Re: [openpgp] Dealing with clock skew

Bill Frantz <frantz@pwpconsult.com> Sat, 16 November 2019 14:01 UTC

Return-Path: <frantz@pwpconsult.com>
X-Original-To: openpgp@ietfa.amsl.com
Delivered-To: openpgp@ietfa.amsl.com
Received: from localhost (localhost [127.0.0.1]) by ietfa.amsl.com (Postfix) with ESMTP id 6CB9C1200B4 for <openpgp@ietfa.amsl.com>; Sat, 16 Nov 2019 06:01:30 -0800 (PST)
X-Virus-Scanned: amavisd-new at amsl.com
X-Spam-Flag: NO
X-Spam-Score: -1.896
X-Spam-Level:
X-Spam-Status: No, score=-1.896 tagged_above=-999 required=5 tests=[BAYES_00=-1.9, RCVD_IN_DNSWL_NONE=-0.0001, RCVD_IN_MSPIKE_H3=0.001, RCVD_IN_MSPIKE_WL=0.001, SPF_HELO_NONE=0.001, SPF_NONE=0.001] 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 FDeQNfGt5Zfs for <openpgp@ietfa.amsl.com>; Sat, 16 Nov 2019 06:01:28 -0800 (PST)
Received: from elasmtp-mealy.atl.sa.earthlink.net (elasmtp-mealy.atl.sa.earthlink.net [209.86.89.69]) (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 D14D912001A for <openpgp@ietf.org>; Sat, 16 Nov 2019 06:01:28 -0800 (PST)
Received: from [66.31.15.242] (helo=Williams-MacBook-Pro.local) by elasmtp-mealy.atl.sa.earthlink.net with esmtpa (Exim 4) (envelope-from <frantz@pwpconsult.com>) id 1iVydj-000DV6-Em for openpgp@ietf.org; Sat, 16 Nov 2019 09:01:27 -0500
Date: Sat, 16 Nov 2019 09:01:27 -0500
From: Bill Frantz <frantz@pwpconsult.com>
To: openpgp@ietf.org
X-Priority: 3
In-Reply-To: <d424523b331984a39fdf1c87b7052a49.squirrel@mail2.ihtfp.org>
Message-ID: <r480Ps-10146i-8DAF5EBB5DBF4F29BFF6190D963B7385@Williams-MacBook-Pro.local>
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8; format=flowed
Content-Transfer-Encoding: quoted-printable
X-Mailer: Mailsmith 2.4.3 (480)
X-ELNK-Trace: 3a5e54fa03f1b3e21aa676d7e74259b7b3291a7d08dfec797604d40e6e4822429c694a1ebfa7a94c350badd9bab72f9c350badd9bab72f9c350badd9bab72f9c
X-Originating-IP: 66.31.15.242
Archived-At: <https://mailarchive.ietf.org/arch/msg/openpgp/6L7OjaqwoLl7HrbUTV_bhSUk0-8>
Subject: Re: [openpgp] Dealing with clock skew
X-BeenThere: openpgp@ietf.org
X-Mailman-Version: 2.1.29
Precedence: list
List-Id: "Ongoing discussion of OpenPGP issues." <openpgp.ietf.org>
List-Unsubscribe: <https://www.ietf.org/mailman/options/openpgp>, <mailto:openpgp-request@ietf.org?subject=unsubscribe>
List-Archive: <https://mailarchive.ietf.org/arch/browse/openpgp/>
List-Post: <mailto:openpgp@ietf.org>
List-Help: <mailto:openpgp-request@ietf.org?subject=help>
List-Subscribe: <https://www.ietf.org/mailman/listinfo/openpgp>, <mailto:openpgp-request@ietf.org?subject=subscribe>
X-List-Received-Date: Sat, 16 Nov 2019 14:01:31 -0000

On 11/15/19 at 6:38 AM, derek@ihtfp.com (Derek Atkins) wrote:

>If you are seeing 20-minute clock skew on a VM, then you should really set
>up ntp.

Amateur radio operators have a significant time skew problem 
when using certain digital modes (Key words: FT8, FT4, wsjt-x, 
and wsjt). To successfully complete a decode, the sender and 
receiver's clocks must be within 1/2 to 1 second of each other.

For the majority of operators, NTP is "good enough". Some 
operations, particularly those in locations without Internet 
access, use atomic clocks or GPS time.

Cheers - Bill

-----------------------------------------------------------------------
Bill Frantz        |Security, like correctness, is| Periwinkle
(408)356-8506      |not an add-on feature. - Attr-| 16345 
Englewood Ave
www.pwpconsult.com |ibuted to Andrew Tanenbaum    | Los Gatos, 
CA 95032