Re: [core] Core Link Format

Carsten Bormann <cabo@tzi.org> Mon, 11 November 2019 16:07 UTC

Return-Path: <cabo@tzi.org>
X-Original-To: core@ietfa.amsl.com
Delivered-To: core@ietfa.amsl.com
Received: from localhost (localhost [127.0.0.1]) by ietfa.amsl.com (Postfix) with ESMTP id B841C1208B0 for <core@ietfa.amsl.com>; Mon, 11 Nov 2019 08:07:40 -0800 (PST)
X-Virus-Scanned: amavisd-new at amsl.com
X-Spam-Flag: NO
X-Spam-Score: -3.6
X-Spam-Level:
X-Spam-Status: No, score=-3.6 tagged_above=-999 required=5 tests=[BAYES_00=-1.9, RCVD_IN_DNSWL_MED=-2.3, SPF_HELO_NONE=0.001, SPF_PASS=-0.001, URIBL_SBL=0.5, URIBL_SBL_A=0.1] 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 YlQeLOo5ZIND for <core@ietfa.amsl.com>; Mon, 11 Nov 2019 08:07:37 -0800 (PST)
Received: from gabriel-vm-2.zfn.uni-bremen.de (gabriel-vm-2.zfn.uni-bremen.de [134.102.50.17]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by ietfa.amsl.com (Postfix) with ESMTPS id 1EBAB1208A4 for <core@ietf.org>; Mon, 11 Nov 2019 08:07:35 -0800 (PST)
Received: from [192.168.217.102] (p548DC893.dip0.t-ipconnect.de [84.141.200.147]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by gabriel-vm-2.zfn.uni-bremen.de (Postfix) with ESMTPSA id 47BbPK2LJ5zySN; Mon, 11 Nov 2019 17:07:33 +0100 (CET)
Content-Type: text/plain; charset="utf-8"
Mime-Version: 1.0 (Mac OS X Mail 11.5 \(3445.9.1\))
From: Carsten Bormann <cabo@tzi.org>
In-Reply-To: <CAAzbHvbEDMTxtbnUK7xvLytpFJszYmHoDvEojzcrkJyD4KE1mA@mail.gmail.com>
Date: Mon, 11 Nov 2019 17:07:43 +0100
Cc: Hannes Tschofenig <Hannes.Tschofenig@arm.com>, "core@ietf.org WG" <core@ietf.org>
X-Mao-Original-Outgoing-Id: 595181261.88094-686133f2866bf47cb3e7595635407de3
Content-Transfer-Encoding: quoted-printable
Message-Id: <13D4B0E0-0653-4C3B-82B0-D8AA2AC9E37D@tzi.org>
References: <VI1PR08MB53608C867775D1F1F7051368FA780@VI1PR08MB5360.eurprd08.prod.outlook.com> <CAAzbHvbEDMTxtbnUK7xvLytpFJszYmHoDvEojzcrkJyD4KE1mA@mail.gmail.com>
To: Klaus Hartke <hartke@projectcool.de>
X-Mailer: Apple Mail (2.3445.9.1)
Archived-At: <https://mailarchive.ietf.org/arch/msg/core/x2l3oMuCK_1MC-6tXQslbRpu4dU>
Subject: Re: [core] Core Link Format
X-BeenThere: core@ietf.org
X-Mailman-Version: 2.1.29
Precedence: list
List-Id: "Constrained RESTful Environments \(CoRE\) Working Group list" <core.ietf.org>
List-Unsubscribe: <https://www.ietf.org/mailman/options/core>, <mailto:core-request@ietf.org?subject=unsubscribe>
List-Archive: <https://mailarchive.ietf.org/arch/browse/core/>
List-Post: <mailto:core@ietf.org>
List-Help: <mailto:core-request@ietf.org?subject=help>
List-Subscribe: <https://www.ietf.org/mailman/listinfo/core>, <mailto:core-request@ietf.org?subject=subscribe>
X-List-Received-Date: Mon, 11 Nov 2019 16:07:41 -0000

On Nov 11, 2019, at 16:35, Klaus Hartke <hartke@projectcool.de> wrote:
> 
> I don't have a comprehensive write-up, but a few items from the top of
> my head below.

Hi Klaus,

thanks for providing the details.

My view of the high-level summary is that link-format is still fine to do the things that it originally was designed to do: Provide a self-description of a device by listing its resources, enable the aggregation of these self-descriptions in a resource directory.

When the potential became apparent to use link-format as a more general application format, the idiosyncrasies started to be a problem.  We noticed this when we tried to standardize links-json, which originally was intended to be bug-for-bug compatible with link-format but started morphing away from that.  Because we didn’t want to “break” link-format by creating “an almost but not entirely unlike” derivative, we stopped working on links-json and started to pay attention to CoRAL for the next step towards a general application format.

So the assumption is that CoRAL will serve as the improved basis for future applications that will include those now handled by link-format, but since this is a new format, there is no need to break the existing applications of link-format.

Grüße, Carsten