[bess] PLEASE LOOK: minor change to draft-ietf-bess-evpn-df-election-framework-05 => two weeks poll to get feedback

<stephane.litkowski@orange.com> Wed, 21 November 2018 09:08 UTC

Return-Path: <stephane.litkowski@orange.com>
X-Original-To: bess@ietfa.amsl.com
Delivered-To: bess@ietfa.amsl.com
Received: from localhost (localhost [127.0.0.1]) by ietfa.amsl.com (Postfix) with ESMTP id B65D8130EE7; Wed, 21 Nov 2018 01:08:48 -0800 (PST)
X-Virus-Scanned: amavisd-new at amsl.com
X-Spam-Flag: NO
X-Spam-Score: -2.599
X-Spam-Level:
X-Spam-Status: No, score=-2.599 tagged_above=-999 required=5 tests=[BAYES_00=-1.9, HTML_MESSAGE=0.001, RCVD_IN_DNSWL_LOW=-0.7, SPF_PASS=-0.001, UNPARSEABLE_RELAY=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 JREKrYTnwvvT; Wed, 21 Nov 2018 01:08:46 -0800 (PST)
Received: from orange.com (mta239.mail.business.static.orange.com [80.12.66.39]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by ietfa.amsl.com (Postfix) with ESMTPS id 33A1B128D68; Wed, 21 Nov 2018 01:08:46 -0800 (PST)
Received: from opfedar07.francetelecom.fr (unknown [xx.xx.xx.9]) by opfedar24.francetelecom.fr (ESMTP service) with ESMTP id 430Gvw10W6z5vcv; Wed, 21 Nov 2018 10:08:44 +0100 (CET)
Received: from Exchangemail-eme2.itn.ftgroup (unknown [xx.xx.31.18]) by opfedar07.francetelecom.fr (ESMTP service) with ESMTP id 430Gvw00G6z5vN0; Wed, 21 Nov 2018 10:08:44 +0100 (CET)
Received: from OPEXCLILMA4.corporate.adroot.infra.ftgroup ([fe80::65de:2f08:41e6:ebbe]) by OPEXCLILM34.corporate.adroot.infra.ftgroup ([fe80::cba:56d0:a732:ef5a%19]) with mapi id 14.03.0415.000; Wed, 21 Nov 2018 10:08:43 +0100
From: <stephane.litkowski@orange.com>
To: "Ali Sajassi (sajassi)" <sajassi@cisco.com>, "bess@ietf.org" <bess@ietf.org>
CC: "bess-chairs@ietf.org" <bess-chairs@ietf.org>, "martin.vigoureux@nokia.com" <martin.vigoureux@nokia.com>
Thread-Topic: PLEASE LOOK: minor change to draft-ietf-bess-evpn-df-election-framework-05 => two weeks poll to get feedback
Thread-Index: AdSBeVzJDePAdkxYRPe/rc2WvXNgcw==
Date: Wed, 21 Nov 2018 09:08:43 +0000
Message-ID: <14620_1542791324_5BF5209C_14620_311_1_9E32478DFA9976438E7A22F69B08FF924B772FA0@OPEXCLILMA4.corporate.adroot.infra.ftgroup>
Accept-Language: fr-FR, en-US
Content-Language: en-US
X-MS-Has-Attach:
X-MS-TNEF-Correlator:
x-originating-ip: [10.168.234.4]
Content-Type: multipart/alternative; boundary="_000_9E32478DFA9976438E7A22F69B08FF924B772FA0OPEXCLILMA4corp_"
MIME-Version: 1.0
Archived-At: <https://mailarchive.ietf.org/arch/msg/bess/BbweMfZ669JB25hUO_Xx_n_iNl0>
Subject: [bess] PLEASE LOOK: minor change to draft-ietf-bess-evpn-df-election-framework-05 => two weeks poll to get feedback
X-BeenThere: bess@ietf.org
X-Mailman-Version: 2.1.29
Precedence: list
List-Id: BGP-Enabled ServiceS working group discussion list <bess.ietf.org>
List-Unsubscribe: <https://www.ietf.org/mailman/options/bess>, <mailto:bess-request@ietf.org?subject=unsubscribe>
List-Archive: <https://mailarchive.ietf.org/arch/browse/bess/>
List-Post: <mailto:bess@ietf.org>
List-Help: <mailto:bess-request@ietf.org?subject=help>
List-Subscribe: <https://www.ietf.org/mailman/listinfo/bess>, <mailto:bess-request@ietf.org?subject=subscribe>
X-List-Received-Date: Wed, 21 Nov 2018 09:08:49 -0000

Hi Ali,

Thanks a lot for your email.

Speaking as chair, could you please highlight to the working group the rationale of the change and associated use case ? Just to give the context…


To WG Folks,

Please review this change with care. There are two points that I would like to highlight:


-          We need to ensure that there is no current implementation using the value 255. Please raise your voice if you are aware of one.

-          The encoding of the mcast DF election algorithm could now be decorrelated from the base DF alg (applicable to Broadcast and Unknown traffic). The proposed encoding uses 3 bits for the mcast DF alg. We have to ensure that:

o   3 bits is enough

o   There will “never” (at least not mid term) be a requirement for variable parameters for mcast DF election (like in DF pref draft).

I will let some time to think about this change and raise your support or concerns.
The poll starts now and will end on Dec 5th.
This DF election framework will be an important component of EVPN and we need to ensure that we are providing the required level of flexibility to address the different use cases.

Thanks !


From: Ali Sajassi (sajassi) [mailto:sajassi@cisco.com]
Sent: Wednesday, November 21, 2018 00:25
To: bess@ietf.org
Cc: bess-chairs@ietf.org
Subject: minor change to draft-ietf-bess-evpn-df-election-framework-05


Folks,

The authors of  the above draft are purposing a minor change to the draft and since the draft is currently under review by IESG, the chair has asked to send an email to the WG to solicit inputs and ensuring that there is no objection. The proposed change is as follow:

Currently, the above draft defines an eight-bit “DF Alg” field as shown in the following figure. The proposed change is to reduce the eight-bit field to a five-bit field.

*** OLD Text

              0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
             +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
             | Type=0x06     | Sub-Type(0x06)|   DF Alg      |    Bitmap     |
             +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
             |     Bitmap    |            Reserved                           |
             +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+


   o DF Alg (1 octet) - Encodes the DF Election algorithm values
     (between 0 and 255) that the advertising PE desires to use for the
     ES. This document requests IANA to set up a registry called "DF Alg
     Registry" and solicits the following values:

     - Type 0: Default DF Election algorithm, or modulus-based algorithm
       as in [RFC7432<https://tools.ietf.org/html/rfc7432>]2>].

     - Type 1: HRW algorithm (explained in this document).

     - Types 2-254: Unassigned.

     - Type 255: Reserved for Experimental Use.

***NEW Text

              0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
             +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
             | Type=0x06     | Sub-Type(0x06)| RSV |  DF Alg  |    Bitmap    |
             +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
             |     Bitmap    |            Reserved                           |
             +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+


   o DF Alg (5 bits) - Encodes the DF Election algorithm values
     (between 0 and 31) that the advertising PE desires to use for the
     ES. This document requests IANA to set up a registry called "DF Alg
     Registry" and solicits the following values:

     - Type 0: Default DF Election algorithm, or modulus-based algorithm
       as in [RFC7432<https://tools.ietf.org/html/rfc7432>]2>].

     - Type 1: HRW algorithm (explained in this document).

     - Types 2-30: Unassigned.

     - Type 31: Reserved for Experimental Use.


The remaining 3-bits of that octet (bits 16, 17, and 18 in the above figure) will be used by per-mcast-flow-df-election and will be expanded and described there and will be discussed in the next IETF as usual at the BESS WG session.

Regards,
Ali & other co-authors

_________________________________________________________________________________________________________________________

Ce message et ses pieces jointes peuvent contenir des informations confidentielles ou privilegiees et ne doivent donc
pas etre diffuses, exploites ou copies sans autorisation. Si vous avez recu ce message par erreur, veuillez le signaler
a l'expediteur et le detruire ainsi que les pieces jointes. Les messages electroniques etant susceptibles d'alteration,
Orange decline toute responsabilite si ce message a ete altere, deforme ou falsifie. Merci.

This message and its attachments may contain confidential or privileged information that may be protected by law;
they should not be distributed, used or copied without authorisation.
If you have received this email in error, please notify the sender and delete this message and its attachments.
As emails may be altered, Orange is not liable for messages that have been modified, changed or falsified.
Thank you.