Re: [netmod] New Version Notification for draft-verdt-netmod-yang-versioning-reqs-01.txt

Juergen Schoenwaelder <j.schoenwaelder@jacobs-university.de> Fri, 09 November 2018 15:13 UTC

Return-Path: <j.schoenwaelder@jacobs-university.de>
X-Original-To: netmod@ietfa.amsl.com
Delivered-To: netmod@ietfa.amsl.com
Received: from localhost (localhost [127.0.0.1]) by ietfa.amsl.com (Postfix) with ESMTP id 4E60A130E2D for <netmod@ietfa.amsl.com>; Fri, 9 Nov 2018 07:13:54 -0800 (PST)
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, RCVD_IN_DNSWL_NONE=-0.0001] 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 boeymN5QUK6T for <netmod@ietfa.amsl.com>; Fri, 9 Nov 2018 07:13:51 -0800 (PST)
Received: from atlas5.jacobs-university.de (atlas5.jacobs-university.de [212.201.44.20]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by ietfa.amsl.com (Postfix) with ESMTPS id 25433130EB8 for <netmod@ietf.org>; Fri, 9 Nov 2018 07:13:51 -0800 (PST)
Received: from localhost (demetrius5.irc-it.jacobs-university.de [10.70.0.222]) by atlas5.jacobs-university.de (Postfix) with ESMTP id BD98DE1F; Fri, 9 Nov 2018 16:13:49 +0100 (CET)
X-Virus-Scanned: amavisd-new at jacobs-university.de
Received: from atlas5.jacobs-university.de ([10.70.0.217]) by localhost (demetrius5.jacobs-university.de [10.70.0.222]) (amavisd-new, port 10032) with ESMTP id pJOCkE8emoih; Fri, 9 Nov 2018 16:13:48 +0100 (CET)
Received: from hermes.jacobs-university.de (hermes.jacobs-university.de [212.201.44.23]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (Client CN "hermes.jacobs-university.de", Issuer "Jacobs University CA - G01" (verified OK)) by atlas5.jacobs-university.de (Postfix) with ESMTPS; Fri, 9 Nov 2018 16:13:49 +0100 (CET)
Received: from localhost (demetrius2.jacobs-university.de [212.201.44.47]) by hermes.jacobs-university.de (Postfix) with ESMTP id A736F2003D; Fri, 9 Nov 2018 16:13:49 +0100 (CET)
X-Virus-Scanned: amavisd-new at jacobs-university.de
Received: from hermes.jacobs-university.de ([212.201.44.23]) by localhost (demetrius2.jacobs-university.de [212.201.44.32]) (amavisd-new, port 10024) with ESMTP id raEwQMPEvVz1; Fri, 9 Nov 2018 16:13:49 +0100 (CET)
Received: from exchange.jacobs-university.de (SXCHMB02.jacobs.jacobs-university.de [10.70.0.121]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (Client CN "exchange.jacobs-university.de", Issuer "DFN-Verein Global Issuing CA" (verified OK)) by hermes.jacobs-university.de (Postfix) with ESMTPS id 29B4F2003C; Fri, 9 Nov 2018 16:13:49 +0100 (CET)
Received: from anna.localdomain (10.50.218.117) by sxchmb03.jacobs.jacobs-university.de (10.70.0.155) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.1.1591.10; Fri, 9 Nov 2018 16:13:48 +0100
Received: by anna.localdomain (Postfix, from userid 501) id E30AD3003CB416; Fri, 9 Nov 2018 16:13:47 +0100 (CET)
Date: Fri, 09 Nov 2018 16:13:47 +0100
From: Juergen Schoenwaelder <j.schoenwaelder@jacobs-university.de>
To: Martin Bjorklund <mbj@tail-f.com>
CC: andy@yumaworks.com, netmod@ietf.org
Message-ID: <20181109151347.3xms2cty6hxyl232@anna.jacobs.jacobs-university.de>
Reply-To: Juergen Schoenwaelder <j.schoenwaelder@jacobs-university.de>
Mail-Followup-To: Martin Bjorklund <mbj@tail-f.com>, andy@yumaworks.com, netmod@ietf.org
References: <20181027211355.ppu7wavjcq2butc4@anna.jacobs.jacobs-university.de> <20181108.224220.1513800936571555652.mbj@tail-f.com> <20181109081557.kzalxvnsk2k2fycm@anna.jacobs.jacobs-university.de> <20181109.143729.1869485019013831956.mbj@tail-f.com>
MIME-Version: 1.0
Content-Type: text/plain; charset="us-ascii"
Content-Disposition: inline
In-Reply-To: <20181109.143729.1869485019013831956.mbj@tail-f.com>
User-Agent: NeoMutt/20180716
X-ClientProxiedBy: SXCHMB02.jacobs.jacobs-university.de (10.70.0.121) To sxchmb03.jacobs.jacobs-university.de (10.70.0.155)
Archived-At: <https://mailarchive.ietf.org/arch/msg/netmod/Zqip8tyxn_N40VdZ1CQ4cKASYOM>
Subject: Re: [netmod] New Version Notification for draft-verdt-netmod-yang-versioning-reqs-01.txt
X-BeenThere: netmod@ietf.org
X-Mailman-Version: 2.1.29
Precedence: list
List-Id: NETMOD WG list <netmod.ietf.org>
List-Unsubscribe: <https://www.ietf.org/mailman/options/netmod>, <mailto:netmod-request@ietf.org?subject=unsubscribe>
List-Archive: <https://mailarchive.ietf.org/arch/browse/netmod/>
List-Post: <mailto:netmod@ietf.org>
List-Help: <mailto:netmod-request@ietf.org?subject=help>
List-Subscribe: <https://www.ietf.org/mailman/listinfo/netmod>, <mailto:netmod-request@ietf.org?subject=subscribe>
X-List-Received-Date: Fri, 09 Nov 2018 15:14:00 -0000

On Fri, Nov 09, 2018 at 02:37:29PM +0100, Martin Bjorklund wrote:
> 
> > I think we need to distinguish between the agreement on the
> > requirement, namely that a server should be able to provide support
> > for an old and a new definition, and agreement on the solution.
> > 
> > Do you disagree with the requirement? Or do you disagree with the
> > consequences of implementing multiple versions of the same module
> > for some of the proposed new versioning schemes? Or both?
> 
> I do not agree with the requirement that a server MUST be able to
> support multiple revisions of the same module, which is how I
> interpret 3.2.  If this is not the intention of 3.2, maybe it can be
> clarified.
>

Here is what 3.2 says:

       3.2  The solution MUST provide a mechanism to allow servers to
            simultaneously support clients using different revisions of
            modules.  A client's choice of particular revision of one or
            more modules may restrict the particular revision of other
            modules that may be used in the same request or session.

This does _not_ say servers MUST implement this.

Item 3.2 establishes a requirement and for some solutions it may be
easy to satisfy this requirement, for others it may be more costly to
satisfy this requirement.

The whole requirements exercise becomes a rather pointless exercise if
we remove requirements so that certain solutions look more attractive.
I have not seen a proposal that addresses all requirements and hence
at the end the WG needs to decide which tradeoffs make sense.

/js

-- 
Juergen Schoenwaelder           Jacobs University Bremen gGmbH
Phone: +49 421 200 3587         Campus Ring 1 | 28759 Bremen | Germany
Fax:   +49 421 200 3103         <https://www.jacobs-university.de/>