Re: [ippm] Adoption call for draft-mizrahi-ippm-ioam-flags Re: Regarding draft-mizrahi-ippm-ioam-flags

"Frank Brockners (fbrockne)" <fbrockne@cisco.com> Fri, 02 August 2019 06:48 UTC

Return-Path: <fbrockne@cisco.com>
X-Original-To: ippm@ietfa.amsl.com
Delivered-To: ippm@ietfa.amsl.com
Received: from localhost (localhost [127.0.0.1]) by ietfa.amsl.com (Postfix) with ESMTP id A83A812008A; Thu, 1 Aug 2019 23:48:05 -0700 (PDT)
X-Virus-Scanned: amavisd-new at amsl.com
X-Spam-Flag: NO
X-Spam-Score: -14.501
X-Spam-Level:
X-Spam-Status: No, score=-14.501 tagged_above=-999 required=5 tests=[BAYES_00=-1.9, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, RCVD_IN_DNSWL_HI=-5, SPF_PASS=-0.001, USER_IN_DEF_DKIM_WL=-7.5] autolearn=ham autolearn_force=no
Authentication-Results: ietfa.amsl.com (amavisd-new); dkim=pass (1024-bit key) header.d=cisco.com header.b=ODXC4kDa; dkim=pass (1024-bit key) header.d=cisco.onmicrosoft.com header.b=Uw9LhnLJ
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 a861MbaW2oaH; Thu, 1 Aug 2019 23:48:02 -0700 (PDT)
Received: from rcdn-iport-3.cisco.com (rcdn-iport-3.cisco.com [173.37.86.74]) (using TLSv1.2 with cipher DHE-RSA-SEED-SHA (128/128 bits)) (No client certificate requested) by ietfa.amsl.com (Postfix) with ESMTPS id 2550F120136; Thu, 1 Aug 2019 23:48:02 -0700 (PDT)
DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=cisco.com; i=@cisco.com; l=16000; q=dns/txt; s=iport; t=1564728482; x=1565938082; h=from:to:cc:subject:date:message-id:references: in-reply-to:content-transfer-encoding:mime-version; bh=dhwcdi5WrOW7tgcm4lQiUXLYu6Blb3DLSimFbyFvtNg=; b=ODXC4kDahhrzT8FCTvIa+fLWhGJnRKpAlQqYsOM349NfpX8t3TjkY+Z7 EiStI3WpWLkVXa5M57AyWL88XmZXr1Zoc3jdGJmhyk3lRTOj+67eQ5tDl HuolW3t/GChwrZyUo99TQDvfy7QDLGeF1NQWnVp2a4I7njhPsGU9+lHqD 4=;
IronPort-PHdr: =?us-ascii?q?9a23=3A9kuBdRQPKpqgy8qqkgM8/4C6UNpsv++ubAcI9p?= =?us-ascii?q?oqja5Pea2//pPkeVbS/uhpkESXBNfA8/wRje3QvuigQmEG7Zub+FE6OJ1XH1?= =?us-ascii?q?5g640NmhA4RsuMCEn1NvnvOiIwBsNJV1lo13q6KkNSXs35Yg6arw=3D=3D?=
X-IronPort-Anti-Spam-Filtered: true
X-IronPort-Anti-Spam-Result: =?us-ascii?q?A0AoAAD320Nd/4oNJK1cChoBAQEBAQI?= =?us-ascii?q?BAQEBBwIBAQEBgVYCAQEBAQsBgUQpJwNtVSAECyoKhBSDRwOLKIJbiVWOAoF?= =?us-ascii?q?CgRADVAkBAQEMAQEYCwoCAQGEQAIXgj4jNwYOAQMBAQQBAQIBBm2FHgyFSgE?= =?us-ascii?q?BAQECAQEBEAsGEQwBASwLAQsEAgEIEQQBAQECAh8HAgICHwYLFQgIAgQOBQg?= =?us-ascii?q?TB4MBgWoDDg8BAgyiQwKBOIhgcYEygnoBAQWBMgGDUw0LghMJgQwoAYYTgVm?= =?us-ascii?q?BKoJJF4FAP4ERRoJMPoIaRwEBgSkNBSiDCTKCJowgCBkegiiHMpQlQAkCghq?= =?us-ascii?q?GXIlKhBKCLocphBGKOYxiCYIMhiKBeItngjcCBAIEBQIOAQEFgWYigVhwFTu?= =?us-ascii?q?CbAmCOTdvAQGCSYJkgjCFP3KBKYohgTABgSABAQ?=
X-IronPort-AV: E=Sophos;i="5.64,337,1559520000"; d="scan'208";a="597478105"
Received: from alln-core-5.cisco.com ([173.36.13.138]) by rcdn-iport-3.cisco.com with ESMTP/TLS/DHE-RSA-SEED-SHA; 02 Aug 2019 06:48:00 +0000
Received: from XCH-ALN-016.cisco.com (xch-aln-016.cisco.com [173.36.7.26]) by alln-core-5.cisco.com (8.15.2/8.15.2) with ESMTPS id x726lxFV030960 (version=TLSv1.2 cipher=AES256-SHA bits=256 verify=FAIL); Fri, 2 Aug 2019 06:48:00 GMT
Received: from xhs-rtp-003.cisco.com (64.101.210.230) by XCH-ALN-016.cisco.com (173.36.7.26) with Microsoft SMTP Server (TLS) id 15.0.1473.3; Fri, 2 Aug 2019 01:47:59 -0500
Received: from xhs-rtp-001.cisco.com (64.101.210.228) by xhs-rtp-003.cisco.com (64.101.210.230) with Microsoft SMTP Server (TLS) id 15.0.1473.3; Fri, 2 Aug 2019 02:47:58 -0400
Received: from NAM02-SN1-obe.outbound.protection.outlook.com (64.101.32.56) by xhs-rtp-001.cisco.com (64.101.210.228) with Microsoft SMTP Server (TLS) id 15.0.1473.3 via Frontend Transport; Fri, 2 Aug 2019 02:47:58 -0400
ARC-Seal: i=1; a=rsa-sha256; s=arcselector9901; d=microsoft.com; cv=none; b=Z/U6q14NnwKFEsqypjfX2qa/ouqQEaR0JtM1LGFaOQic6W9AoZg3WASq1/bj/sa2copgi7ZGWjyO5/5D364eEWZvYiD1vx8TcH5cRbr2nTTEqmdT2QkEMQ2gg22UrKA+DmlBj8jR8GZWJauwJjdZvINSlNREBIPxJAkTaitf+uBZUKZc7S5dUEP1MhnKbQWItJg4OJHlidIhPWLLwwRptIB2ZBzWYT9ex7qNWIH2M9is9S5yvT/6G+OE9jB9Z+79FRpsXUdE/08Ckh80isLroOPim0/VnXN4IgZqSug3XSWo7yQ8iUOaADB15mL04k6LRLl/SdxvKBBM5SlvJ15VSA==
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=dhwcdi5WrOW7tgcm4lQiUXLYu6Blb3DLSimFbyFvtNg=; b=gu1V9pwCUpiZmny/HkP6tt0uO7LvJXNQd9LUosQxhgh4U/t/HE7hlsTFYGu1vaHn6vk7bJiPyMAOwzL+vM+3de7iYfQn0nLG4k+f7V20J8vTzi7alPblOkwNLa609czNu0ADmkXwGlnqn9ZXWhjbMHtlaZiShPWt2idMFti2w9mezgIftoBn4diS4lJNHuAaBZp3qz5D1G5VKEoCeLRR6dQh92mCJpcn37beh3hjIIYQMeg36ktWN1UbFdAMPUHpvnGIBbjKE8j7GdXq7oRZBrVpmn+vHxdYqnpkgHqKl7BWcWqkUq4/7XKKWfxoM3qERfuzAw4LJ65gcpK2w3M99w==
ARC-Authentication-Results: i=1; mx.microsoft.com 1;spf=pass smtp.mailfrom=cisco.com;dmarc=pass action=none header.from=cisco.com;dkim=pass header.d=cisco.com;arc=none
DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=cisco.onmicrosoft.com; s=selector2-cisco-onmicrosoft-com; h=From:Date:Subject:Message-ID:Content-Type:MIME-Version:X-MS-Exchange-SenderADCheck; bh=dhwcdi5WrOW7tgcm4lQiUXLYu6Blb3DLSimFbyFvtNg=; b=Uw9LhnLJWXBmHwPbC0cT5IaVE3mnZ0PR2gQIw6eW0/ZAfRFfrTVbpatsbsCKgF/ONnGsoAC/u9YzSkPXzeKK7GujjkMF+KJqZF5qeuiuu7TttS/tHmx2cmuympqkAyUL45q6j+lRgXLYdT/vMRrcUiLdILGts3+o9s4zStVtkF8=
Received: from BYAPR11MB2584.namprd11.prod.outlook.com (52.135.227.17) by BYAPR11MB2727.namprd11.prod.outlook.com (52.135.227.157) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.20.2115.15; Fri, 2 Aug 2019 06:47:57 +0000
Received: from BYAPR11MB2584.namprd11.prod.outlook.com ([fe80::d443:d196:b8f6:d858]) by BYAPR11MB2584.namprd11.prod.outlook.com ([fe80::d443:d196:b8f6:d858%7]) with mapi id 15.20.2094.017; Fri, 2 Aug 2019 06:47:57 +0000
From: "Frank Brockners (fbrockne)" <fbrockne@cisco.com>
To: Tom Herbert <tom@quantonium.net>
CC: Greg Mirsky <gregimirsky@gmail.com>, IPPM Chairs <ippm-chairs@ietf.org>, IETF IPPM WG <ippm@ietf.org>
Thread-Topic: [ippm] Adoption call for draft-mizrahi-ippm-ioam-flags Re: Regarding draft-mizrahi-ippm-ioam-flags
Thread-Index: AQHVQxPfcyCqkf67BUCt2X7oyo6/OKblHFwAgAA/ZQCAASInQIAAMOeAgAADY5CAADg8gIAAiZcA
Date: Fri, 2 Aug 2019 06:47:56 +0000
Message-ID: <BYAPR11MB2584978168353AC7C0D1493EDAD90@BYAPR11MB2584.namprd11.prod.outlook.com>
References: <CA+RyBmVnkMFEQv=Hr3y9OD09+_vocHRgnGQnLwEVO=yuTcptEQ@mail.gmail.com> <EAB5C70D-A160-423E-84FE-3CE7AC079168@trammell.ch> <CA+RyBmWxh+FRxnrFH9ZbQ_F0V42UTm8aE0yOpd2N7vXb-Eqaiw@mail.gmail.com> <CAPDqMeoS8ZatMF9SXNYi0bPDdRN7T0gj-snxrLNL+1arGv5RTw@mail.gmail.com> <BYAPR11MB258458D075E929C9C0CF4901DADE0@BYAPR11MB2584.namprd11.prod.outlook.com> <CA+RyBmXzZvi7GBC6OJ_+RcRFp_xQMmfnGAwhxUdh9YQ-4fBw3A@mail.gmail.com> <BYAPR11MB2584A68317656AB94D1EE2C1DADE0@BYAPR11MB2584.namprd11.prod.outlook.com> <CAPDqMeox8Q0Oqn-zqDVTLbAcyzpCKo+8FVXctCmNKUgsHXcg3w@mail.gmail.com>
In-Reply-To: <CAPDqMeox8Q0Oqn-zqDVTLbAcyzpCKo+8FVXctCmNKUgsHXcg3w@mail.gmail.com>
Accept-Language: en-US
Content-Language: en-US
X-MS-Has-Attach:
X-MS-TNEF-Correlator:
authentication-results: spf=none (sender IP is ) smtp.mailfrom=fbrockne@cisco.com;
x-originating-ip: [173.38.220.53]
x-ms-publictraffictype: Email
x-ms-office365-filtering-correlation-id: d6a8b945-75f4-4f67-1eed-08d717155a3a
x-microsoft-antispam: BCL:0; PCL:0; RULEID:(2390118)(7020095)(4652040)(8989299)(5600148)(711020)(4605104)(1401327)(4534185)(4627221)(201703031133081)(201702281549075)(8990200)(2017052603328)(7193020); SRVR:BYAPR11MB2727;
x-ms-traffictypediagnostic: BYAPR11MB2727:
x-ms-exchange-purlcount: 3
x-microsoft-antispam-prvs: <BYAPR11MB2727831B4A0C4281060E9035DAD90@BYAPR11MB2727.namprd11.prod.outlook.com>
x-ms-oob-tlc-oobclassifiers: OLM:10000;
x-forefront-prvs: 011787B9DD
x-forefront-antispam-report: SFV:NSPM; SFS:(10009020)(4636009)(39860400002)(136003)(366004)(396003)(376002)(346002)(199004)(189003)(51444003)(54094003)(13464003)(51914003)(81166006)(6246003)(8676002)(8936002)(81156014)(2906002)(14454004)(76116006)(66556008)(64756008)(66446008)(66946007)(74316002)(7736002)(30864003)(4326008)(68736007)(66476007)(305945005)(486006)(66066001)(476003)(5660300002)(446003)(11346002)(52536014)(25786009)(102836004)(6116002)(71200400001)(3846002)(478600001)(966005)(561944003)(71190400001)(33656002)(14444005)(99286004)(256004)(86362001)(26005)(6506007)(7696005)(76176011)(6436002)(53546011)(186003)(9686003)(6916009)(54906003)(316002)(6306002)(53936002)(229853002)(55016002); DIR:OUT; SFP:1101; SCL:1; SRVR:BYAPR11MB2727; H:BYAPR11MB2584.namprd11.prod.outlook.com; FPR:; SPF:None; LANG:en; PTR:InfoNoRecords; A:1; MX:1;
received-spf: None (protection.outlook.com: cisco.com does not designate permitted sender hosts)
x-ms-exchange-senderadcheck: 1
x-microsoft-antispam-message-info: ZormRAj9VVbbtca4GLIeY/svrwT/cX4olKSl48Jigq1DHFcwFwwQmokYOR3l5CdOwDTuqmT2uiMTtSKd/sMUCXiQPfIW0WhhPhNUBZI5qFt7P11WsVt9MPHIHyZVx5Wqat0OenJdnjTv625oY/zjVt0ZcOs8xCWgDUNJO1eKZ8bzlPQWCbiWWrkh5i2wip8aMIYaSGbw0/9D2NuViQdVTmxsoAnBfEc3YZqOzoPT1tWibwMjP+hEYaw7oUCZvtfnQ/hUoeH4JsZ+lgrBLIaxYKY0mXhvOAmVuUE7d6z/2yZcMPRTJFUN/TXEDF/feKokPyWMz/PfRLuPCJd8hGwOhqIiUf1ASUvByJbchR6C889k5UrLjbOqOWq0Tdh4G0hPhckGveHNi8ZpG/m5QPjTssHGF/a38Ja3Oqfm5mCe5lU=
Content-Type: text/plain; charset="utf-8"
Content-Transfer-Encoding: base64
MIME-Version: 1.0
X-MS-Exchange-CrossTenant-Network-Message-Id: d6a8b945-75f4-4f67-1eed-08d717155a3a
X-MS-Exchange-CrossTenant-originalarrivaltime: 02 Aug 2019 06:47:56.9676 (UTC)
X-MS-Exchange-CrossTenant-fromentityheader: Hosted
X-MS-Exchange-CrossTenant-id: 5ae1af62-9505-4097-a69a-c1553ef7840e
X-MS-Exchange-CrossTenant-mailboxtype: HOSTED
X-MS-Exchange-CrossTenant-userprincipalname: fbrockne@cisco.com
X-MS-Exchange-Transport-CrossTenantHeadersStamped: BYAPR11MB2727
X-OriginatorOrg: cisco.com
X-Outbound-SMTP-Client: 173.36.7.26, xch-aln-016.cisco.com
X-Outbound-Node: alln-core-5.cisco.com
Archived-At: <https://mailarchive.ietf.org/arch/msg/ippm/pqQC5JjiBuIK1nkMh9IAYBg27RQ>
Subject: Re: [ippm] Adoption call for draft-mizrahi-ippm-ioam-flags Re: Regarding draft-mizrahi-ippm-ioam-flags
X-BeenThere: ippm@ietf.org
X-Mailman-Version: 2.1.29
Precedence: list
List-Id: IETF IP Performance Metrics Working Group <ippm.ietf.org>
List-Unsubscribe: <https://www.ietf.org/mailman/options/ippm>, <mailto:ippm-request@ietf.org?subject=unsubscribe>
List-Archive: <https://mailarchive.ietf.org/arch/browse/ippm/>
List-Post: <mailto:ippm@ietf.org>
List-Help: <mailto:ippm-request@ietf.org?subject=help>
List-Subscribe: <https://www.ietf.org/mailman/listinfo/ippm>, <mailto:ippm-request@ietf.org?subject=subscribe>
X-List-Received-Date: Fri, 02 Aug 2019 06:48:06 -0000


> -----Original Message-----
> From: Tom Herbert <tom@quantonium.net>
> Sent: Freitag, 2. August 2019 00:27
> To: Frank Brockners (fbrockne) <fbrockne@cisco.com>
> Cc: Greg Mirsky <gregimirsky@gmail.com>om>; IPPM Chairs <ippm-
> chairs@ietf.org>gt;; IETF IPPM WG <ippm@ietf.org>
> Subject: Re: [ippm] Adoption call for draft-mizrahi-ippm-ioam-flags Re:
> Regarding draft-mizrahi-ippm-ioam-flags
> 
> On Thu, Aug 1, 2019 at 12:12 PM Frank Brockners (fbrockne)
> <fbrockne@cisco.com> wrote:
> >
> > Hi Greg,
> >
> >
> >
> > Please see inline…
> >
> >
> >
> > From: Greg Mirsky <gregimirsky@gmail.com>
> > Sent: Donnerstag, 1. August 2019 20:54
> > To: Frank Brockners (fbrockne) <fbrockne@cisco.com>
> > Cc: Tom Herbert <tom@quantonium.net>et>; IPPM Chairs
> > <ippm-chairs@ietf.org>rg>; IETF IPPM WG <ippm@ietf.org>
> > Subject: Re: [ippm] Adoption call for draft-mizrahi-ippm-ioam-flags
> > Re: Regarding draft-mizrahi-ippm-ioam-flags
> >
> >
> >
> > Hi Frank,
> >
> > thank you for your expedient response and the clarification, much
> appreciated. I have some follow-up questions but your response, in my opinion,
> supports my original evaluation of the draft that it is not ready for WG adoption.
> I don't agree that the presumed benefits of the proposed Loopback flag
> outweigh risks that were called out during the meeting and were pointed by Tom
> and me.
> >
> > Also, thank you for informing everyone that a design team is forming to define
> the use of the Immediate flag. I think that that flag should be introduced along
> with the clear and firm specification of its utilization.
> >
> > And I'm still not clear about how the Active flag can be used. You suggest that
> it is intended as complementary to "an operator who uses his own probing".
> What such "own probing" could be? Why would the operator use well-known
> standard-based active OAM for fault management and performance
> monitoring?
> >
> >
> >
> > …FB: draft-lapukhov-dataplane-probe-01 is an example of an operator’s
> approach to probing. I’ve also seen deployments where the probing is integrated
> with the application – i.e. part of the application solution, which is another
> example domain where specific health checks are used.
> >
> >
> >
> > And, going back to the scenario in DC. I wonder why the well-known
> Traceroute is not sufficient?
> >
> >
> >
> > …FB: In the scenario discussed below, detection speed was the driving factor –
> the IOAM loopback solution gives you an indication of the failed link in less than
> 1 RTT.
> 
> Frank,
> 
> I'm doubtful it would be practical to set loopback on every packet given the
> amplification characteristic, which means that either it's done as a periodic
> probe or on demand when the application has reason to suspect a failing link. In
> either case, it seems like the latency to detect and identify a failing link would be
> greater than 1 RTT. Am I missing something?

Tom,

you would not set loopback on every packet. Let me re-explain the deployment scenario:

* Operator runs a custom application UDP probe - which makes probe traffic follow all paths the application uses.
* On detecting failure of a specific probe for a specific connection, IOAM tracing is turned on with loopback for *that* connection.
* Once IOAM tracing is turned on, you can detect the node/link where traffic is stuck within one RTT. I.e. identification can be done in 1 RTT, once you detected the failure.

So in other words, you only need the IOAM trace option with loopback added to a very small set of packets. In an ideal world even one packet would be sufficient.

Frank

> 
> Tom
> 
> >
> >
> >
> > Cheers, Frank
> >
> >
> >
> > Regards,
> >
> > Greg
> >
> >
> >
> > On Thu, Aug 1, 2019 at 12:32 PM Frank Brockners (fbrockne)
> <fbrockne@cisco.com> wrote:
> >
> >
> > Some additional notes on the different flags - restating and expanding the
> discussion we had at the WG meeting in Montreal:
> >
> > Loopback flag:
> > The loopback flag was inspired by a specific use case, which could be
> summarized as "rapid identification of a failed link/node in a DC": In a DC (read:
> controlled/specific domain), one runs UDP probes (draft-lapukhov-dataplane-
> probe-01) over a v6 fabric. In case a UDP probe detects a failure, one adds the
> IOAM trace option and enables loopback mode - i.e. every node sends a copy
> back to the source in addition to forwarding the packet. Correlating the
> information from both ends allows one to pinpoint the failed node/link rapidly
> and gives one a view of the overall forwarding topology. This use-case was
> implemented in FD.io/VPP roughly 2 years ago and was also showcased at IETF
> bits-n-bites. There is a rough outline of the open source implementation
> available here: https://jira.fd.io/browse/VPP-471 .
> > In more generic words: Loopback mode is like all IOAM, a domain specific
> feature. Loopback mode is to enrich an existing (here the dataplane-probe)
> active OAM mechanism.
> > Reading through the comments below, it proves that the current draft is
> indeed a good basis for the discussion and it also clearly shows that we need to
> add a section to the document that expands on how loopback mode is expected
> to be used.
> >
> > Immediate export flag:
> > Per the WG discussion in Montreal - and the follow up breakout meeting
> (https://mailarchive.ietf.org/arch/msg/ippm/Do9kJ9ED_grmTqwcZHSdpy3CmRk
> ):
> > The plan is to consolidate the IOAM-related content for a new "immediate
> export option" from draft-song-ippm-postcard-based-telemetry-04 and the
> description of the immediate export flag in draft-mizrahi-ippm-ioam-flags  into a
> new draft.
> >
> > Active flag:
> > The active flag is not to replace any existing active OAM mechanisms - but
> rather allow an operator who uses his own probing along with IOAM to flag a
> packet as a probe packet.
> >
> > Security considerations for flags in the context of PNF vs. VNF:
> > Thanks for raising the point. It would be great to see specifics/details
> discussed here on the list, so that those could be incorporated into the security
> section.
> >
> > Thanks, Frank
> >
> > > -----Original Message-----
> > > From: ippm <ippm-bounces@ietf.org> On Behalf Of Tom Herbert
> > > Sent: Donnerstag, 1. August 2019 00:41
> > > To: Greg Mirsky <gregimirsky@gmail.com>
> > > Cc: IPPM Chairs <ippm-chairs@ietf.org>rg>; IETF IPPM WG <ippm@ietf.org>
> > > Subject: Re: [ippm] Adoption call for draft-mizrahi-ippm-ioam-flags Re:
> > > Regarding draft-mizrahi-ippm-ioam-flags
> > >
> > > On Wed, Jul 31, 2019 at 11:53 AM Greg Mirsky <gregimirsky@gmail.com>
> > > wrote:
> > > >
> > > > Dear Authors,
> > > > thank you for bringing this proposal for the discussion. When
> > > > considering WG
> > > AP, I use the following criteria:
> > > >
> > > > is the document reasonably well-written; does it addresses a
> > > > practical problem; is the proposed solution viable?
> > > >
> > > > On the first point, I commend you - the draft is easy to read.
> > > > On the second point, I have several questions:
> > > >
> > > > What is the benefit of using Loopback flag in the Trace mode?
> > >
> > > This is unclear to me also. Additionally, I am concerned that
> > > protocol blindly reflects the packet back to the source without any
> > > regard to what else the packet contains. For instance, if a TCP
> > > packet is reflected by ten intermediate nodes this is nonsensical.
> > > The possibility of an amplification attack is obvious and in fact
> > > mentioned in the security section, however I'm skeptical that the proposed
> mitigation of rate limiting is sufficient.
> > >
> > > Minimally, it seems like the reflected packets should be wrapped in
> > > ICMP to mitigate spoofing attacks. Also, I wonder if traceroute
> > > methodology could be used for tracing, i.e. one sent packet results
> > > in at most one return packet (ICMP), to mitigate the amplification problem.
> > >
> > > Tom
> > >
> > > > Why is it important to limit the applicability of Loopback to only Trace
> mode?
> > > > What is the benefit of collecting the same, as I understand the
> > > > description,
> > > data on the return path to the source?
> > > > What is the benefit of using Active flag comparing to existing
> > > > active OAM
> > > protocols?
> > > > What is the benefit of using Immediate flag comparing to
> > > > Postcard-Based
> > > Telemetry (PBT) proposal?
> > > >
> > > > On the third point, I'd appreciate your clarification on these points:
> > > >
> > > > In which transports (I find that iOAM encapsulation has been
> > > > proposed for all
> > > known transports) you've envisioned to use Loopback flag?
> > > > The third bullet in Section 5 refers to a replica of the data
> > > > packet that follows
> > > the same path as the original packet. What controls that replication?
> > > > The last paragraph in the Security Consideration section relies on
> > > > "restricted
> > > administrative domain" to mitigate the threat of malicious attacks
> > > using a combination of iOAM extensions. That might be the case when
> > > operating in a PNF environment, but it is much more challenging to
> > > maintain such a trusted domain in VNF environment. How can these new
> > > security risks be mitigated in a VNF environment?
> > > >
> > > > Appreciate your consideration and clarifications to my questions.
> > > >
> > > > Regards,
> > > > Greg
> > > >
> > > > On Thu, Jul 25, 2019 at 2:07 PM Brian Trammell (IETF)
> > > > <ietf@trammell.ch>
> > > wrote:
> > > >>
> > > >> hi Greg,
> > > >>
> > > >> Thanks for the feedback; absolutely, we can do this the normal way.
> Authors:
> > > let's do a normal two-week adoption call for this document before
> > > publishing the update.
> > > >>
> > > >> This adoption call starts now.
> > > >>
> > > >> IPPM, please respond to this message with an indication to the
> > > >> mailing list of
> > > your support for adopting draft-mizrahi-ippm-ioam-flags as a working
> > > group document, in partial fulfillment of our charter milestone
> > > "submit a Standards Track draft on inband OAM based measurement
> methodologies to the IESG"
> > > (obviously, depending on how many documents we end up sending to the
> > > IESG, we may have to change the plurality of this milestone). If you
> > > do not support this, please send a message to the list explaining why.
> > > >>
> > > >> Thanks, cheers,
> > > >>
> > > >> Brian (as IPPM co-chair)
> > > >>
> > > >>
> > > >> > On 25 Jul 2019, at 13:15, Greg Mirsky <gregimirsky@gmail.com> wrote:
> > > >> >
> > > >> > Dear Chairs, et al.,
> > > >> > I appreciate that editors of draft-ietf-ippm-ioam-data followed
> > > >> > on the
> > > decision of the WG reached at the meeting in Prague to extract
> > > material not directly related to the definition of iOAM data
> > > elements from the document. The new draft was presented earlier this
> > > week and generated many comments. I feel that it would be right to
> > > discuss the draft and its relevance to the charter of the IPPM WG before
> starting WG adoption poll.
> > > >> >
> > > >> > Regards,
> > > >> > Greg
> > > >>
> > > > _______________________________________________
> > > > ippm mailing list
> > > > ippm@ietf.org
> > > > https://www.ietf.org/mailman/listinfo/ippm
> > >
> > > _______________________________________________
> > > ippm mailing list
> > > ippm@ietf.org
> > > https://www.ietf.org/mailman/listinfo/ippm