Re: [netmod] New Version Notification for draft-verdt-netmod-yang-versioning-reqs-01.txt
Martin Bjorklund <mbj@tail-f.com> Mon, 12 November 2018 16:21 UTC
Return-Path: <mbj@tail-f.com>
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 DCC3C130E1D for <netmod@ietfa.amsl.com>; Mon, 12 Nov 2018 08:21:59 -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, SPF_PASS=-0.001, URIBL_BLOCKED=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 O__MF7_fv_eq for <netmod@ietfa.amsl.com>; Mon, 12 Nov 2018 08:21:57 -0800 (PST)
Received: from mail.tail-f.com (mail.tail-f.com [46.21.102.45]) by ietfa.amsl.com (Postfix) with ESMTP id 9665912F1AC for <netmod@ietf.org>; Mon, 12 Nov 2018 08:21:57 -0800 (PST)
Received: from localhost (unknown [173.38.220.61]) by mail.tail-f.com (Postfix) with ESMTPSA id 0DE1E1AE0290; Mon, 12 Nov 2018 17:21:56 +0100 (CET)
Date: Mon, 12 Nov 2018 17:21:55 +0100
Message-Id: <20181112.172155.1599685820248587823.mbj@tail-f.com>
To: j.schoenwaelder@jacobs-university.de
Cc: andy@yumaworks.com, netmod@ietf.org
From: Martin Bjorklund <mbj@tail-f.com>
In-Reply-To: <20181109165512.6f3hi55mv2kc3qlp@anna.jacobs.jacobs-university.de>
References: <20181109151347.3xms2cty6hxyl232@anna.jacobs.jacobs-university.de> <20181109.173159.1522007243611164311.mbj@tail-f.com> <20181109165512.6f3hi55mv2kc3qlp@anna.jacobs.jacobs-university.de>
X-Mailer: Mew version 6.7 on Emacs 24.5 / Mule 6.0 (HANACHIRUSATO)
Mime-Version: 1.0
Content-Type: Text/Plain; charset="us-ascii"
Content-Transfer-Encoding: 7bit
Archived-At: <https://mailarchive.ietf.org/arch/msg/netmod/y9bG0F2VKVG7rmZY9Z87zogmU4U>
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: Mon, 12 Nov 2018 16:22:00 -0000
Juergen Schoenwaelder <j.schoenwaelder@jacobs-university.de> wrote: > On Fri, Nov 09, 2018 at 05:31:59PM +0100, Martin Bjorklund wrote: > > Juergen Schoenwaelder <j.schoenwaelder@jacobs-university.de> wrote: > > > 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. > > > > Ok, but that's not what I wrote. I don't agree with this requirement > > which says that it MUST be possible for a server to support > > different revisions of a given module (again, if this is not the > > intention of the text, please clarify). I simply don't think that > > this is a good requirement. > > > > I can't follow you or I do not understand what you are after. > > In some versioning schemes, providing support for different > 'versions' is relatively easy. If I have modules foo-1 and foo-2, > then I can implement foo-1 and foo-2 (or proper workable subsets of > them) easily. And older clients expecting foo-1 may continue to work > while newer clients move to foo-2. In other versioning schemes, > providing the same possibility to migrate from foo version 1 to foo > version 2, would lead to the support of foo in two different > versions. But module 'foo-2' is not a new revision of module 'foo-1'. It might be that 'foo-2' represents a new version of the underlying "function" that 'foo-1' represents; but that is a different issue. > The requirement tries to express that it must be possible to have a > transition path where old clients can continue to function with the > old version while new clients start using the new version. The idea is > to state this as a requirement without making any assumptions about > the solutions. > > Are you saying that a requirement saying that there should be a > possibility of a transition path is in general a bad requirement? No (but I agree w/ Rob Wilton that it is unclear how this should be done in non-trivial examples), but again, that is not what I think 3.2 says. IMO 3.2 doesn't allow a solution that requires a new module for new NBC stuff, since it says that a client should be able to pick a particular revision of a module. /martin > > /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/> >
- [netmod] Fwd: New Version Notification for draft-… Joe Clarke
- Re: [netmod] New Version Notification for draft-v… Christian Hopps
- Re: [netmod] New Version Notification for draft-v… Robert Wilton
- Re: [netmod] New Version Notification for draft-v… Andy Bierman
- Re: [netmod] New Version Notification for draft-v… Christian Hopps
- Re: [netmod] New Version Notification for draft-v… Robert Wilton
- Re: [netmod] New Version Notification for draft-v… Juergen Schoenwaelder
- Re: [netmod] New Version Notification for draft-v… Andy Bierman
- Re: [netmod] New Version Notification for draft-v… Robert Wilton
- Re: [netmod] New Version Notification for draft-v… Juergen Schoenwaelder
- Re: [netmod] New Version Notification for draft-v… Andy Bierman
- Re: [netmod] New Version Notification for draft-v… Juergen Schoenwaelder
- Re: [netmod] New Version Notification for draft-v… Andy Bierman
- Re: [netmod] New Version Notification for draft-v… Juergen Schoenwaelder
- Re: [netmod] New Version Notification for draft-v… Balázs Lengyel
- Re: [netmod] New Version Notification for draft-v… Balázs Lengyel
- Re: [netmod] New Version Notification for draft-v… Andy Bierman
- Re: [netmod] New Version Notification for draft-v… Martin Bjorklund
- Re: [netmod] New Version Notification for draft-v… Martin Bjorklund
- Re: [netmod] Fwd: New Version Notification for dr… Martin Bjorklund
- Re: [netmod] Fwd: New Version Notification for dr… Joe Clarke
- Re: [netmod] New Version Notification for draft-v… Juergen Schoenwaelder
- Re: [netmod] New Version Notification for draft-v… Andy Bierman
- Re: [netmod] New Version Notification for draft-v… Martin Bjorklund
- Re: [netmod] Fwd: New Version Notification for dr… Martin Bjorklund
- Re: [netmod] New Version Notification for draft-v… Reshad Rahman (rrahman)
- Re: [netmod] New Version Notification for draft-v… Martin Bjorklund
- Re: [netmod] New Version Notification for draft-v… Reshad Rahman (rrahman)
- Re: [netmod] New Version Notification for draft-v… Reshad Rahman (rrahman)
- Re: [netmod] New Version Notification for draft-v… Martin Bjorklund
- Re: [netmod] New Version Notification for draft-v… Juergen Schoenwaelder
- Re: [netmod] New Version Notification for draft-v… Martin Bjorklund
- Re: [netmod] New Version Notification for draft-v… Juergen Schoenwaelder
- Re: [netmod] New Version Notification for draft-v… Robert Wilton
- Re: [netmod] New Version Notification for draft-v… Robert Wilton
- Re: [netmod] Fwd: New Version Notification for dr… Ebben Aries
- Re: [netmod] New Version Notification for draft-v… Andy Bierman
- Re: [netmod] New Version Notification for draft-v… Robert Wilton
- Re: [netmod] New Version Notification for draft-v… Martin Bjorklund
- Re: [netmod] New Version Notification for draft-v… Juergen Schoenwaelder
- Re: [netmod] New Version Notification for draft-v… Martin Bjorklund
- Re: [netmod] New Version Notification for draft-v… Robert Wilton