Re: [Lsr] Flooding Topology Computation Algorithm - draft-cc-lsr-flooding-reduction-08 Working Group Adoption Call

Huaimo Chen <huaimo.chen@futurewei.com> Sat, 06 June 2020 01:34 UTC

Return-Path: <huaimo.chen@futurewei.com>
X-Original-To: lsr@ietfa.amsl.com
Delivered-To: lsr@ietfa.amsl.com
Received: from localhost (localhost [127.0.0.1]) by ietfa.amsl.com (Postfix) with ESMTP id 454A73A07DF for <lsr@ietfa.amsl.com>; Fri, 5 Jun 2020 18:34:09 -0700 (PDT)
X-Virus-Scanned: amavisd-new at amsl.com
X-Spam-Flag: NO
X-Spam-Score: -1.989
X-Spam-Level:
X-Spam-Status: No, score=-1.989 tagged_above=-999 required=5 tests=[BAYES_00=-1.9, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, HTML_MESSAGE=0.001, HTTPS_HTTP_MISMATCH=0.1, RCVD_IN_MSPIKE_H2=-0.001, T_SPF_PERMERROR=0.01, URIBL_BLOCKED=0.001] autolearn=unavailable autolearn_force=no
Authentication-Results: ietfa.amsl.com (amavisd-new); dkim=pass (1024-bit key) header.d=futurewei.com
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 dJZ99vHkIXn4 for <lsr@ietfa.amsl.com>; Fri, 5 Jun 2020 18:34:06 -0700 (PDT)
Received: from NAM11-DM6-obe.outbound.protection.outlook.com (mail-dm6nam11on2098.outbound.protection.outlook.com [40.107.223.98]) (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 214E13A07DC for <lsr@ietf.org>; Fri, 5 Jun 2020 18:34:05 -0700 (PDT)
ARC-Seal: i=1; a=rsa-sha256; s=arcselector9901; d=microsoft.com; cv=none; b=EhVsIkk2axzbLO7rqOPA7EFNcbvoVAVDQE+f9k7vuLjOmzLNSRq/qEQ/iALW+RLCT/KSlYxbw6pWB0Hs2P3FIOaPJKeHQl9mSfyXionPl8iDUjPQXMq4W7vPbt2gID7ZrGuUdAS6dmQQnMvPq2F0UZ/SScWVCQDG1pjrLz12BGclKbJ9ouSG6vOO5LpZG9q0SSexb4cGNuQwohht75IP5wR/LnLv/sPKJc/NgZ1c7UJEVC1W6ou/tYrlCdwrPj48efjGdKBM9iyu11Tq/d7lxGXF3LBYtJldx7g+il7FY7pLeOe/qi46XEgmfILg9DhmZYvIRW/6PEJHB3pKwtSVeg==
ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=microsoft.com; s=arcselector9901; h=From:Date:Subject:Message-ID:Content-Type:MIME-Version:X-MS-Exchange-SenderADCheck; bh=62in63Vv3Ma6QGobOV+P/na1oIaMr8/4WtOwH0YUHjU=; b=VrNlisrVEJGajH1YRQNHDfPL8r7ZpCoCkSr6/N1kWRIJEzqROvJiCqxZmP/uokLNGK8YiJorWi0Si2V/87bDUp91MopzljEMqiKtoTTx3jH7P7H1igl4tk2bMaAWNqJyt0WLErgrSppthJe+ItfD/NtS0XkFsvn9NSAiAknXgidpW3UfCa5DGN9e0/imR6Xrky4b0nVnAADPH0AscsmBPpkXirGWQVumVyL6qaYG743ToWKwBKJDrN8lNeQhnLuXJEIeboplcWQeMvvYScwpqs9+10+MJvjFhDD4ieB+ld3Ap8IJ8hQiubAYu0DwOrtbZOqMmcPb46qx93Wvf4+QCg==
ARC-Authentication-Results: i=1; mx.microsoft.com 1; spf=pass smtp.mailfrom=futurewei.com; dmarc=pass action=none header.from=futurewei.com; dkim=pass header.d=futurewei.com; arc=none
DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=Futurewei.com; s=selector2; h=From:Date:Subject:Message-ID:Content-Type:MIME-Version:X-MS-Exchange-SenderADCheck; bh=62in63Vv3Ma6QGobOV+P/na1oIaMr8/4WtOwH0YUHjU=; b=h/TY1tb2ivvRpDOKrJKeqLaYi5JV+5Xs+rIAwtKRupBITUWgMcXQsaKKCXbMtRpiebqf9GWEDLsgXwa5iRqL9sY1KGSL2UMSLw79rGy8+7Q8lyeaWwuObsD9fsPKPo5tUdqmgCOxGNhGpUKjtR7Pox4SxLAyqysmfDa0E43KtNQ=
Received: from MN2PR13MB3117.namprd13.prod.outlook.com (2603:10b6:208:13a::20) by MN2PR13MB3903.namprd13.prod.outlook.com (2603:10b6:208:1e9::18) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.20.3088.10; Sat, 6 Jun 2020 01:34:03 +0000
Received: from MN2PR13MB3117.namprd13.prod.outlook.com ([fe80::d5b6:8550:9c40:eec2]) by MN2PR13MB3117.namprd13.prod.outlook.com ([fe80::d5b6:8550:9c40:eec2%7]) with mapi id 15.20.3088.011; Sat, 6 Jun 2020 01:34:03 +0000
From: Huaimo Chen <huaimo.chen@futurewei.com>
To: Yingzhen Qu <yingzhen.qu@futurewei.com>, "Acee Lindem (acee)" <acee=40cisco.com@dmarc.ietf.org>, "lsr@ietf.org" <lsr@ietf.org>
Thread-Topic: [Lsr] Flooding Topology Computation Algorithm - draft-cc-lsr-flooding-reduction-08 Working Group Adoption Call
Thread-Index: AQHWO1m9yw++VQZRYkaPzDWvpZxjvKjJ9X6AgADRPQg=
Date: Sat, 6 Jun 2020 01:34:02 +0000
Message-ID: <MN2PR13MB3117EB41C62ACA633A327B04F2870@MN2PR13MB3117.namprd13.prod.outlook.com>
References: <7B1E9ED7-F2B6-45AA-9E64-AD9E5B439D02@cisco.com>, <8FACDF6D-B0E7-4EE5-B568-A32450D8BA5F@futurewei.com>
In-Reply-To: <8FACDF6D-B0E7-4EE5-B568-A32450D8BA5F@futurewei.com>
Accept-Language: en-US
Content-Language: en-US
X-MS-Has-Attach:
X-MS-TNEF-Correlator:
authentication-results: futurewei.com; dkim=none (message not signed) header.d=none;futurewei.com; dmarc=none action=none header.from=futurewei.com;
x-originating-ip: [2601:199:4300:8e5a:c095:f5b8:b820:8e41]
x-ms-publictraffictype: Email
x-ms-office365-filtering-correlation-id: 00ed61ca-dd6b-48fd-c650-08d809b9b1f6
x-ms-traffictypediagnostic: MN2PR13MB3903:
x-ms-exchange-transport-forked: True
x-microsoft-antispam-prvs: <MN2PR13MB39030AE9ACAE51BB2F1D5D75F2870@MN2PR13MB3903.namprd13.prod.outlook.com>
x-ms-oob-tlc-oobclassifiers: OLM:10000;
x-forefront-prvs: 04267075BD
x-ms-exchange-senderadcheck: 1
x-microsoft-antispam: BCL:0;
x-microsoft-antispam-message-info: Upx+y7eSGi9McwMR5Bs+pYyA2vliaccVvtq+fXRSdkpRqFFoswDLz4uO0Z6XAJkvPUBSlGGDSCPO6M8ZzlhuoZb6PQ1gqizjcaGWxTwZu12L5ly3a+rnYZWdyrwLizmcipQ8eGDjMelrKtG8ukjVtzklEDdv/ssxo6gl7VZ/U7JoI9juQsYXG1/mK3zYyuCbj0kjGh+lkm+6JbE1Myji/ZMtT2ok/rOTMJmMCXHj1w2kZeYN1FeTli1RnWofh38hX4X2HKIUprypo4K7crXisT3M5LU7RQeFk8ug4SEsoh1qLdR+qf+3vHBXS/Qc5S1+Ws36ZY+fLQrhM2JOj4hAgXU3cb+mcY2VCzAAw7olrNaM1l8KZZCK1WqG+kHw1O6qvJ0ArzbeneXd+zBOcFXyYw==
x-forefront-antispam-report: CIP:255.255.255.255; CTRY:; LANG:en; SCL:1; SRV:; IPV:NLI; SFV:NSPM; H:MN2PR13MB3117.namprd13.prod.outlook.com; PTR:; CAT:NONE; SFTY:; SFS:(4636009)(376002)(396003)(39850400004)(346002)(136003)(366004)(6506007)(19627405001)(55016002)(2906002)(66476007)(83380400001)(71200400001)(66556008)(9686003)(8676002)(53546011)(64756008)(478600001)(66946007)(66446008)(66574014)(166002)(33656002)(7696005)(110136005)(52536014)(316002)(86362001)(76116006)(5660300002)(966005)(8936002)(44832011)(186003); DIR:OUT; SFP:1102;
x-ms-exchange-antispam-messagedata: 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
Content-Type: multipart/alternative; boundary="_000_MN2PR13MB3117EB41C62ACA633A327B04F2870MN2PR13MB3117namp_"
MIME-Version: 1.0
X-OriginatorOrg: Futurewei.com
X-MS-Exchange-CrossTenant-Network-Message-Id: 00ed61ca-dd6b-48fd-c650-08d809b9b1f6
X-MS-Exchange-CrossTenant-originalarrivaltime: 06 Jun 2020 01:34:03.0365 (UTC)
X-MS-Exchange-CrossTenant-fromentityheader: Hosted
X-MS-Exchange-CrossTenant-id: 0fee8ff2-a3b2-4018-9c75-3a1d5591fedc
X-MS-Exchange-CrossTenant-mailboxtype: HOSTED
X-MS-Exchange-CrossTenant-userprincipalname: 6qx/Cn9QIuDszQO2wZfZ1iekwvNP9drem23SgYl3sKe16p+mlo6aJ+qQPHZbo840UeKI78j262cgAZDsVHdh1g==
X-MS-Exchange-Transport-CrossTenantHeadersStamped: MN2PR13MB3903
Archived-At: <https://mailarchive.ietf.org/arch/msg/lsr/PUv0fk2VAVTferDUq1zxkb9AbOs>
Subject: Re: [Lsr] Flooding Topology Computation Algorithm - draft-cc-lsr-flooding-reduction-08 Working Group Adoption Call
X-BeenThere: lsr@ietf.org
X-Mailman-Version: 2.1.29
Precedence: list
List-Id: Link State Routing Working Group <lsr.ietf.org>
List-Unsubscribe: <https://www.ietf.org/mailman/options/lsr>, <mailto:lsr-request@ietf.org?subject=unsubscribe>
List-Archive: <https://mailarchive.ietf.org/arch/browse/lsr/>
List-Post: <mailto:lsr@ietf.org>
List-Help: <mailto:lsr-request@ietf.org?subject=help>
List-Subscribe: <https://www.ietf.org/mailman/listinfo/lsr>, <mailto:lsr-request@ietf.org?subject=subscribe>
X-List-Received-Date: Sat, 06 Jun 2020 01:34:09 -0000

Hi Yingzhen,

    Thank you very much for your support and comment.
    My answer/explanation is inline below.

Best Regards,
Huaimo
________________________________
From: Yingzhen Qu <yingzhen.qu@futurewei.com>
Sent: Friday, June 5, 2020 3:37 PM
To: Acee Lindem (acee) <acee=40cisco.com@dmarc.ietf.org>rg>; lsr@ietf.org <lsr@ietf.org>rg>; Huaimo Chen <huaimo.chen@futurewei.com>
Subject: Re: [Lsr] Flooding Topology Computation Algorithm - draft-cc-lsr-flooding-reduction-08 Working Group Adoption Call


Hi,



I support adoption of this draft.



Hi Huaimo,



I have a question regarding the draft. At the end of section 3, it says if there is any change in the base topology, the flooding topology MUST be re-computed. So in case of a link failure in the base topo, it’s possible that the link is not part of the flooding topology (e.g. one of the multiple links between two nodes), it might be optimal if we can figure it out and save recalculation here.

[HC]: This will make sure that the flooding topologies computed by all the routers will be the same. If the algorithm does not compute a new flooding topology when a link that is not on the current flooding topology fails, we need prove that in any sequence of changes in base topology reaching to different LSDBs in different times the flooding topology computed by the algorithm on one router will be the same as the one computed by the algorithm on another router in this way.  After there is a proof, the optimized algorithm can be used.



Thanks,

Yingzhen



From: Lsr <lsr-bounces@ietf.org> on behalf of "Acee Lindem (acee)" <acee=40cisco.com@dmarc.ietf.org>
Date: Friday, June 5, 2020 at 10:09 AM
To: "lsr@ietf.org" <lsr@ietf.org>
Subject: Re: [Lsr] Flooding Topology Computation Algorithm - draft-cc-lsr-flooding-reduction-08 Working Group Adoption Call
Resent-From: <yingzhen.qu@huawei.com>



Speaking as WG Member:



Hi Authors,



I have a couple technical comments on the draft.



  1.  The algorithm only computes a single graph with single path to each node. While I-D.ietf-lsr-dynamic-flooding failure and computation of an updated flooding topology, many of the other algorithms (both draft and proprietary) attempt to compute two or more paths to each node.
  2.  Since this algorithm is slated for use as a distributed algorithm, all routers in the area must use the same value for MaxD or they may compute different flooding topologies. This is cannot be guaranteed by a single algorithm IANA value unless we allow some number of algorithm specific parameters to be advertised by the area leader (which might not be a bad idea).
  3.   Similarly, the constraints in section 4.2 must be applied uniformly and different constraints would require new IANA algorithm allocation.



Thanks,
Acee



From: Lsr <lsr-bounces@ietf.org> on behalf of "Acee Lindem (acee)" <acee=40cisco.com@dmarc.ietf.org>
Date: Friday, May 15, 2020 at 3:40 PM
To: "lsr@ietf.org" <lsr@ietf.org>
Subject: [Lsr] Flooding Topology Computation Algorithm - draft-cc-lsr-flooding-reduction-08 Working Group Adoption Call



This begins a 3 week (due to holidays) WG adoption call for the “Flooding Topology Computation Algorithm” draft. Please issue your support or objection to this list by 11:59 PM, UTC on June 5th, 2020. Here is a URL for your convenience.



https://datatracker.ietf.org/doc/draft-cc-lsr-flooding-reduction/<https://nam11.safelinks.protection.outlook.com/?url=https%3A%2F%2Fdatatracker.ietf.org%2Fdoc%2Fdraft-cc-lsr-flooding-reduction%2F&data=02%7C01%7Chuaimo.chen%40futurewei.com%7C41eead7b49484332128d08d80987e8b8%7C0fee8ff2a3b240189c753a1d5591fedc%7C1%7C0%7C637269826621073729&sdata=mScDoVdFmFXGhPmKPfq0jG5fgJub4Sb8abZ4%2BVVQzVk%3D&reserved=0>



Thanks,
Acee