[L2sm] R: R: Yangdoctors early review of draft-ietf-l2sm-l2vpn-service-model-08

Fioccola Giuseppe <giuseppe.fioccola@telecomitalia.it> Thu, 01 March 2018 09:56 UTC

Return-Path: <giuseppe.fioccola@telecomitalia.it>
X-Original-To: l2sm@ietfa.amsl.com
Delivered-To: l2sm@ietfa.amsl.com
Received: from localhost (localhost []) by ietfa.amsl.com (Postfix) with ESMTP id F1CE012D77D; Thu, 1 Mar 2018 01:56:13 -0800 (PST)
X-Virus-Scanned: amavisd-new at amsl.com
X-Spam-Flag: NO
X-Spam-Score: -2.61
X-Spam-Status: No, score=-2.61 tagged_above=-999 required=5 tests=[BAYES_00=-1.9, RCVD_IN_DNSWL_LOW=-0.7, SPF_PASS=-0.001, T_RP_MATCHES_RCVD=-0.01, URIBL_BLOCKED=0.001] autolearn=ham autolearn_force=no
Received: from mail.ietf.org ([]) by localhost (ietfa.amsl.com []) (amavisd-new, port 10024) with ESMTP id PX-mYb6ya96o; Thu, 1 Mar 2018 01:56:11 -0800 (PST)
Received: from mx01.telecomitalia.it (mx01.telecomitalia.it []) (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 908AC126CE8; Thu, 1 Mar 2018 01:56:10 -0800 (PST)
X-AuditID: d9a9790a-6abff70000008093-aa-5a97ce386014
Received: from TELMBXB02RM001.telecomitalia.local ( []) (using TLS with cipher ECDHE-RSA-AES256-SHA384 (256/256 bits)) (Client did not present a certificate) by mx01.telecomitalia.it () with SMTP id 25.94.32915.83EC79A5; Thu, 1 Mar 2018 10:56:08 +0100 (CET)
From: Fioccola Giuseppe <giuseppe.fioccola@telecomitalia.it>
To: Ladislav Lhotka <lhotka@nic.cz>, "yang-doctors@ietf.org" <yang-doctors@ietf.org>
CC: "l2sm@ietf.org" <l2sm@ietf.org>, "ietf@ietf.org" <ietf@ietf.org>, "draft-ietf-l2sm-l2vpn-service-model.all@ietf.org" <draft-ietf-l2sm-l2vpn-service-model.all@ietf.org>
Thread-Topic: R: Yangdoctors early review of draft-ietf-l2sm-l2vpn-service-model-08
Thread-Index: AQHTrv5AYyIDdm1EX0ihG0H5S7yR0qO5rvBQgAArYICAAUrXcA==
Date: Thu, 1 Mar 2018 09:56:07 +0000
Message-ID: <d70d9ad316f549a698a20f6fd0203c97@TELMBXB02RM001.telecomitalia.local>
References: <151964851123.31353.1471509914124380207@ietfa.amsl.com> <a29f08b341cd472597badb2e6e55463f@TELMBXB02RM001.telecomitalia.local> <1519829883.31583.17.camel@nic.cz>
In-Reply-To: <1519829883.31583.17.camel@nic.cz>
Accept-Language: it-IT, en-US
Content-Language: it-IT
x-ms-exchange-transport-fromentityheader: Hosted
x-originating-ip: []
x-ti-disclaimer: Disclaimer1
Content-Type: text/plain; charset="utf-8"
Content-Transfer-Encoding: base64
MIME-Version: 1.0
X-Brightmail-Tracker: H4sIAAAAAAAAA+NgFtrHKsWRmVeSWpSXmKPExsXCxfdHWtfi3PQog0+rZSy2TWthtHi2cT6L xZ2XLxktLqyay2bRt+sAowOrx5IlP5k8Nl2+wxjAFNXAaJOYl5dfkliSqpCSWpxsq+SSWZyc k5iZm1qkEJKak5qcn6ukkJliq2SspFCQk5icmpuaV2KrlFhQkJqXomTHpYABbIDKMvMUUvOS 81My89JtlTyD/XUtLEwtdQ2V7AJLU4tL8hVyU4uLE9PTM/MVUhPWC2bMmnGFuWCBckXLhXUs DYxrlLoYOTkkBEwkPmy/x9zFyMUhJDCFSWLXtLPMIAk2ARuJg69OsIHYIgJhEjv2f2UHKWIW WM8oMWPbckaQhLBAsETrs23sEEWhEqtmTwayOYBsJ4mjP6JATBYBFYm1j6JAKngFAiUmrnjO BrFrI6PEj+OXweZzCuhLvDrZDWYzCshKTNi9CGw8s4C4xIvpJ9ghDhWQWLLnPDOELSrx8vE/ VgjbQGLr0n0sELaixIld5xkhbBmJhUcms4LcwCygKbF+lz7ESEWJKd0P2SHuEZQ4OfMJywRG sVlIts1C6JiFpGMWko4FjCyrGEVzKwwM9UogsZdZkpiTmaiXWbKJEZhIbq6s5NrB+HqV8yFG AQ5GJR7eGfumRwmxJpYVV+YeYpTgYFYS4T29fVqUEG9KYmVValF+fFFpTmrxIUYfYHhNZJYS Tc4HJrm8knhDEwtLQ2MLCyNDCzNTHMJK4rzLKoFmCaQDk1d2ampBahHMOCYOTqkGxkSx+elX l5+wXeXa1ufd4+uRJcHZpLKW7+5Nvyvb9HMn8m9kYXLs4FryJ1fU91hZvNqPFdeq0uba8ZZx WR+V39B+rSBiqdXvoi/brnWIX7d2Yr4f3MqRO+3R/GcvT5Zk5PyWnqOUsPUXqwLnj9xffLcf JpgovfKb7nnDf+cx28/3/jleO+O0QYmlOCPRUIu5qDgRAMS7pmBRAwAA
Archived-At: <https://mailarchive.ietf.org/arch/msg/l2sm/HBlNZkQQtb1ULmJ171aOkRV5lpA>
Subject: [L2sm] R: R: Yangdoctors early review of draft-ietf-l2sm-l2vpn-service-model-08
X-BeenThere: l2sm@ietf.org
X-Mailman-Version: 2.1.22
Precedence: list
List-Id: "The Layer Two Virtual Private Network Service Model \(L2SM\)" <l2sm.ietf.org>
List-Unsubscribe: <https://www.ietf.org/mailman/options/l2sm>, <mailto:l2sm-request@ietf.org?subject=unsubscribe>
List-Archive: <https://mailarchive.ietf.org/arch/browse/l2sm/>
List-Post: <mailto:l2sm@ietf.org>
List-Help: <mailto:l2sm-request@ietf.org?subject=help>
List-Subscribe: <https://www.ietf.org/mailman/listinfo/l2sm>, <mailto:l2sm-request@ietf.org?subject=subscribe>
X-List-Received-Date: Thu, 01 Mar 2018 09:56:14 -0000

Hi Ladislav,
My answers inline tagged as [GF].

Best regards,


-----Messaggio originale-----
Da: Ladislav Lhotka [mailto:lhotka@nic.cz] 
Inviato: mercoledì 28 febbraio 2018 15:58
A: Fioccola Giuseppe; yang-doctors@ietf.org
Cc: l2sm@ietf.org; ietf@ietf.org; draft-ietf-l2sm-l2vpn-service-model.all@ietf.org
Oggetto: Re: R: Yangdoctors early review of draft-ietf-l2sm-l2vpn-service-model-08

Hi Giuseppe,

please see inline.

On Wed, 2018-02-28 at 13:15 +0000, Fioccola Giuseppe wrote:
> Hi Ladislav,
> Thank you! We are working on a new revision that incorporates your comments.
> My answers inline tagged as [GF].
> Best Regards,
> Giuseppe
> -----Messaggio originale-----
> Da: Ladislav Lhotka [mailto:lhotka@nic.cz]
> Inviato: lunedì 26 febbraio 2018 13:35
> A: yang-doctors@ietf.org
> Cc: l2sm@ietf.org; ietf@ietf.org; 
> draft-ietf-l2sm-l2vpn-service-model.all@ietf
> .org
> Oggetto: Yangdoctors early review of 
> draft-ietf-l2sm-l2vpn-service-model-08
> Reviewer: Ladislav Lhotka
> Review result: Ready with Issues
> **** General comments
>      - The 'ietf-l2vpn-svc' module contained in this document is
>        rather large: it defines 386 schema nodes, 35 features and 175
>        identities. It is therefore natural to ask whether the authors
>        considered splitting the definitions into multiple
>        modules. This would make the data model more modular and
>        probably also make some of the features unnecessary. See also
>        draft-ietf-netmod-rfc6087bis-18, sec. 4.17.
> [GF]: Ok, Thanks for the suggestion. We will remove unnecessary 
> identities, features. Note that unlike network element model, service 
> model will describe various aspects of network infrastructure, 
> including devices and their subsystems, and relevant protocols 
> operating at the link and network layers across multiple device. So it is intentional to have such model design.

Yes, but RFC 8199 also talks about monolithic versus component-based approaches in relation to network service models. I am not saying that your design is wrong, just suggesting to consider the alternatives that could possibly make this relatively big data model easier to comprehend.

[GF]: We would prefer to keep L2SM aligned with RFC 8299 (L3SM) by using a similar approach and we will try to simplify as much as we can as it is suggested by RFC 8199.

>      - The module defines most containers, lists and even individual
>        leaves in a grouping that is then used only once. This approach
>        has its pros nad cons but it is not the common practice in YANG
>        modelling - groupings are mostly defined only if they are used (or
>        expected to be used) repeatedly and/or in different modules.
> [GF]: It is expected some of these groupings can be reused in some 
> other external modules, or model extension.

If only some of them are intended to be reused, then I would suggest to remove those that aren't. Model extensions are usually implemented with an augment, and groupings don't help in this case.

[GF]: Understand. Will check and remove those that are not reused. 

Thanks, Lada

Ladislav Lhotka
Head, CZ.NIC Labs
PGP Key ID: 0xB8F92B08A9F76C67

Questo messaggio e i suoi allegati sono indirizzati esclusivamente alle persone indicate. La diffusione, copia o qualsiasi altra azione derivante dalla conoscenza di queste informazioni sono rigorosamente vietate. Qualora abbiate ricevuto questo documento per errore siete cortesemente pregati di darne immediata comunicazione al mittente e di provvedere alla sua distruzione, Grazie. 

This e-mail and any attachments is confidential and may contain privileged information intended for the addressee(s) only. Dissemination, copying, printing or use by anybody else is unauthorised. If you are not the intended recipient, please delete this message and any attachments and advise the sender by return e-mail, Thanks. 

Rispetta l'ambiente. Non stampare questa mail se non è necessario.