Re: [Idr] draft-ietf-idr-ext-opt-param-06.txt - 2 Week WG LC (7/30 to 8/13/2019)

John Scudder <jgs@juniper.net> Fri, 09 August 2019 19:03 UTC

Return-Path: <jgs@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 743AE120254 for <idr@ietfa.amsl.com>; Fri, 9 Aug 2019 12:03:39 -0700 (PDT)
X-Virus-Scanned: amavisd-new at amsl.com
X-Spam-Flag: NO
X-Spam-Score: -2.701
X-Spam-Level:
X-Spam-Status: No, score=-2.701 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, RCVD_IN_DNSWL_LOW=-0.7, SPF_HELO_NONE=0.001, SPF_PASS=-0.001] autolearn=ham autolearn_force=no
Authentication-Results: ietfa.amsl.com (amavisd-new); dkim=pass (2048-bit key) header.d=juniper.net
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 uAdc1g4dBaSN for <idr@ietfa.amsl.com>; Fri, 9 Aug 2019 12:03:37 -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 43F1C1201E5 for <idr@ietf.org>; Fri, 9 Aug 2019 12:03:37 -0700 (PDT)
Received: from pps.filterd (m0108162.ppops.net [127.0.0.1]) by mx0b-00273201.pphosted.com (8.16.0.27/8.16.0.27) with SMTP id x79Ixn77030808; Fri, 9 Aug 2019 12:03:34 -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 : content-id : content-transfer-encoding : mime-version; s=PPS1017; bh=r344X3HXSr6wW4CGHvoqWiS3eEgr8eUnZ0LrEZayej0=; b=YVdXEpjz0UIAMWkN8HS1uN1i+WW8S33Y0iCB4AtLGPFcY3+sGlHobyYgi6c/1lpldk7A 8uBtjTA39ZL8/v1Pdtdm1vnfuJix8BhsTJR9sepj9+xw0wL5AFpHKgrzlaIVvVJjb7Aq TJ4FqqCSQ34sme9PmOjEeyrev8wWOcwhFMirv+/JDiJe/erEAeIzxOjcNm45jQdnMB8C vf8poMld73+8SvG2T8DNItXUsjClxKNVlKbEnoAncjh4tRAvnN6CENo7pORnzBGFeWTL XCF4XQFUak9VhL4wQ+Zc7KbnLd2sWMFnwCCjo2U+8zDTd+yujzPqqsOHLHuUaI7mBHND QQ==
Received: from nam04-bn3-obe.outbound.protection.outlook.com (mail-bn3nam04lp2050.outbound.protection.outlook.com [104.47.46.50]) by mx0b-00273201.pphosted.com with ESMTP id 2u98rfrms0-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Fri, 09 Aug 2019 12:03:34 -0700
ARC-Seal: i=1; a=rsa-sha256; s=arcselector9901; d=microsoft.com; cv=none; b=X+dUoqPkT4PQYcBCeMGbFwqYJpbEqOL4WSox4pMZ+C11gfZmj30j4tOqc8XspvYNA4uPxd9w4tInmszfZtx64ZbJmx9daTe9Ahttad5Y6LB3cbtMhZKdrFdQencbThuAMEKuxzllL1RYKC+wTbnFpEhC/uLhiyl5o+DmHQATR3YZEMsG0I1pNV6SmuCmEZhfn42lcxJ06ipfJY6ktDJNqIt7vEgl5rahH/Horoi9cwEL/Oa6jc/2bmBrhoQbeXLds6Ff7HdDSGpC1phYW7rgzRy2G0hpgkac3c3ldaH8+YXBa/RhzjZSfQuGl9p5o/RMKd5cbJ6pkQ89gHom5olZqQ==
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=r344X3HXSr6wW4CGHvoqWiS3eEgr8eUnZ0LrEZayej0=; b=jMxO8ht5CO37zixsRMAEbUpsaLi5jvWo82O97l4W9AoIQw6iqVWpDEd2aN3O6oCFfGNblGoicyuOY33JEhXdQg8tr1ELe2Kw4wdykMCmzag1B1DwL5Wk9hSLv1w8OJ89DreFHakHlCijujxBT9ZO7FnOQUVClB+uuywdc8KbZpqO+WUzzYXqYj+HpgGDpYidP5pzg6o2ly+DgRRoO6/H7/H1rLZSpupDtcz+zxk1cjzYBDs3/HQNYTxdOEvgttFH/WxZwOBOalSowZN8KiG4XvkPnl0K5lmwRiN0kfS6sPXfLvAV0gkpLRzPMnxXm1XeyM7uQUSiO6TKccauLYaOEw==
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
Received: from DM5PR05MB3242.namprd05.prod.outlook.com (10.173.220.8) by DM5PR05MB3564.namprd05.prod.outlook.com (10.174.242.157) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.20.2157.13; Fri, 9 Aug 2019 19:03:32 +0000
Received: from DM5PR05MB3242.namprd05.prod.outlook.com ([fe80::4857:412d:b70d:e6db]) by DM5PR05MB3242.namprd05.prod.outlook.com ([fe80::4857:412d:b70d:e6db%11]) with mapi id 15.20.2157.020; Fri, 9 Aug 2019 19:03:32 +0000
From: John Scudder <jgs@juniper.net>
To: Ondrej Zajicek <santiago@crfreenet.org>, idr wg <idr@ietf.org>
Thread-Topic: [Idr] draft-ietf-idr-ext-opt-param-06.txt - 2 Week WG LC (7/30 to 8/13/2019)
Thread-Index: AdVG8AEgtJ8an9KITLaaaGetwJsC1QAAVhgAAcsDRwAAMe72gA==
Date: Fri, 9 Aug 2019 19:03:32 +0000
Message-ID: <9BB06D7E-860B-4864-86B6-85186DD74C5F@juniper.net>
References: <000801d546f0$b9d27310$2d775930$@ndzh.com> <1F967C41-2164-4FB7-813F-9DB41245BE6A@juniper.net> <20190808191346.GA20497@feanor.crfreenet.org>
In-Reply-To: <20190808191346.GA20497@feanor.crfreenet.org>
Accept-Language: en-US
Content-Language: en-US
X-MS-Has-Attach:
X-MS-TNEF-Correlator:
x-originating-ip: [162.225.191.79]
x-ms-publictraffictype: Email
x-ms-office365-filtering-correlation-id: 52e6c452-3583-4218-35cb-08d71cfc45ba
x-ms-office365-filtering-ht: Tenant
x-microsoft-antispam: BCL:0; PCL:0; RULEID:(2390118)(7020095)(4652040)(8989299)(4534185)(4627221)(201703031133081)(201702281549075)(8990200)(5600148)(711020)(4605104)(1401327)(4618075)(2017052603328)(7193020); SRVR:DM5PR05MB3564;
x-ms-traffictypediagnostic: DM5PR05MB3564:
x-microsoft-antispam-prvs: <DM5PR05MB3564EE02E0EDF45AC6BE8244AAD60@DM5PR05MB3564.namprd05.prod.outlook.com>
x-ms-oob-tlc-oobclassifiers: OLM:8882;
x-forefront-prvs: 01244308DF
x-forefront-antispam-report: SFV:NSPM; SFS:(10019020)(4636009)(366004)(396003)(39860400002)(376002)(346002)(136003)(199004)(189003)(11346002)(36756003)(6512007)(110136005)(8676002)(6246003)(316002)(256004)(446003)(6506007)(53546011)(2616005)(486006)(26005)(476003)(25786009)(53936002)(76176011)(102836004)(33656002)(14444005)(14454004)(186003)(99286004)(66556008)(64756008)(229853002)(8936002)(71190400001)(71200400001)(2906002)(478600001)(66946007)(66446008)(66476007)(91956017)(76116006)(6486002)(6116002)(3846002)(305945005)(6436002)(81156014)(81166006)(66066001)(5660300002)(86362001)(7736002); DIR:OUT; SFP:1102; SCL:1; SRVR:DM5PR05MB3564; H:DM5PR05MB3242.namprd05.prod.outlook.com; FPR:; SPF:None; LANG:en; PTR:InfoNoRecords; A:1; MX:1;
received-spf: None (protection.outlook.com: juniper.net does not designate permitted sender hosts)
x-ms-exchange-senderadcheck: 1
x-microsoft-antispam-message-info: N7+0Msgj083EhXJmuSPk4nUt7pcttrNsMlAFtTsUpMjcwX9trCAS8OPMvf7k/Kstk/ovM+qtfwDgcmz6eW4xITuz7ghbxRqBdaN70oFEMwi3SWq7+DZNcSuzTv4NDd8rzOBuYgDm/ysFGzZc7FZGj5BNRz6ycoxHnH89I1Ioto3cwOZH/3kcB1LGVNMZaw2Yizc5A5CcebWgFfAkqzGFY/fboGjsapOczVGyZDVgzT8GkXtRxnvhVkXyjZSwSXeS7RfcfURjMIHclXSbS8Q3Pkhc3n0ocQqig8mUXV/1Lc3jsB894O//To1WTmRBZEZoiVM18aSrkJA3ASYua1NU0e/W4ZolTP4imBlgmTgjyiP+TA2n7fxHqQBTARqcV32A6ZV8dQfNXReVcqLhpwoAUtkKpifHcdbLQx2E73q20RE=
x-ms-exchange-transport-forked: True
Content-Type: text/plain; charset="utf-8"
Content-ID: <53B6815B5946964AB38035294E9D4822@namprd05.prod.outlook.com>
Content-Transfer-Encoding: base64
MIME-Version: 1.0
X-OriginatorOrg: juniper.net
X-MS-Exchange-CrossTenant-Network-Message-Id: 52e6c452-3583-4218-35cb-08d71cfc45ba
X-MS-Exchange-CrossTenant-originalarrivaltime: 09 Aug 2019 19:03:32.2312 (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: PDwpUOisauUoY1XguK9ajBeH8nIg5pD/Cq2V8rCu0dBAgdP0QzFYV67Vi9MPFT/g
X-MS-Exchange-Transport-CrossTenantHeadersStamped: DM5PR05MB3564
X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10434:, , definitions=2019-08-09_06:, , signatures=0
X-Proofpoint-Spam-Details: rule=outbound_spam_notspam policy=outbound_spam score=0 priorityscore=1501 malwarescore=0 suspectscore=0 phishscore=0 bulkscore=0 spamscore=0 clxscore=1011 lowpriorityscore=0 mlxscore=0 impostorscore=0 mlxlogscore=999 adultscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.0.1-1906280000 definitions=main-1908090186
Archived-At: <https://mailarchive.ietf.org/arch/msg/idr/1Uyj_GHt09YRwVXzvpcfbo6m5uA>
Subject: Re: [Idr] draft-ietf-idr-ext-opt-param-06.txt - 2 Week WG LC (7/30 to 8/13/2019)
X-BeenThere: idr@ietf.org
X-Mailman-Version: 2.1.29
Precedence: list
List-Id: Inter-Domain Routing <idr.ietf.org>
List-Unsubscribe: <https://www.ietf.org/mailman/options/idr>, <mailto:idr-request@ietf.org?subject=unsubscribe>
List-Archive: <https://mailarchive.ietf.org/arch/browse/idr/>
List-Post: <mailto:idr@ietf.org>
List-Help: <mailto:idr-request@ietf.org?subject=help>
List-Subscribe: <https://www.ietf.org/mailman/listinfo/idr>, <mailto:idr-request@ietf.org?subject=subscribe>
X-List-Received-Date: Fri, 09 Aug 2019 19:03:51 -0000

Wow. Color me embarrassed, and thank you for pointing this out. I think you are right, and furthermore I think it’s a better solution than what we describe in the draft.

Under the circumstances my suggestion to the WG is that we NOT advance the draft to Proposed Standard. The question would remain what to do with it, keeping in mind there are implementations in the wild. The options I can think of are to abandon it, or to publish it as Historic. So, options on the table for the WG are,

1. Abandon the draft.
2. Publish as Historic, because there are implementations out there.

I think in either of the above cases we would also move code 255 to “deprecated”.

3. Continue forward with the original plan of publishing as Proposed Standard, because ______ (fill in the blank if you support this option).

My preference is option 2, although I confess I might be biased by the sunk cost fallacy. :-/

Thanks again for your observation, Ondrej.

—John

> On Aug 8, 2019, at 3:13 PM, Ondrej Zajicek <santiago@crfreenet.org> wrote:
> 
> On Tue, Jul 30, 2019 at 04:10:49PM +0000, John Scudder wrote:
>> (As a co-author of course.)
>> 
>> Since it seemed helpful last time, here's the elevator pitch for
>> ext-opt-param: We are currently limited to 255 bytes of BGP capabilities.
>> Since many/most BGP extensions want to use a capability, it’s not hard to
>> imagine overrunning the 255 bytes.
> 
> AFAIK we are not currently limited to 255 bytes of BGP capabilities.
> 
> According to RFC 5492, multiple instances of capability options are
> allowed, well-defined, just discouraged:
> 
>   The Capabilities Optional Parameter (OPEN Optional Parameter Type 2)
>   SHOULD only be included in the OPEN message once. ... However,
>   for backward compatibility, a BGP speaker MUST be prepared to receive
>   an OPEN message that contains multiple Capabilities Optional
>   Parameters, each of which contains one or more capabilities TLVs.
> 
> If i want to announce 2k bytes of BGP capabilities, i can just split it
> to multiple sub-256 blocks of capability options. Real limits are 255 bytes
> for each capability and 4k bytes for whole OPEN message.
> 
> While the draft removes per-capability limit by allowing to put all
> capabilities ot one large option, it does that by backward-incompatible way,
> while splitting capabilities to multiple options is backward-compatible.
> 
> -- 
> Elen sila lumenn' omentielvo
> 
> Ondrej 'Santiago' Zajicek (email: santiago@crfreenet.org)
> OpenPGP encrypted e-mails preferred (KeyID 0x11DEADC3, wwwkeys.pgp.net)
> "To err is human -- to blame it on a computer is even more so."