IETF Logo Mail Archive

Re: [Spud] Connect and ACK Bits: Why?

Christian Huitema <huitema@microsoft.com> Mon, 13 July 2015 17:20 UTC

Return-Path: <huitema@microsoft.com>
X-Original-To: spud@ietfa.amsl.com
Delivered-To: spud@ietfa.amsl.com
Received: from localhost (ietfa.amsl.com [127.0.0.1]) by ietfa.amsl.com (Postfix) with ESMTP id 493A71B2C93 for <spud@ietfa.amsl.com>; Mon, 13 Jul 2015 10:20:15 -0700 (PDT)
X-Virus-Scanned: amavisd-new at amsl.com
X-Spam-Flag: NO
X-Spam-Score: -0.202
X-Spam-Level:
X-Spam-Status: No, score=-0.202 tagged_above=-999 required=5 tests=[BAYES_05=-0.5, MIME_8BIT_HEADER=0.3, RCVD_IN_DNSWL_NONE=-0.0001, SPF_HELO_PASS=-0.001, SPF_PASS=-0.001] autolearn=no
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 1l8isrMjqQ65 for <spud@ietfa.amsl.com>; Mon, 13 Jul 2015 10:20:14 -0700 (PDT)
Received: from na01-bl2-obe.outbound.protection.outlook.com (mail-bl2on0130.outbound.protection.outlook.com [65.55.169.130]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-SHA384 (256/256 bits)) (No client certificate requested) by ietfa.amsl.com (Postfix) with ESMTPS id 7A06C1B2C83 for <spud@ietf.org>; Mon, 13 Jul 2015 10:19:56 -0700 (PDT)
Received: from DM2PR0301MB0655.namprd03.prod.outlook.com (10.160.96.17) by DM2PR0301MB0654.namprd03.prod.outlook.com (10.160.96.16) with Microsoft SMTP Server (TLS) id 15.1.207.19; Mon, 13 Jul 2015 17:19:54 +0000
Received: from DM2PR0301MB0655.namprd03.prod.outlook.com ([10.160.96.17]) by DM2PR0301MB0655.namprd03.prod.outlook.com ([10.160.96.17]) with mapi id 15.01.0207.004; Mon, 13 Jul 2015 17:19:54 +0000
From: Christian Huitema <huitema@microsoft.com>
To: =?utf-8?B?TWlyamEgS8O8aGxld2luZA==?= <mirja.kuehlewind@tik.ee.ethz.ch>, Jacob Chappell <chappellind@gmail.com>
Thread-Topic: [Spud] Connect and ACK Bits: Why?
Thread-Index: AQHQuaQvpPywcQMRoEekZY+qlPvDhJ3ZVlMAgABUytA=
Date: Mon, 13 Jul 2015 17:19:54 +0000
Message-ID: <DM2PR0301MB06551595B03037418CD24D75A89C0@DM2PR0301MB0655.namprd03.prod.outlook.com>
References: <CANJ8QndAWK1ErRsUNAUHkA00aA5xzFsaQHiArCaN9jr64qCSnQ@mail.gmail.com> <FD304957-E34A-4CA5-B05A-3394D9062F1D@tik.ee.ethz.ch>
In-Reply-To: <FD304957-E34A-4CA5-B05A-3394D9062F1D@tik.ee.ethz.ch>
Accept-Language: en-US
Content-Language: en-US
X-MS-Has-Attach:
X-MS-TNEF-Correlator:
authentication-results: tik.ee.ethz.ch; dkim=none (message not signed) header.d=none;
x-originating-ip: [131.107.160.254]
x-microsoft-exchange-diagnostics: 1; DM2PR0301MB0654; 5:AtMYuPEn64VWf/oI8Ogu6WR83dLmjaf17tLVUlz1hsxNIHr9aFIK2xB3YT8oO3VbpD046N8iBHECro9lrvp5REQTIA7NMih/mRxC3oOV0rk/t+IZDSAwKPbICH+1Y2XV1E9pO9i26pemwQ08JxO5DQ==; 24:u5J4iAsJq5CQqr5KurLnN+Piri6pIiYCqyLfbahQsCyzRbF4gqik6dezh8K/w3q5bH3epysO7/WI4IRdrQJm29Ad/69NPfUrqgtPnFr0X1I=; 20:WuRJdrJuz4b4Up+h1w9OfIE+OHEVIHbHVQ6mqx4VGwYuBtPkQsIZnLvuHYR0ysRimP2cqW+Bd+WW6YTMQ09F7g==
x-microsoft-antispam: UriScan:;BCL:0;PCL:0;RULEID:;SRVR:DM2PR0301MB0654;
x-o365ent-eop-header: Message processed by - O365_ENT: Allow from ranges (Engineering ONLY)
x-microsoft-antispam-prvs: <DM2PR0301MB0654C08D5B33CF7202BB41C4A89C0@DM2PR0301MB0654.namprd03.prod.outlook.com>
x-exchange-antispam-report-test: UriScan:;
x-exchange-antispam-report-cfa-test: BCL:0; PCL:0; RULEID:(601004)(2401001)(5005006)(3002001); SRVR:DM2PR0301MB0654; BCL:0; PCL:0; RULEID:; SRVR:DM2PR0301MB0654;
x-forefront-prvs: 0636271852
x-forefront-antispam-report: SFV:NSPM; SFS:(10019020)(6009001)(24454002)(377454003)(13464003)(106116001)(86362001)(77096005)(50986999)(87936001)(54356999)(5003600100002)(2656002)(76176999)(122556002)(19580405001)(99286002)(40100003)(19580395003)(77156002)(62966003)(74316001)(76576001)(92566002)(5001960100002)(2950100001)(2900100001)(66066001)(46102003)(33656002)(86612001)(102836002)(5002640100001)(189998001); DIR:OUT; SFP:1102; SCL:1; SRVR:DM2PR0301MB0654; H:DM2PR0301MB0655.namprd03.prod.outlook.com; FPR:; SPF:None; MLV:sfv; LANG:en;
Content-Type: text/plain; charset="utf-8"
Content-Transfer-Encoding: base64
MIME-Version: 1.0
X-OriginatorOrg: microsoft.com
X-MS-Exchange-CrossTenant-originalarrivaltime: 13 Jul 2015 17:19:54.4659 (UTC)
X-MS-Exchange-CrossTenant-fromentityheader: Hosted
X-MS-Exchange-CrossTenant-id: 72f988bf-86f1-41af-91ab-2d7cd011db47
X-MS-Exchange-Transport-CrossTenantHeadersStamped: DM2PR0301MB0654
Archived-At: <http://mailarchive.ietf.org/arch/msg/spud/6fK8KEUOwA9htSis2z8mZr24zxs>
Cc: "spud@ietf.org" <spud@ietf.org>
Subject: Re: [Spud] Connect and ACK Bits: Why?
X-BeenThere: spud@ietf.org
X-Mailman-Version: 2.1.15
Precedence: list
List-Id: Session Protocol Underneath Datagrams <spud.ietf.org>
List-Unsubscribe: <https://www.ietf.org/mailman/options/spud>, <mailto:spud-request@ietf.org?subject=unsubscribe>
List-Archive: <https://mailarchive.ietf.org/arch/browse/spud/>
List-Post: <mailto:spud@ietf.org>
List-Help: <mailto:spud-request@ietf.org?subject=help>
List-Subscribe: <https://www.ietf.org/mailman/listinfo/spud>, <mailto:spud-request@ietf.org?subject=subscribe>
X-List-Received-Date: Mon, 13 Jul 2015 17:20:15 -0000


> -----Original Message-----
> From: Spud [mailto:spud-bounces@ietf.org] On Behalf Of 
> On Monday, July 13, 2015 5:10 AM, Mirja Kühlewind wrote:
> ...
> As described above it’s more about network state then client state. However,
> you probably will always need timers because you can never be sure that certain
> information will be delivered. However, if you can get more explicitly signals
> (and that’s why we also would like to have a SPUD finish/stop packet) you can
> assist network nodes as well as end host to e.g remove state quicker  and maybe
> also use SPUD to set timer values correctly (see the use case draft).

We have to account for possible route changes, without the endpoint being aware. That means that the first packet visible on the new path will not be the first packet end-to-end. This is a strong argument for NOT relying on an explicit "Start" flag. 

Then there is the flip side that any explicit signal STOP can be spoofed, which enables DOS attacks. On the other hand, "absence of traffic" cannot be easily spoofed.

-- Christian Huitema

v2.8.7 | Report a Bug | By Email