Re: [netmod] Management Protocol Roles: Client/Server vs Manager/Agent

Juergen Schoenwaelder <j.schoenwaelder@jacobs-university.de> Fri, 03 May 2019 16:14 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 3C3251200EF for <netmod@ietfa.amsl.com>; Fri, 3 May 2019 09:14:56 -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, 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 JOTIo3I0NaVW for <netmod@ietfa.amsl.com>; Fri, 3 May 2019 09:14:54 -0700 (PDT)
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 956511200E3 for <netmod@ietf.org>; Fri, 3 May 2019 09:14:53 -0700 (PDT)
Received: from localhost (demetrius5.irc-it.jacobs-university.de [10.70.0.222]) by atlas5.jacobs-university.de (Postfix) with ESMTP id 4CDBA7B8; Fri, 3 May 2019 18:14:52 +0200 (CEST)
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 0oRuuNGCESBs; Fri, 3 May 2019 18:14:52 +0200 (CEST)
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, 3 May 2019 18:14:52 +0200 (CEST)
Received: from localhost (demetrius5.irc-it.jacobs-university.de [10.70.0.222]) by hermes.jacobs-university.de (Postfix) with ESMTP id 0CF2F200E8; Fri, 3 May 2019 18:14:52 +0200 (CEST)
X-Virus-Scanned: amavisd-new at jacobs-university.de
Received: from hermes.jacobs-university.de ([212.201.44.23]) by localhost (demetrius5.jacobs-university.de [10.70.0.222]) (amavisd-new, port 10028) with ESMTP id 3QtHnHsbu467; Fri, 3 May 2019 18:14:51 +0200 (CEST)
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 B8CEA200E9; Fri, 3 May 2019 18:14:51 +0200 (CEST)
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 15.1.1713.5; Fri, 3 May 2019 18:14:51 +0200
Received: by anna.localdomain (Postfix, from userid 501) id DEF623008BDF29; Fri, 3 May 2019 18:14:50 +0200 (CEST)
Date: Fri, 03 May 2019 18:14:50 +0200
From: Juergen Schoenwaelder <j.schoenwaelder@jacobs-university.de>
To: "Schwarz Albrecht (ETAS/ESY1)" <Albrecht.Schwarz@etas.com>
CC: Andy Bierman <andy@yumaworks.com>, NetMod WG <netmod@ietf.org>
Message-ID: <20190503161450.p44lkz6cxzuwjc3d@anna.jacobs.jacobs-university.de>
Reply-To: Juergen Schoenwaelder <j.schoenwaelder@jacobs-university.de>
Mail-Followup-To: "Schwarz Albrecht (ETAS/ESY1)" <Albrecht.Schwarz@etas.com>, Andy Bierman <andy@yumaworks.com>, NetMod WG <netmod@ietf.org>
References: <941c9e23c3274dcdbca21c22348ca04f@etas.com>
MIME-Version: 1.0
Content-Type: text/plain; charset="us-ascii"
Content-Disposition: inline
In-Reply-To: <941c9e23c3274dcdbca21c22348ca04f@etas.com>
User-Agent: NeoMutt/20180716
X-ClientProxiedBy: SXCHMB04.jacobs.jacobs-university.de (10.70.0.156) To sxchmb03.jacobs.jacobs-university.de (10.70.0.155)
Archived-At: <https://mailarchive.ietf.org/arch/msg/netmod/QckJbmDtkTCqOwl2FSsBKQPdt8g>
Subject: Re: [netmod] Management Protocol Roles: Client/Server vs Manager/Agent
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, 03 May 2019 16:14:56 -0000

On Fri, May 03, 2019 at 10:43:50AM +0000, Schwarz Albrecht (ETAS/ESY1) wrote:

> Leading (for me) to a principle dilemma from (management) protocol engineering perspective due to
> a) Manager-to-Agent = 1:N
> b) Client-to-Server = N:1
> c) and the mapping approach in NETCONF/NETMOD of Manager-to-Client and Agent-to-Server in my understanding.

The problem is that you leave the plural 's' out. ;-)

Client-to-Server  is 1:1 (= Manager-to-Agent)
Client-to-Servers is 1:N (= Manager-to-Agents)
Clients-to-Server is N:1 (= Managers-to-Agent)

> I'm being aware that a distributed management solution needs to resolve the various role assignments in a layered management communication architecture at the various levels, e.g.,
> for Management Application MA-over-RESTCONF-over-HTTP-over-TCP-over- ... as
> 1) Application level (MA): Manager to Agent(s)
> 2) Application layer management protocol = RESTCONF: Manager to Agent(s)
> 3) Session layer = HTTP: Client(s) to Server
> 4) Transport layer = TCP: Client(s) to Server
> 
> I fail to see, or do miss the background/justification why the notion of client/server is used in RFCs about YANG, NMDA, NETCONF? Instead of manager/agent.
>

It all boils down how you define the terms Manager and Agent. With
NETCONF/RESTCONF and YANG, the initial focus was on the interaction
between the server maintaining configuration datastores and the client
manipulating configuration datastores (leaving out notifications for
now, they actually came later).

/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/>