[Idr] Clarification on usage of NHC
Srihari Sangli <ssangli@juniper.net> Mon, 22 July 2024 19:18 UTC
Return-Path: <ssangli@juniper.net>
X-Original-To: idr@ietfa.amsl.com
Delivered-To: idr@ietfa.amsl.com
Received: from localhost (localhost [127.0.0.1]) by ietfa.amsl.com (Postfix) with ESMTP id 1DBD5C180B6D for <idr@ietfa.amsl.com>; Mon, 22 Jul 2024 12:18:34 -0700 (PDT)
X-Virus-Scanned: amavisd-new at amsl.com
X-Spam-Flag: NO
X-Spam-Score: -2.251
X-Spam-Level:
X-Spam-Status: No, score=-2.251 tagged_above=-999 required=5 tests=[BAYES_00=-1.9, DKIMWL_WL_HIGH=-0.148, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, HTML_MESSAGE=0.001, RCVD_IN_ZEN_BLOCKED_OPENDNS=0.001, SPF_HELO_NONE=0.001, SPF_NONE=0.001, T_SCC_BODY_TEXT_LINE=-0.01, URIBL_BLOCKED=0.001, URIBL_DBL_BLOCKED_OPENDNS=0.001, URIBL_ZEN_BLOCKED_OPENDNS=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="Wdxg7/JI"; dkim=neutral reason="invalid (public key: not available)" header.d=juniper.net header.b="Y4J4cYRB"
Received: from mail.ietf.org ([50.223.129.194]) by localhost (ietfa.amsl.com [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id 3nChhs0zQG3k for <idr@ietfa.amsl.com>; Mon, 22 Jul 2024 12:18:30 -0700 (PDT)
Received: from mx0a-00273201.pphosted.com (mx0a-00273201.pphosted.com [208.84.65.16]) (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 76465C17C8B6 for <idr@ietf.org>; Mon, 22 Jul 2024 12:18:30 -0700 (PDT)
Received: from pps.filterd (m0108156.ppops.net [127.0.0.1]) by mx0a-00273201.pphosted.com (8.18.1.2/8.18.1.2) with ESMTP id 46MC5BvD022763 for <idr@ietf.org>; Mon, 22 Jul 2024 12:18:30 -0700
DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=juniper.net; h= content-type:date:from:message-id:mime-version:subject:to; s= PPS1017; bh=pGIKuFvjhJO7llUpZOw75dKk3r+98azwv/QIudZFu6c=; b=Wdxg 7/JIvUzlrfr6KWOC5jSp5uvXbAe1srrCwtncyyAC3RYod2fhREAZyCWVZQ/Cbcdn RisU+abh0S1FB7qOffQroileio64DGlChxQzYjYFG6ksIXD2G/zuKaZ2+VoBXYl2 aN8KRM7ZcR7MYKvfLNJjCwgB/80k1dP7bcFzZwH42qv1PRto8CO27oxwElWtVP2I usBk5xbrJKcrYJPZfG/Wi6O0rMdXdUHXilBAA7J/DC8k00+uErEyRiFx1c6hVuBm hqSbLSuwY/Js5xT0mOyrUgQjOU0H5JIKrElGun4IORkMhbn7i5ypZmhY3P17CtHi jFZ64Jg2JGLRHJtd2Q==
Received: from dm1pr04cu001.outbound.protection.outlook.com (mail-centralusazlp17010006.outbound.protection.outlook.com [40.93.13.6]) by mx0a-00273201.pphosted.com (PPS) with ESMTPS id 40gc8eubhu-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT) for <idr@ietf.org>; Mon, 22 Jul 2024 12:18:29 -0700 (PDT)
ARC-Seal: i=1; a=rsa-sha256; s=arcselector10001; d=microsoft.com; cv=none; b=sXdd9xOuIkQySX7hH6yqWHDFdH+Ip4ld5/3PLnbMtKdVkhALpbnq+c3B7SyfE6ZHZfRnfyx5P2WfevgtaNinZiyjluBDtIcXwqY1PdoDFqAOBJbgX+LayVjGZzo/iocLj/cH4NH6cGPlSKNvGGaRweYp6/GbI/K2opmeUWfD/o71FVIURMx3jEG81z40O0jkkCr8cwho92dHZrXsIsn6GbRUUJiAmWB3S7y/bqqm9VS78/TNRqZXaxo8Nkrkqy+PFdi1mwUbbA4useo5VVx6Lkp/QPbhJPHV//gxaf17P94NtWP6kDBynbvRjGuLbYMOel1/sWCGluuu9xeyruUM4g==
ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=microsoft.com; s=arcselector10001; h=From:Date:Subject:Message-ID:Content-Type:MIME-Version:X-MS-Exchange-AntiSpam-MessageData-ChunkCount:X-MS-Exchange-AntiSpam-MessageData-0:X-MS-Exchange-AntiSpam-MessageData-1; bh=pGIKuFvjhJO7llUpZOw75dKk3r+98azwv/QIudZFu6c=; b=wos5c9uS9k0yPCfh9uJvHt60P8rs+GsRH1SyUXq5ZqAzxlIuRqS2WxMzInI/ZB7i2RBwmIdAUwweElgVE5S9XB6N+w9Dzwy1jgTerXPmAxEFdnGD7GJDKEMIdptgtiYKI+WHSfjMiGB6eA6DWBRj35dZ22T5nMXqq6DmFZDHVe84D1yYoj7YCkOGVsLYwj9/vSOItEW1fKyffpCKtHblYUz4oopYPNdehVVoUezWRkDn5kM5tUUV260SHr1WGxhdARKHHwg+IsySX9xUNt7DVevM4JB7n+C9h/2TRMH0fdpA/8Raf+0jQh29twVvyXmpT3oYGFDjoYmMbylBHbZYHA==
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=pGIKuFvjhJO7llUpZOw75dKk3r+98azwv/QIudZFu6c=; b=Y4J4cYRBAIfi7ximCPLgwdxeR+kViqT/W114jaA31sNcIhVfjWyd8G3Go+PjAtORrvCM0iGV/QTaURueuztLnQz77CC4SrGrO1PIcbZy8jLXBzIGJ5A78D1R9qPzOWb1TlGDFkgT9wPH0Iggt8wZuyOe8s6VUz1hToGPe2XBfQc=
Received: from PH0PR05MB7749.namprd05.prod.outlook.com (2603:10b6:510:2e::7) by SA1PR05MB7886.namprd05.prod.outlook.com (2603:10b6:806:1a2::8) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.20.7784.16; Mon, 22 Jul 2024 19:18:26 +0000
Received: from PH0PR05MB7749.namprd05.prod.outlook.com ([fe80::1cae:3cc0:347a:edf1]) by PH0PR05MB7749.namprd05.prod.outlook.com ([fe80::1cae:3cc0:347a:edf1%5]) with mapi id 15.20.7784.016; Mon, 22 Jul 2024 19:18:26 +0000
From: Srihari Sangli <ssangli@juniper.net>
To: "idr@ietf.org" <idr@ietf.org>
Thread-Topic: Clarification on usage of NHC
Thread-Index: AQHa3GNoLRT7NtWJtEmiP2vB61k4uQ==
Date: Mon, 22 Jul 2024 19:18:25 +0000
Message-ID: <PH0PR05MB7749AF6440DF76A8478E0B62B9A82@PH0PR05MB7749.namprd05.prod.outlook.com>
Accept-Language: en-US
Content-Language: en-US
X-MS-Has-Attach:
X-MS-TNEF-Correlator:
msip_labels: MSIP_Label_0633b888-ae0d-4341-a75f-06e04137d755_Enabled=True;MSIP_Label_0633b888-ae0d-4341-a75f-06e04137d755_SiteId=bea78b3c-4cdb-4130-854a-1d193232e5f4;MSIP_Label_0633b888-ae0d-4341-a75f-06e04137d755_SetDate=2024-07-22T18:17:27.8575361Z;MSIP_Label_0633b888-ae0d-4341-a75f-06e04137d755_ContentBits=0;MSIP_Label_0633b888-ae0d-4341-a75f-06e04137d755_Method=Standard
x-ms-publictraffictype: Email
x-ms-traffictypediagnostic: PH0PR05MB7749:EE_|SA1PR05MB7886:EE_
x-ms-office365-filtering-correlation-id: 53272825-44a2-44e8-54ca-08dcaa830fa8
x-ms-exchange-senderadcheck: 1
x-ms-exchange-antispam-relay: 0
x-microsoft-antispam: BCL:0;ARA:13230040|1800799024|366016|376014|38070700018;
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:PH0PR05MB7749.namprd05.prod.outlook.com;PTR:;CAT:NONE;SFS:(13230040)(1800799024)(366016)(376014)(38070700018);DIR:OUT;SFP:1102;
x-ms-exchange-antispam-messagedata-chunkcount: 1
x-ms-exchange-antispam-messagedata-0: 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
Content-Type: multipart/alternative; boundary="_000_PH0PR05MB7749AF6440DF76A8478E0B62B9A82PH0PR05MB7749namp_"
MIME-Version: 1.0
X-OriginatorOrg: juniper.net
X-MS-Exchange-CrossTenant-AuthAs: Internal
X-MS-Exchange-CrossTenant-AuthSource: PH0PR05MB7749.namprd05.prod.outlook.com
X-MS-Exchange-CrossTenant-Network-Message-Id: 53272825-44a2-44e8-54ca-08dcaa830fa8
X-MS-Exchange-CrossTenant-originalarrivaltime: 22 Jul 2024 19:18:25.9678 (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: ihR3f3YghIkRhWObC/gMY5zW/nSc2pdUzRW3miZdCwhV22AR2QB0Ac7rWQdiR2GlzA2XQc67njsRU6WlxQy89A==
X-MS-Exchange-Transport-CrossTenantHeadersStamped: SA1PR05MB7886
X-Proofpoint-GUID: sS6mBe8RWiJjQRc3owvYn3S5A9CK8RUk
X-Proofpoint-ORIG-GUID: sS6mBe8RWiJjQRc3owvYn3S5A9CK8RUk
X-Proofpoint-Virus-Version: vendor=baseguard engine=ICAP:2.0.293,Aquarius:18.0.1039,Hydra:6.0.680,FMLib:17.12.28.16 definitions=2024-07-22_13,2024-07-22_01,2024-05-17_01
X-Proofpoint-Spam-Details: rule=outbound_spam_notspam policy=outbound_spam score=0 phishscore=0 malwarescore=0 spamscore=0 mlxlogscore=803 mlxscore=0 lowpriorityscore=0 impostorscore=0 clxscore=1015 priorityscore=1501 suspectscore=0 adultscore=0 bulkscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.19.0-2407110000 definitions=main-2407220144
Message-ID-Hash: GMUG4OAFIASQEV4PF2XB6ZFW3KIF76BJ
X-Message-ID-Hash: GMUG4OAFIASQEV4PF2XB6ZFW3KIF76BJ
X-MailFrom: ssangli@juniper.net
X-Mailman-Rule-Misses: dmarc-mitigation; no-senders; approved; emergency; loop; banned-address; member-moderation; header-match-idr.ietf.org-0; nonmember-moderation; administrivia; implicit-dest; max-recipients; max-size; news-moderation; no-subject; digests; suspicious-header
X-Mailman-Version: 3.3.9rc4
Precedence: list
Subject: [Idr] Clarification on usage of NHC
List-Id: Inter-Domain Routing <idr.ietf.org>
Archived-At: <https://mailarchive.ietf.org/arch/msg/idr/RJBato0xe7e3GdLhBVOGX6qSIPY>
List-Archive: <https://mailarchive.ietf.org/arch/browse/idr>
List-Help: <mailto:idr-request@ietf.org?subject=help>
List-Owner: <mailto:idr-owner@ietf.org>
List-Post: <mailto:idr@ietf.org>
List-Subscribe: <mailto:idr-join@ietf.org>
List-Unsubscribe: <mailto:idr-leave@ietf.org>
HI, Folks: Regarding the question on NHC, its transitivity and how contents of NHC (including AMetric) would be advertised at EBGP boundary, please see below. NHC is optional & transitive and AMetric is leveraging that attribute to propagate the accumulated metric. At every router that modifies next hop, NHC procedures says that next hop field needs to be updated and NHC contents need to be recreated. If any capability is not supported, it should be dropped from advertisement. At EBGP boundary, the NHC is advertised unless explicitly disallowed. AMetric leverages NHC and clarifies, customizes the above procedure – at any non-originating router that modifies next hop, received AMetric should be preserved and updated : New AMetric metric-value = received AMetric metric-value + local domain cost to next hop and (2) metric-flags should be updated with appropriate “D” or “N” bit setting. Keyur and others, I hope this answers your question. Thanks Ketan to clarify at the mic. Thanks & Regards, srihari… Juniper Business Use Only
- [Idr] Clarification on usage of NHC Srihari Sangli