Re: [mpls] MPLS-RT review of draft-ninan-mpls-spring-inter-domain-oam

Shraddha Hegde <shraddha@juniper.net> Mon, 31 May 2021 17:18 UTC

Return-Path: <shraddha@juniper.net>
X-Original-To: mpls@ietfa.amsl.com
Delivered-To: mpls@ietfa.amsl.com
Received: from localhost (localhost [127.0.0.1]) by ietfa.amsl.com (Postfix) with ESMTP id 9891C3A1F47; Mon, 31 May 2021 10:18:14 -0700 (PDT)
X-Virus-Scanned: amavisd-new at amsl.com
X-Spam-Flag: NO
X-Spam-Score: -2.795
X-Spam-Level:
X-Spam-Status: No, score=-2.795 tagged_above=-999 required=5 tests=[BAYES_00=-1.9, DKIMWL_WL_HIGH=-0.698, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, HTML_MESSAGE=0.001, RCVD_IN_DNSWL_BLOCKED=0.001, SPF_HELO_NONE=0.001, SPF_PASS=-0.001, URIBL_BLOCKED=0.001] autolearn=ham autolearn_force=no
Authentication-Results: ietfa.amsl.com (amavisd-new); dkim=pass (2048-bit key) header.d=juniper.net header.b=KZ2g0hS/; dkim=pass (1024-bit key) header.d=juniper.net header.b=exlANAhC
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 OkHOwObDUE8v; Mon, 31 May 2021 10:18:09 -0700 (PDT)
Received: from mx0b-00273201.pphosted.com (mx0b-00273201.pphosted.com [67.231.152.164]) (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 BE5D33A1F41; Mon, 31 May 2021 10:18:08 -0700 (PDT)
Received: from pps.filterd (m0108162.ppops.net [127.0.0.1]) by mx0b-00273201.pphosted.com (8.16.0.43/8.16.0.43) with SMTP id 14VHFWQc015037; Mon, 31 May 2021 10:18:07 -0700
DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=juniper.net; h=from : to : subject : date : message-id : references : in-reply-to : content-type : mime-version; s=PPS1017; bh=2zHoHz2cCSQdMr0d1cB9vhyYuNL4fOSbEggGedajUhc=; b=KZ2g0hS/C88demiGCIeT5qyCtmfhUzHYJWO3uBaOPhN/Cx9wJiyzioMU/FQZfLQJXrnN p78dlvPqBjcw7ovxrJ/pCuz2ZTiLcmqmPoR3AvPnNTneyMDZu2aLLiid8Re6TLJW3Xk/ Qbqeer9ri/hZ+s4xbZ+6n08CGgA1OkoMxCKPPkLpVN9mwi9IFiOjLXbwT79vTTVfZMJG TKXQXyN/CyNAYg3blQK1wqxjbG/B/N5vcR5mdY+7w4ainEPKWj3GVc0Xq4Jg5VAPFnwn oLQmuVb7fKJAI4YjAo0cLz3C3VDoAZ4SGeZY1m+Ll/o196iNE/JDDXdc3BUUZZeAkhAb +g==
Received: from nam10-mw2-obe.outbound.protection.outlook.com (mail-mw2nam10lp2107.outbound.protection.outlook.com [104.47.55.107]) by mx0b-00273201.pphosted.com with ESMTP id 38w16m071d-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Mon, 31 May 2021 10:18:06 -0700
ARC-Seal: i=1; a=rsa-sha256; s=arcselector9901; d=microsoft.com; cv=none; b=KCYykUF4oYwwi4/7lh769URY3JlapUZv77uL3/4IoMdDLAL+v2YO1S+g9N7oHNRVcxcJQltx136pKkN2FISoEiqXr5909M5R5X2yUmQkRQyfRaP6FpO5Y3sNHYLZ/KQ7IHr32VLvTxzADmaYwEZV3nCftfKVLcFzJT2Z36stDYZx3CEW1DeIBvvvrRfAV4Px2bjZhUX27fqKS+cFDr59l/rZ55aIpA+dw5/p6R15pORu+YjyhfunArWlqVhoNBlft7tnLgBCYF57Xjw5kAv+/0jQXG4syipzq5RGX/LF2kBhEKFZSoXrYELxelCpyAvo0QwQ+H3tgJOMYwD1IhSS2w==
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=2zHoHz2cCSQdMr0d1cB9vhyYuNL4fOSbEggGedajUhc=; b=GLQ+0hziu45zKvn62+Y2GdDc+/OKJwCLjasxAkJXlNSY/shY9dWJQ0vPoTIULdkJhxJnQxt/a1Mm1DiLs+Y+EwZ7uz+ras85eAfOZw+DaeDA7z9XZZV/kOrpErfb86a9+bdSjl4/mNKnL8C051iKJT1znksQwfEEgmDJfEPHfdLtxQbDLXwkxIycIoRIVUGHRT8C2GQHqirgsyTLlGYq0xrPDCdwaK9N62N+QWohtIr9owWxxgBojYxtCU5gzuIhtbVJlyEOW1n82vq9V8/P/iwFMj3eNbNyRCIR0brGTZKTLOiCkO4TkvNrojSSNC9ty6aiJy/ge/7bHeq+8hXd9w==
ARC-Authentication-Results: i=1; mx.microsoft.com 1; spf=pass smtp.mailfrom=juniper.net; dmarc=pass action=none header.from=juniper.net; dkim=pass header.d=juniper.net; arc=none
DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=juniper.net; s=selector1; h=From:Date:Subject:Message-ID:Content-Type:MIME-Version:X-MS-Exchange-SenderADCheck; bh=2zHoHz2cCSQdMr0d1cB9vhyYuNL4fOSbEggGedajUhc=; b=exlANAhCKj6sAp0jAUV3Ubtine08mRostxnV1ZLQ+SZQ6GyZ3UA5cmOU9Pjc4E77UiVMYJ1ff14F3yDXgRbZpgIyxVhRBsKlpWax3MsmhLovG4DVXFpp91KvrIQS+EtshnsXi+/wEG20VsVp3BmU3izlQH5mAb4NUprzvMKHYQo=
Received: from CY4PR05MB3576.namprd05.prod.outlook.com (2603:10b6:910:52::22) by CY1PR05MB2681.namprd05.prod.outlook.com (2a01:111:e400:c61c::9) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.20.4195.11; Mon, 31 May 2021 17:18:02 +0000
Received: from CY4PR05MB3576.namprd05.prod.outlook.com ([fe80::2cb6:435f:f75b:1602]) by CY4PR05MB3576.namprd05.prod.outlook.com ([fe80::2cb6:435f:f75b:1602%6]) with mapi id 15.20.4195.017; Mon, 31 May 2021 17:18:02 +0000
From: Shraddha Hegde <shraddha@juniper.net>
To: "gregory.mirsky@ztetx.com" <gregory.mirsky@ztetx.com>, "loa@pi.nu" <loa@pi.nu>, "mpls@ietf.org" <mpls@ietf.org>, "draft-ninan-mpls-spring-inter-domain-oam@ietf.org" <draft-ninan-mpls-spring-inter-domain-oam@ietf.org>, "mpls-chairs@ietf.org" <mpls-chairs@ietf.org>
Thread-Topic: Re:[mpls] MPLS-RT review of draft-ninan-mpls-spring-inter-domain-oam
Thread-Index: AQHXRjZeL4sL9oUHNUyKmeQScBgbv6rzF68AgAANWACACswc8A==
Date: Mon, 31 May 2021 17:18:02 +0000
Message-ID: <CY4PR05MB3576FD84C94441E35A1EEDD2D53F9@CY4PR05MB3576.namprd05.prod.outlook.com>
References: c2927dd5-0f47-bac3-e401-6442b3f74851@pi.nu, bb574915-b2ea-4e52-c293-9cf99bb15238@gmail.com <202105250409409908240@zte.com.cn>
In-Reply-To: <202105250409409908240@zte.com.cn>
Accept-Language: en-US
Content-Language: en-US
X-MS-Has-Attach: yes
X-MS-TNEF-Correlator:
dlp-product: dlpe-windows
dlp-version: 11.6.100.41
dlp-reaction: no-action
msip_labels: MSIP_Label_0633b888-ae0d-4341-a75f-06e04137d755_Enabled=true; MSIP_Label_0633b888-ae0d-4341-a75f-06e04137d755_SetDate=2021-05-31T17:17:58Z; MSIP_Label_0633b888-ae0d-4341-a75f-06e04137d755_Method=Standard; MSIP_Label_0633b888-ae0d-4341-a75f-06e04137d755_Name=0633b888-ae0d-4341-a75f-06e04137d755; MSIP_Label_0633b888-ae0d-4341-a75f-06e04137d755_SiteId=bea78b3c-4cdb-4130-854a-1d193232e5f4; MSIP_Label_0633b888-ae0d-4341-a75f-06e04137d755_ActionId=b6c826a1-bacf-4383-bc8d-98f3d067c10b; MSIP_Label_0633b888-ae0d-4341-a75f-06e04137d755_ContentBits=2
authentication-results: ztetx.com; dkim=none (message not signed) header.d=none;ztetx.com; dmarc=none action=none header.from=juniper.net;
x-originating-ip: [116.197.184.14]
x-ms-publictraffictype: Email
x-ms-office365-filtering-correlation-id: 6a4d89e7-448e-49a3-ed7c-08d924580be2
x-ms-traffictypediagnostic: CY1PR05MB2681:
x-microsoft-antispam-prvs: <CY1PR05MB268146DA8AC2D426CB0A13AFD53F9@CY1PR05MB2681.namprd05.prod.outlook.com>
x-ms-oob-tlc-oobclassifiers: OLM:8882;
x-ms-exchange-senderadcheck: 1
x-microsoft-antispam: BCL:0;
x-microsoft-antispam-message-info: 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
x-forefront-antispam-report: CIP:255.255.255.255; CTRY:; LANG:en; SCL:1; SRV:; IPV:NLI; SFV:NSPM; H:CY4PR05MB3576.namprd05.prod.outlook.com; PTR:; CAT:NONE; SFS:(4636009)(396003)(376002)(366004)(39860400002)(346002)(136003)(2906002)(71200400001)(66946007)(76116006)(33656002)(166002)(53546011)(8676002)(6506007)(66476007)(64756008)(66446008)(66576008)(8936002)(66556008)(7696005)(38100700002)(5660300002)(478600001)(110136005)(122000001)(99936003)(26005)(316002)(52536014)(55016002)(9686003)(86362001)(83380400001)(186003)(9326002); DIR:OUT; SFP:1102;
x-ms-exchange-antispam-messagedata: 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
x-ms-exchange-transport-forked: True
Content-Type: multipart/related; boundary="_005_CY4PR05MB3576FD84C94441E35A1EEDD2D53F9CY4PR05MB3576namp_"; type="multipart/alternative"
MIME-Version: 1.0
X-OriginatorOrg: juniper.net
X-MS-Exchange-CrossTenant-AuthAs: Internal
X-MS-Exchange-CrossTenant-AuthSource: CY4PR05MB3576.namprd05.prod.outlook.com
X-MS-Exchange-CrossTenant-Network-Message-Id: 6a4d89e7-448e-49a3-ed7c-08d924580be2
X-MS-Exchange-CrossTenant-originalarrivaltime: 31 May 2021 17:18:02.3659 (UTC)
X-MS-Exchange-CrossTenant-fromentityheader: Hosted
X-MS-Exchange-CrossTenant-id: bea78b3c-4cdb-4130-854a-1d193232e5f4
X-MS-Exchange-CrossTenant-mailboxtype: HOSTED
X-MS-Exchange-CrossTenant-userprincipalname: 0yJxgfHVFbX7l+ndfn7BhX93ikeyeY5awoQdJXSwac33V0rEDdoeRyh8w0mEeZg//nm76tpXx1ecqprMH7wLdQ==
X-MS-Exchange-Transport-CrossTenantHeadersStamped: CY1PR05MB2681
X-Proofpoint-ORIG-GUID: N2pA5Kr64Tw3TEAtZhTPCiTQ9g3Z-OVt
X-Proofpoint-GUID: N2pA5Kr64Tw3TEAtZhTPCiTQ9g3Z-OVt
X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10434:6.0.391, 18.0.761 definitions=2021-05-31_10:2021-05-31, 2021-05-31 signatures=0
X-Proofpoint-Spam-Details: rule=outbound_spam_notspam policy=outbound_spam score=0 adultscore=0 clxscore=1015 impostorscore=0 suspectscore=0 spamscore=0 malwarescore=0 phishscore=0 mlxscore=0 bulkscore=0 priorityscore=1501 mlxlogscore=999 lowpriorityscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2104190000 definitions=main-2105310129
Archived-At: <https://mailarchive.ietf.org/arch/msg/mpls/bxniEbyyyTy7509qRjPJTLhLrY4>
Subject: Re: [mpls] MPLS-RT review of draft-ninan-mpls-spring-inter-domain-oam
X-BeenThere: mpls@ietf.org
X-Mailman-Version: 2.1.29
Precedence: list
List-Id: Multi-Protocol Label Switching WG <mpls.ietf.org>
List-Unsubscribe: <https://www.ietf.org/mailman/options/mpls>, <mailto:mpls-request@ietf.org?subject=unsubscribe>
List-Archive: <https://mailarchive.ietf.org/arch/browse/mpls/>
List-Post: <mailto:mpls@ietf.org>
List-Help: <mailto:mpls-request@ietf.org?subject=help>
List-Subscribe: <https://www.ietf.org/mailman/listinfo/mpls>, <mailto:mpls-request@ietf.org?subject=subscribe>
X-List-Received-Date: Mon, 31 May 2021 17:18:15 -0000

Hi Greg,

Thanks for the review and comments.

Pls see inline for the reply.



Juniper Business Use Only
From: gregory.mirsky@ztetx.com <gregory.mirsky@ztetx.com>
Sent: Tuesday, May 25, 2021 1:40 AM
To: loa@pi.nu; mpls@ietf.org; draft-ninan-mpls-spring-inter-domain-oam@ietf.org; mpls-chairs@ietf.org
Subject: Re:[mpls] MPLS-RT review of draft-ninan-mpls-spring-inter-domain-oam

[External Email. Be cautious of content]


Dear Authors, WG Chairs, et al.,

I've been asked to review the draft-ninan-mpls-spring-inter-domain-oam. I've concentrated on three criteria:

  1.  clarity of the document
  2.  the technical value of the problem addressed
  3.  technical feasability of the proposed solution

Below are my notes on these three aspects:

  1.  The document is reasonably well-written and is readable.
  2.  I couldn't find a sufficient technical explanation for introducing a new mechanism for the inter-domain ping/traceroute in addition to the one described in RFC 7743<https://urldefense.com/v3/__https:/datatracker.ietf.org/doc/html/rfc7743__;!!NEt6yMaO-gk!VTgakYnhqtUppuq0ACQyr49BeNNYULEBWSJV95zXx24NsknZs8Ec0rZzz4EKFQ58$>.

<Shraddha> Introduction section has some text on how this draft is different from RFC 7743
“   [RFC7743] describes a Echo-relay based solution based on advertising
   a new Relay Node Address Stack TLV containing stack of Echo-relay ip
   addresses.  That mechanism requires the return ping packet to reach

   the control plane on every relay node.”



Basically, RFC 7743 mechanism requires that the relay nodes receive reply packet interpret it and then forward further.

This draft is proposing much simplified solution which does not require control plane involvement on intermediate nodes.

It uses segment routing forwarding plane. I can add some more text to clarify this.



  1.  It seems that the proposed mechanism has several issues:

     *   Three types of SID sub-TLVs are defined, but only use of one is mentioned in the document.
     *   I couldn't find an explanation of the relationship between IPv4/IPv6 Node Address and SID in Type 3 and Type 4 sub-TLVs, respectively
     *   Also, in which scenario the SID field in Type 3 and Type 4 sub-TLVs is recommended?

<Shraddha> Type 3 and type 4 is useful when the SRGB of the  remote node is not available on the headend/PMS that is constructing the return path TLV.

                      The IPv4 node address is used by the receiving node to create mpls label from it’s own SRGB.  The SID is optional. It can be added if the PMS/headend knows the

                      SID. There is no strong usecase for the optional SID field. These TLV structure are directly derived from the SR policy TLV structures in order to be consistent with the

                        Segment routing conventions of describing a path.

I’ll add a new section to describe this.

     *   And further, traceroute mode is called out of the scope of RFC 7743. I've read the explanation of traceroute in the draft, and I don't think it is a workable solution.

<Shraddha> The draft defines two different solutions for trace route. The headend/PMS constructed is define in sec 7.2 and the dynamically constructed return path

                      Described in section 8. Which one are you saying isn’t workable? Also would be helpful if you can specify details of why you think it will not work.

I don't feel that the draft is ready for WG adoption at this point.

I much appreciate your consideration of my comments and looking forward to discussing them with the authors.



Regards,

Greg Mirsky



Sr. Standardization Expert
预研标准部/有线研究院/有线产品经营部 Standard Preresearch Dept./Wireline Product R&D Institute/Wireline Product Operation Division


[cid:image001.gif@01D7566D.FB183290]
[cid:image002.gif@01D7566D.FB183290]
E: gregory.mirsky@ztetx.com<mailto:gregory.mirsky@ztetx.com>
www.zte.com.cn<https://urldefense.com/v3/__http:/www.zte.com.cn/__;!!NEt6yMaO-gk!VTgakYnhqtUppuq0ACQyr49BeNNYULEBWSJV95zXx24NsknZs8Ec0rZzz2FEIVnD$>