[Ntp] Antw: Antw: Re: Antw: Re: Calls for Adoption -- NTP Extension Field drafts -- Four separate drafts

"Ulrich Windl" <Ulrich.Windl@rz.uni-regensburg.de> Mon, 02 September 2019 06:42 UTC

Return-Path: <Ulrich.Windl@rz.uni-regensburg.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 A81BC12002E for <ntp@ietfa.amsl.com>; Sun, 1 Sep 2019 23:42:55 -0700 (PDT)
X-Virus-Scanned: amavisd-new at amsl.com
X-Spam-Flag: NO
X-Spam-Score: -1.9
X-Spam-Level:
X-Spam-Status: No, score=-1.9 tagged_above=-999 required=5 tests=[BAYES_00=-1.9, SPF_HELO_NONE=0.001, SPF_PASS=-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 enU37Z10_Bqv for <ntp@ietfa.amsl.com>; Sun, 1 Sep 2019 23:42:54 -0700 (PDT)
Received: from mx4.uni-regensburg.de (mx4.uni-regensburg.de [IPv6:2001:638:a05:137:165:0:4:4e7a]) (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 DAB4E12006F for <ntp@ietf.org>; Sun, 1 Sep 2019 23:42:53 -0700 (PDT)
Received: from mx4.uni-regensburg.de (localhost [127.0.0.1]) by localhost (Postfix) with SMTP id 434186000061 for <ntp@ietf.org>; Mon, 2 Sep 2019 08:42:51 +0200 (CEST)
Received: from gwsmtp.uni-regensburg.de (gwsmtp1.uni-regensburg.de [132.199.5.51]) by mx4.uni-regensburg.de (Postfix) with ESMTP id 2C3DE6000060 for <ntp@ietf.org>; Mon, 2 Sep 2019 08:42:50 +0200 (CEST)
Received: from uni-regensburg-smtp1-MTA by gwsmtp.uni-regensburg.de with Novell_GroupWise; Mon, 02 Sep 2019 08:42:50 +0200
Message-Id: <5D6CB9E8020000A10003340A@gwsmtp.uni-regensburg.de>
X-Mailer: Novell GroupWise Internet Agent 18.1.1
Date: Mon, 02 Sep 2019 08:42:48 +0200
From: "Ulrich Windl" <Ulrich.Windl@rz.uni-regensburg.de>
To: "ntp@ietf.org" <ntp@ietf.org>,<magnus@rubidium.se>, "Ulrich Windl" <Ulrich.Windl@rz.uni-regensburg.de>
References: <1B4A56E7-16A6-4767-9268-BCF4BEB9A247@isoc.org> <BCA949D7-7D92-43A9-9766-573559A9FC70@meinberg.de> <5D66392D020000A100033273@gwsmtp.uni-regensburg.de> <8F6BAF5F-CC7B-47B9-90FD-BD20D6ABE845@meinberg.de> <20190828103752.GI24761@localhost> <3f4b55ca-02d9-a470-229b-40860866efbf@nwtime.org> <20190828111458.GJ24761@localhost> <e50112dd-f918-1135-74c8-a738ecb70b70@nwtime.org> <55867E75-9813-466B-8E57-0E157DE5AEB9@meinberg.de> <d308b5d4-3d6e-981b-3dfc-9d5938bad78d@rubidium.se> <5D6CB84E020000A100033405@gwsmtp.uni-regensburg.de>
In-Reply-To: <5D6CB84E020000A100033405@gwsmtp.uni-regensburg.de>
Mime-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit
Content-Disposition: inline
Archived-At: <https://mailarchive.ietf.org/arch/msg/ntp/OQGEvqqGh80zGERxtTSAkhQKD5k>
Subject: [Ntp] Antw: Antw: Re: Antw: Re: Calls for Adoption -- NTP Extension Field drafts -- Four separate drafts
X-BeenThere: ntp@ietf.org
X-Mailman-Version: 2.1.29
Precedence: list
List-Id: <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, 02 Sep 2019 06:42:56 -0000

>>> "Ulrich Windl" <Ulrich.Windl@rz.uni-regensburg.de> schrieb am 02.09.2019
um
08:35 in Nachricht <5D6CB84E020000A100033405@gwsmtp.uni-regensburg.de>de>:
>>>> Magnus Danielson <magnus@rubidium.se> schrieb am 28.08.2019 um 13:30 in
> Nachricht <d308b5d4-3d6e-981b-3dfc-9d5938bad78d@rubidium.se>se>:
>> I agree. If someone knocks on the door with v5 packets, reply in v5
>> form, if someone knocks on the door with v4 packets, reply in v4 form.
>> As people migrate to v5, they can start using all the benefits from it.
>> 
>> For loop‑protection, keeping a list of nodes from the source is a very
>> easy base condition to avoid routing loops, since as an announcement
> 
> But remember that a "note" is NOT "an IP address". With multi-homed hosts 

s/note/node/ # Sorry!

> you
> can have interesting synchronization loops... ;-)
> 
>> comes in, if none of the nodes in the list is oneself, you may use it,
>> where as if any of the nodes is oneself, a loop is for sure detected.
>> 
>> While the trace loop detection mechanism is sufficient in theory, it
>> does not completely solve all loop problems, as transient loops may
>> occur, but it at least avoids problems in the long term.
>> 
>> If I only had time to describe all the things I would do to enhance NTP,
>> it has a number of built‑in assumptions which is not useful or correct.
>> 
>> Cheers,
>> Magnus
>> 
>> On 2019‑08‑28 13:23, Heiko Gerstung wrote:
>>> Why not define a method in v5 that not only protects against degree 1
loops
> 
>> but maybe also against degree 2,3 or n? 
>>>
>>> This is what I meant when trying to explain that we should not stick to
the
> 
>> existing packet format with its shortcomings.
>>>
>>> Regards,
>>>    Heiko
>>>
>> 
>> _______________________________________________
>> 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