RE: Size of CR in CRH

Ron Bonica <rbonica@juniper.net> Thu, 21 May 2020 14:34 UTC

Return-Path: <rbonica@juniper.net>
X-Original-To: ipv6@ietfa.amsl.com
Delivered-To: ipv6@ietfa.amsl.com
Received: from localhost (localhost [127.0.0.1]) by ietfa.amsl.com (Postfix) with ESMTP id 820543A09D9 for <ipv6@ietfa.amsl.com>; Thu, 21 May 2020 07:34:30 -0700 (PDT)
X-Virus-Scanned: amavisd-new at amsl.com
X-Spam-Flag: NO
X-Spam-Score: -2.1
X-Spam-Level:
X-Spam-Status: No, score=-2.1 tagged_above=-999 required=5 tests=[BAYES_00=-1.9, DKIMWL_WL_HIGH=-0.001, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, 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=gct02dZK; dkim=pass (1024-bit key) header.d=juniper.net header.b=MjZLN83I
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 d6xwHm9cNpju for <ipv6@ietfa.amsl.com>; Thu, 21 May 2020 07:34:27 -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 98F7E3A09D3 for <6man@ietf.org>; Thu, 21 May 2020 07:34:27 -0700 (PDT)
Received: from pps.filterd (m0108160.ppops.net [127.0.0.1]) by mx0b-00273201.pphosted.com (8.16.0.42/8.16.0.42) with SMTP id 04LERGVF003099; Thu, 21 May 2020 07:34:10 -0700
DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=juniper.net; h=from : to : cc : subject : date : message-id : references : in-reply-to : content-type : content-transfer-encoding : mime-version; s=PPS1017; bh=yAHBX6y+xZ5TtlOqL0aOix3wGw85PciVjVjXjSfARQQ=; b=gct02dZKVLwLl5a/l+4xiKc4hFmhSER7IINJNWtjixPeXnWC6shVt99I7Pta7WXQtics vLk3g3906/oE8x8hWS7ohggsWMmaZwFYGAVUnyxiBV901Riw3LDwKCV0JgxJXdFfzFe0 M1cJv3QZ65R2smzpIjaMIbaYYBswH06qq9OzvQYXKeYnWuwF7ktQoGCLsNZSMt+/c8TV ld906T0TK6TM9QiXennjHBpEswsGsKO1wEZsrc/G79EVaujKTWK7Jty6NqcuGVkqYxru eCD0fKAoDIoLUGhC816bYJ2HwiuRj7bRag03o9ZAGj81mlCBix/kT0arcK1HWNCfEUto BA==
Received: from nam10-mw2-obe.outbound.protection.outlook.com (mail-mw2nam10lp2100.outbound.protection.outlook.com [104.47.55.100]) by mx0b-00273201.pphosted.com with ESMTP id 312e3hhpx2-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Thu, 21 May 2020 07:34:10 -0700
ARC-Seal: i=1; a=rsa-sha256; s=arcselector9901; d=microsoft.com; cv=none; b=L2KN/zAzef1GZ6krBhVqZ5cxa2O4NAxmlL6wUb/s5/M1GMMoNrCCEZOqS8Le2ZWxK5DcIUCAJfIl3fLkGcjNR91aGh7putPF+Fh3X8Zt4CAz3Jx58Dt4BHmigjFfQP9FxAtfb1ayvOzlCCVO6MSlCp9fzQpGcnZHQ31cNU74odVc8GTESSq04L03hN1TYQ50g//ZRfGoT4/QoFjJM7W4rQSdOAmvxh/N6xYUBn+vrGp7tc0JQinTzdowdUCqq+U1Sbq05C/kX5dRB/WEuXJ9VkF5DP2lbeHxeZ2/fge1/LfWrqc2ijFEaVP/vNRUGgMqdbTpyIKZNnSv9wP2QzuqPA==
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=yAHBX6y+xZ5TtlOqL0aOix3wGw85PciVjVjXjSfARQQ=; b=gAho3nC380gIr/baMvN4uw26jyfR6uW7/5EUGmGjnibdT44W/5s30XMw8rRClM+ytK8UIf9OYnBh/3xJDjPZYLwBAkbDmsdH67v2tJJ+FnjINVVCs4CughH4JMqitGAvQ8ep4WpWp3FZGOk5wmylInkvJhJgJjPFqmELOh4CYhcGXMi9AOnwyyUvhJTDx/ACPfr4t7EKYVpV9jli/qPRHugbCh/F6+oQIyjQ0W/qJUnRq6niOCzVtnTCZ5MfY9gHveC0VZh9CSWXQViM3fNwep5h4Nex0lLA9OeLLGUUwCtIhM6qs1HgHYMy+S2Mg18wGsntcjqIYzVOB08YY5rBwA==
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=yAHBX6y+xZ5TtlOqL0aOix3wGw85PciVjVjXjSfARQQ=; b=MjZLN83In/07oNh5vwz93V8O4IkTtr5S59X6IxySfKJNxcqsfAqn5BUsvsVdGb+73mSQJ7bJCY5Hbns7y7cAw7+H01iGuA7TgFrwhBHn9rXSNiPnPrah7kLBxK9TC4DHU6k8gUJUjNgTLY0ZAxXlW2UeTTDZsp3+63Rg2nEt2no=
Received: from DM6PR05MB6348.namprd05.prod.outlook.com (2603:10b6:5:122::15) by DM6PR05MB5914.namprd05.prod.outlook.com (2603:10b6:5:106::14) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.20.3021.12; Thu, 21 May 2020 14:34:08 +0000
Received: from DM6PR05MB6348.namprd05.prod.outlook.com ([fe80::c020:3bf5:7230:75e3]) by DM6PR05MB6348.namprd05.prod.outlook.com ([fe80::c020:3bf5:7230:75e3%4]) with mapi id 15.20.3021.019; Thu, 21 May 2020 14:34:08 +0000
From: Ron Bonica <rbonica@juniper.net>
To: Nick Hilliard <nick@foobar.org>
CC: 6man <6man@ietf.org>
Subject: RE: Size of CR in CRH
Thread-Topic: Size of CR in CRH
Thread-Index: AdYvFTreFKnyM7AmR8qG9Oc9YkopMAABO0PwAA/1AwAACJdfgA==
Date: Thu, 21 May 2020 14:34:07 +0000
Message-ID: <DM6PR05MB63489BBE50753D518C887908AEB70@DM6PR05MB6348.namprd05.prod.outlook.com>
References: <C7C2E1C43D652C4E9E49FE7517C236CB02A2BA5D@dggeml529-mbx.china.huawei.com> <DM6PR05MB634888D7D912D561B7F5F0E8AEB70@DM6PR05MB6348.namprd05.prod.outlook.com> <c7b12240-21dd-bb4c-99b6-d590bc298934@foobar.org>
In-Reply-To: <c7b12240-21dd-bb4c-99b6-d590bc298934@foobar.org>
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_SetDate=2020-05-21T14:34:06Z; 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=fe3aaf44-3987-4138-8bf3-9c91e3a2be09; MSIP_Label_0633b888-ae0d-4341-a75f-06e04137d755_ContentBits=2
dlp-product: dlpe-windows
dlp-version: 11.4.0.45
dlp-reaction: no-action
authentication-results: foobar.org; dkim=none (message not signed) header.d=none;foobar.org; dmarc=none action=none header.from=juniper.net;
x-originating-ip: [108.28.233.91]
x-ms-publictraffictype: Email
x-ms-office365-filtering-ht: Tenant
x-ms-office365-filtering-correlation-id: d9e0006e-b2ce-423e-35e2-08d7fd940537
x-ms-traffictypediagnostic: DM6PR05MB5914:
x-microsoft-antispam-prvs: <DM6PR05MB59141CB2C762AB939DDAC3C0AEB70@DM6PR05MB5914.namprd05.prod.outlook.com>
x-ms-oob-tlc-oobclassifiers: OLM:8273;
x-forefront-prvs: 041032FF37
x-ms-exchange-senderadcheck: 1
x-microsoft-antispam: BCL:0;
x-microsoft-antispam-message-info: lc3TYSp5jkB4g1dMpVm9MzB4tBV22oTdz2XfjtH/p/Ycmup3XAiPv54yKSWtkDkqcI71GOueFK+AcPhqDXCCqYz5/WM5TZx2aftTsbHFwUrdYfRSG6FmNK+GlbseMJxitXJPBJftVUxrJbxVe04QQ91sb9GC/IOd2bWnCYeooikFZ45PhMSu3T7CLW22904iybSwK37dnb6ZsV6F9JVwW/DtCzPn9rZY1MYXQ244aTE2T32ZdCUkMWU5wgfonOcUOyzRiDi+dHTrGnpnldO7cd5UbZX3ku+UbzTG/w4yJkyVe0Jw47JmUI5XRb7EmvoDIBp4hY3lLObfir+3U4TFWQ==
x-forefront-antispam-report: CIP:255.255.255.255; CTRY:; LANG:en; SCL:1; SRV:; IPV:NLI; SFV:NSPM; H:DM6PR05MB6348.namprd05.prod.outlook.com; PTR:; CAT:NONE; SFTY:; SFS:(4636009)(346002)(396003)(376002)(366004)(136003)(39860400002)(66446008)(316002)(33656002)(478600001)(9686003)(55016002)(6916009)(64756008)(2906002)(4326008)(7696005)(86362001)(26005)(52536014)(66946007)(76116006)(71200400001)(6506007)(53546011)(186003)(66476007)(5660300002)(8676002)(66556008)(8936002); DIR:OUT; SFP:1102;
x-ms-exchange-antispam-messagedata: 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
x-ms-exchange-transport-forked: True
Content-Type: text/plain; charset="utf-8"
Content-Transfer-Encoding: base64
MIME-Version: 1.0
X-OriginatorOrg: juniper.net
X-MS-Exchange-CrossTenant-Network-Message-Id: d9e0006e-b2ce-423e-35e2-08d7fd940537
X-MS-Exchange-CrossTenant-originalarrivaltime: 21 May 2020 14:34:07.9636 (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: a1QQmcR+Qh5lr88+Ton9nvt2B5osRjvZpMND9QosDpNvZLoPj+tje8jErJ5WawyozzaTpbabRuXEcYZ6ASBpZA==
X-MS-Exchange-Transport-CrossTenantHeadersStamped: DM6PR05MB5914
X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10434:6.0.216, 18.0.676 definitions=2020-05-21_08:2020-05-21, 2020-05-21 signatures=0
X-Proofpoint-Spam-Details: rule=outbound_spam_notspam policy=outbound_spam score=0 mlxscore=0 adultscore=0 phishscore=0 lowpriorityscore=0 malwarescore=0 mlxlogscore=999 clxscore=1015 spamscore=0 impostorscore=0 cotscore=-2147483648 bulkscore=0 suspectscore=0 priorityscore=1501 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2004280000 definitions=main-2005210109
Archived-At: <https://mailarchive.ietf.org/arch/msg/ipv6/w8PFc_2Do56VOYNWBfWeK0MU_pw>
X-BeenThere: ipv6@ietf.org
X-Mailman-Version: 2.1.29
Precedence: list
List-Id: "IPv6 Maintenance Working Group \(6man\)" <ipv6.ietf.org>
List-Unsubscribe: <https://www.ietf.org/mailman/options/ipv6>, <mailto:ipv6-request@ietf.org?subject=unsubscribe>
List-Archive: <https://mailarchive.ietf.org/arch/browse/ipv6/>
List-Post: <mailto:ipv6@ietf.org>
List-Help: <mailto:ipv6-request@ietf.org?subject=help>
List-Subscribe: <https://www.ietf.org/mailman/listinfo/ipv6>, <mailto:ipv6-request@ietf.org?subject=subscribe>
X-List-Received-Date: Thu, 21 May 2020 14:34:31 -0000

Nick,

Fair enough. Let's initiate a dialog to identify and mitigate the operational complexity. This may require many messages, so let's do that off-line and come back to the mailing list with a summary.

                                                                 Ron



Juniper Business Use Only

-----Original Message-----
From: Nick Hilliard <nick@foobar.org> 
Sent: Thursday, May 21, 2020 6:24 AM
To: Ron Bonica <rbonica@juniper.net>
Cc: 6man <6man@ietf.org>
Subject: Re: Size of CR in CRH

[External Email. Be cautious of content]


Ron Bonica wrote on 21/05/2020 03:51:
> Does having two CRH versions really add operational complexity, given 
> that operators will be advised to run one or another?
>
> Why not let the operator choose which version is best for its network? 
> They probably know better than us.

yeah, it really does add complexity.

I don't see a straightforward way of hiding the implementation details in a configuration grammar, at least not portably across vendors.  This means implementing complexity right down the tool chain and creating operational / support awareness about the fact there would be N different varieties of CRH, semantically similar but not the same.

If you merge networks with different SID sizes, this will be disruptive because there's no clear migration mechanism between one size and another, so changing SID size would mean a flag day. Probably retooling too.

It's not just operational complexity, btw - using multiple SID sizes has a long trail of consequences at a protocol level too.  For example, how would you signal this in bgp?  Separate afis?  Same AFI but different tlvs for each different type? Then how do you handle arbitrage?  Tom made some suggestions, but these also have consequences.

If the prevailing WG opinion is to make multiple SID size options available, then we need to describe in detail how this is going to work right across the board, and how to minimise the downstream impact.  If we don't then this pushes the consequence heap into other peoples' laps and they may not appreciate this.

Nick