ks0G3ULGFqBl6JfAhPik>
Cc: IETF Discussion Mailing List <ietf@ietf.org>, Jared Mauch <jared@puck.nether.net>
X-BeenThere: ietf@ietf.org
X-Mailman-Version: 2.1.17
Precedence: list
List-Id: IETF-Discussion <ietf.ietf.org>
List-Unsubscribe: <https://www.ietf.org/mailman/options/ietf>, <mailto:ietf-request@ietf.org?subject=unsubscribe>
List-Archive: <https://mailarchive.ietf.org/arch/browse/ietf/>
List-Post: <mailto:ietf@ietf.org>
List-Help: <mailto:ietf-request@ietf.org?subject=help>
List-Subscribe: <https://www.ietf.org/mailman/listinfo/ietf>, <mailto:ietf-request@ietf.org?subject=subscribe>
X-List-Received-Date: Tue, 03 Jan 2017 23:22:37 -0000


On 1/3/2017 1:57 PM, Phillip Hallam-Baker wrote:
> The reason I think the 20 hour current scheme is better is this:
>
> 1 	0.041666667 	0.05
> 2 	0.083333333 	0.1
> 3 	0.125 	0.15
> 4 	0.166666667 	0.2
> 5 	0.208333333 	0.25
> 6 	0.25 	0.3
>
>
> The second column is increments for the 24 hour change, the second for
> the 20 hour. As you can see, 24 hours means dealing with rounding.
> That is fine for Internet apps but an unnecessary source of error for
> scientific.

It depends on your representation. In base 10, the second column has
repeating digits but not the third.

In base 2, they both repeat so it really doesn't matter.

Joe