Re: [v6ops] draft-ietf-6man-grand : saving lookups

"Pascal Thubert (pthubert)" <pthubert@cisco.com> Sun, 09 August 2020 13:50 UTC

Return-Path: <pthubert@cisco.com>
X-Original-To: v6ops@ietfa.amsl.com
Delivered-To: v6ops@ietfa.amsl.com
Received: from localhost (localhost [127.0.0.1]) by ietfa.amsl.com (Postfix) with ESMTP id D2B643A0BFF; Sun, 9 Aug 2020 06:50:38 -0700 (PDT)
X-Virus-Scanned: amavisd-new at amsl.com
X-Spam-Flag: NO
X-Spam-Score: -9.597
X-Spam-Level:
X-Spam-Status: No, score=-9.597 tagged_above=-999 required=5 tests=[BAYES_00=-1.9, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, HTML_MESSAGE=0.001, RCVD_IN_MSPIKE_H3=0.001, RCVD_IN_MSPIKE_WL=0.001, SPF_PASS=-0.001, URIBL_BLOCKED=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=Pui6TX6r; dkim=pass (1024-bit key) header.d=cisco.onmicrosoft.com header.b=SmWchGrY
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 s-Bz_d3beEmW; Sun, 9 Aug 2020 06:50:36 -0700 (PDT)
Received: from rcdn-iport-5.cisco.com (rcdn-iport-5.cisco.com [173.37.86.76]) (using TLSv1.2 with cipher DHE-RSA-SEED-SHA (128/128 bits)) (No client certificate requested) by ietfa.amsl.com (Postfix) with ESMTPS id 4E6FC3A0BFE; Sun, 9 Aug 2020 06:50:36 -0700 (PDT)
DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=cisco.com; i=@cisco.com; l=9863; q=dns/txt; s=iport; t=1596981036; x=1598190636; h=from:to:cc:subject:date:message-id:references: in-reply-to:mime-version; bh=+mlDVO+7ZV+fmd3v5I7Cvmn2mcrrwUjWPKppVxisMvw=; b=Pui6TX6rK8DG5EJ+pqBZg9y+kcNjqaxY4YnbVouvmveSocJ7k03tVKD1 ENDs7gdneZU3xiWTuIBvUcfjB9Cv8wFhKY5Nvb6F2o/o56ZFefW1QHSsw YtF4MGQD/DrF7px5tJt1ZiHhh7KeILk4QKB9WqN9IoxmY6jPY3vN1WVIi 0=;
IronPort-PHdr: =?us-ascii?q?9a23=3Aw/Iw5R2t7EB04aWxsmDT+zVfbzU7u7jyIg8e44?= =?us-ascii?q?YmjLQLaKm44pD+JxWGuadiiVbIWcPQ7PcXw+bVsqW1X2sG7N7BtX0Za5VDWl?= =?us-ascii?q?cDjtlehA0vBsOJSCiZZP7nZiA3BoJOAVli+XzoPk1cGcK4bFrX8TW+6DcIEU?= =?us-ascii?q?D5Mgx4bu3+Bo/ViZGx0Oa/s53eaglFnnyze7R3eR63tg7W8MIRhNhv?=
X-IronPort-Anti-Spam-Filtered: true
X-IronPort-Anti-Spam-Result: =?us-ascii?q?A0DYCgC//i9f/5tdJa1gHQEBAQEJARI?= =?us-ascii?q?BBQUBggqBUlEHb1gvLIQ2g0YDjSsligeJcoRtglMDVQsBAQEMAQEYAQoKAgQ?= =?us-ascii?q?BAYRMAheCHwIkOBMCAwEBCwEBBQEBAQIBBgRthVwMhXIBAQQBARARHQEBLAs?= =?us-ascii?q?BDwIBCBgnAwICAh8GCxQRAgQOBSKDBAGBfk0DLgEOpykCgTmIYXaBMoMBAQE?= =?us-ascii?q?FhUYNC4IOAwaBOIJwg1+BAYU/GoFBP4E4DBCCTT6CGkIBAYE0WIJqM4Itj2S?= =?us-ascii?q?CXj2GYYtbkB9QCoJilRyEfQMeoBKMcJJfkhMCBAIEBQIOAQEFgWojRIETcBU?= =?us-ascii?q?7KgGCPlAXAg2OH4NxhRSFQnQ3AgYBBwEBAwl8kBUBAQ?=
X-IronPort-AV: E=Sophos;i="5.75,453,1589241600"; d="scan'208,217";a="539741096"
Received: from rcdn-core-4.cisco.com ([173.37.93.155]) by rcdn-iport-5.cisco.com with ESMTP/TLS/DHE-RSA-SEED-SHA; 09 Aug 2020 13:50:34 +0000
Received: from XCH-ALN-004.cisco.com (xch-aln-004.cisco.com [173.36.7.14]) by rcdn-core-4.cisco.com (8.15.2/8.15.2) with ESMTPS id 079DoYbc009564 (version=TLSv1.2 cipher=AES256-SHA bits=256 verify=FAIL); Sun, 9 Aug 2020 13:50:34 GMT
Received: from xhs-rtp-003.cisco.com (64.101.210.230) by XCH-ALN-004.cisco.com (173.36.7.14) with Microsoft SMTP Server (TLS) id 15.0.1497.2; Sun, 9 Aug 2020 08:50:34 -0500
Received: from xhs-aln-002.cisco.com (173.37.135.119) by xhs-rtp-003.cisco.com (64.101.210.230) with Microsoft SMTP Server (TLS) id 15.0.1497.2; Sun, 9 Aug 2020 09:50:33 -0400
Received: from NAM10-DM6-obe.outbound.protection.outlook.com (173.37.151.57) by xhs-aln-002.cisco.com (173.37.135.119) with Microsoft SMTP Server (TLS) id 15.0.1497.2 via Frontend Transport; Sun, 9 Aug 2020 08:50:33 -0500
ARC-Seal: i=1; a=rsa-sha256; s=arcselector9901; d=microsoft.com; cv=none; b=j87Uvzi6K2dkmb/PZaPFcDFR9uP2g5ifCMO2weiDxWSF8w9Md5DAachw58uwOO/qdVZMbYjqTB+XYPSghHrYUbObmWcb+6w0kuN4NGUYPGWOvzfyWHN/gHlM8zxbJERLOjdKjpuO1nNR4hmzpTttTD9IzANVeEblnJvQzCQgDpSINIPmQH179W5m6eQiXaovCToYonPiVMK6RWniP3aTMzxlMo5G/N40xiAc3yt6A/nNkeQd9SHEixGjYr+JfRs4hFrwVtbNan20y2TsRAkL/wZTMW3hxKA9NXVwIrlUgpWxkpjj+S6admwafOSe+WZEfGw/fN0V+Zl4DsncBtRoNA==
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=+mlDVO+7ZV+fmd3v5I7Cvmn2mcrrwUjWPKppVxisMvw=; b=MzKmD9T6n9P4ehot6hlkS70y4x9OcYJxkIExk6NO+EMRKHDm3tobYOcY4j1xpHwWMibEJrdt0RykyuVLVwKDFtBmQY+dFT3rJWRzWHUSxXpBZxrhZRL43Vy4/9stWjL3IOpi7xbM1p9kWr12lOimTzzN25zJqvIrnizpMG/2uhK0IdXIZKOOqlrG5+Z7WEYU1LHftVJ0YVKSEy0dzYtDNppbvuXtWr/woP5Heu3BITSyhdzgc70uiXtQbjKsREP4+m/6KxMkLmWgUW9d9uH4OvaSZvfL3fSKaKPloL8qOQYcrvA8rPnZgSvKJW2ZVic4t7NgnAyA35wSD5tvQcVdcg==
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=+mlDVO+7ZV+fmd3v5I7Cvmn2mcrrwUjWPKppVxisMvw=; b=SmWchGrYppyDBeVbpIo3e0eQtgaFlwlvuJdwxDpwSQv4+LqdXbCTHHCzZiCX3Qw23bc3hakk7NIAClScNo01ukW8H+liPexdIzCIRX0TDuz4TU/AYNh4YYo0+rWw9hrbhlVkqQEZiS/56O2DO+A9xJhdOxB1sis8x8xvGrZqgjo=
Received: from MN2PR11MB3565.namprd11.prod.outlook.com (2603:10b6:208:ea::31) by MN2PR11MB3808.namprd11.prod.outlook.com (2603:10b6:208:f8::27) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.20.3261.15; Sun, 9 Aug 2020 13:50:30 +0000
Received: from MN2PR11MB3565.namprd11.prod.outlook.com ([fe80::a53e:5801:92cc:3204]) by MN2PR11MB3565.namprd11.prod.outlook.com ([fe80::a53e:5801:92cc:3204%5]) with mapi id 15.20.3261.022; Sun, 9 Aug 2020 13:50:30 +0000
From: "Pascal Thubert (pthubert)" <pthubert@cisco.com>
To: Mark Smith <markzzzsmith@gmail.com>
CC: Jen Linkova <furry13@gmail.com>, 6man <ipv6@ietf.org>, IPv6 Operations <v6ops@ietf.org>, Jen Linkova <furry@google.com>
Thread-Topic: [v6ops] draft-ietf-6man-grand : saving lookups
Thread-Index: AQHWZ1aaeJpnUJSV20aes48tEhFRoKkr72qAgABfnoCAAcz6gIAABkFSgAFuC4CAAAMeAIAARf3o
Date: Sun, 9 Aug 2020 13:50:30 +0000
Message-ID: <6DD43215-8059-46F7-86A0-33722205B4F4@cisco.com>
References: <96fa6d80137241dd9b57fcd871c8a897@huawei.com> <CAFU7BARePzdeU5DFgoOWyrF0xZCj67_xkC2t8vMN2nH0d8aUig@mail.gmail.com> <37e2a7110f6b423eba0303811913f533@huawei.com> <CAKD1Yr1BJTAfp4PE+DY1yxeMm64kHetqBGYc5iaqZd3u0XrWpA@mail.gmail.com> <E176B084-24E1-434D-B15C-F364F64807BB@cisco.com> <CAFU7BASpHVTQ5SuNsdNu70ejZDnpVuPUaig+0_C=6q+mDQDFXA@mail.gmail.com> <BYAPR11MB355844AED3BA019B671797DDD8490@BYAPR11MB3558.namprd11.prod.outlook.com> <CAFU7BATuCN1rE=H9v0vv84UKKE7zD+LtRqh48Zf7hHN+sSGQJw@mail.gmail.com> <8B923F28-899B-4CE5-A3EB-B82E9E74A9B8@cisco.com> <CAFU7BATNnY3tYTc+woqypiu7VDtTghSsOnihGHw9bS0923Z+Vw@mail.gmail.com>, <CAO42Z2zE3qb=3e07se+XjhK+pT-btTJgZZbKbk7-01yCDfjkjQ@mail.gmail.com>
In-Reply-To: <CAO42Z2zE3qb=3e07se+XjhK+pT-btTJgZZbKbk7-01yCDfjkjQ@mail.gmail.com>
Accept-Language: fr-FR, en-US
Content-Language: fr-FR
X-MS-Has-Attach:
X-MS-TNEF-Correlator:
authentication-results: gmail.com; dkim=none (message not signed) header.d=none;gmail.com; dmarc=none action=none header.from=cisco.com;
x-originating-ip: [2a01:cb15:25e:cc00:f9de:28e0:1109:8c52]
x-ms-publictraffictype: Email
x-ms-office365-filtering-correlation-id: 02e521a1-85b3-4d7d-565c-08d83c6b2e0d
x-ms-traffictypediagnostic: MN2PR11MB3808:
x-microsoft-antispam-prvs: <MN2PR11MB3808C58EEB6B4A37C06AB341D8470@MN2PR11MB3808.namprd11.prod.outlook.com>
x-ms-oob-tlc-oobclassifiers: OLM:10000;
x-ms-exchange-senderadcheck: 1
x-microsoft-antispam: BCL:0;
x-microsoft-antispam-message-info: MEHyCXwSzuyfEiCB/AhUjs1XynSmTgoK30KzE9Z8wOjLshXheKrsRHejj/fczh+1eJmqr+c9bM0t2ZbvSiZJc8+OGJaWe7y8M/KOrfSdQy+NRRnfmpvMbKfjtsqGJA11dK7H+5kOZPRSc3l9hTNVDNHDd5IDrNojT63KzNbVLYNPAFXVjrd+fUq13zaXQirIarQcplNzKksJIy4b/scgfIPq2i7gk1ZWZHysTJEhX9LSVG6zfBsrV2Doz0iMuvqqro7bDuuilISBMdboP0bpeFNvt23HPrf03YwAX8TfNE77akrfTfX7pYxRhOoNLvWJm2Piy1YhRtH1eq4OjTTvUJnOUgkp0vDg4vBYROeIQaKbqaAl/2lUhkxa2opkhI36c+DNR8ZQi79qxAMxzWSFfYIWplyz1YY+tg4CXcAHPsmAwkxfHOsDMPZWW1RqUQNko0HYW84k6tP0qpnbfq61lQ==
x-forefront-antispam-report: CIP:255.255.255.255; CTRY:; LANG:en; SCL:1; SRV:; IPV:NLI; SFV:NSPM; H:MN2PR11MB3565.namprd11.prod.outlook.com; PTR:; CAT:NONE; SFTY:; SFS:(4636009)(366004)(346002)(39860400002)(376002)(396003)(136003)(166002)(86362001)(83380400001)(6512007)(2616005)(36756003)(8676002)(4326008)(316002)(71200400001)(2906002)(54906003)(5660300002)(33656002)(66476007)(66556008)(64756008)(66446008)(966005)(186003)(6486002)(8936002)(478600001)(53546011)(6916009)(6506007)(91956017)(76116006)(66946007)(66574015)(244885003); DIR:OUT; SFP:1101;
x-ms-exchange-antispam-messagedata: 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
x-ms-exchange-transport-forked: True
Content-Type: multipart/alternative; boundary="_000_6DD43215805946F786A033722205B4F4ciscocom_"
MIME-Version: 1.0
X-MS-Exchange-CrossTenant-AuthAs: Internal
X-MS-Exchange-CrossTenant-AuthSource: MN2PR11MB3565.namprd11.prod.outlook.com
X-MS-Exchange-CrossTenant-Network-Message-Id: 02e521a1-85b3-4d7d-565c-08d83c6b2e0d
X-MS-Exchange-CrossTenant-originalarrivaltime: 09 Aug 2020 13:50:30.2889 (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: bj5R+9WucYyMFBik7ipRiSGBu9USFpUR9/bsNrk5Edf2nU4cylzVCFixhkY/vhui/Ky+1C0dNpCbFfXrblD3ig==
X-MS-Exchange-Transport-CrossTenantHeadersStamped: MN2PR11MB3808
X-OriginatorOrg: cisco.com
X-Outbound-SMTP-Client: 173.36.7.14, xch-aln-004.cisco.com
X-Outbound-Node: rcdn-core-4.cisco.com
Archived-At: <https://mailarchive.ietf.org/arch/msg/v6ops/PW4sqSQhCeVyUA-NM_zAyoe08E4>
Subject: Re: [v6ops] draft-ietf-6man-grand : saving lookups
X-BeenThere: v6ops@ietf.org
X-Mailman-Version: 2.1.29
Precedence: list
List-Id: v6ops discussion list <v6ops.ietf.org>
List-Unsubscribe: <https://www.ietf.org/mailman/options/v6ops>, <mailto:v6ops-request@ietf.org?subject=unsubscribe>
List-Archive: <https://mailarchive.ietf.org/arch/browse/v6ops/>
List-Post: <mailto:v6ops@ietf.org>
List-Help: <mailto:v6ops-request@ietf.org?subject=help>
List-Subscribe: <https://www.ietf.org/mailman/listinfo/v6ops>, <mailto:v6ops-request@ietf.org?subject=subscribe>
X-List-Received-Date: Sun, 09 Aug 2020 13:50:39 -0000

We are facing 2 issues in the field that hurt especially in distributed fabrics with spanning L2 emulation (think eVPN and VxLAN)

One is with old privacy addresses that the host does not plan to use anymore. If the router NUDs them to check if they still exist, we create activity that gives a false sense of liveliness and renews the state indiscriminately with addresses that are really in use. A better NCE management could be achieved if we knew the intent of the host; but the current protocol does not expose that.

The second is with silent nodes like printers. Such a node has a fixed address but very rare connectivity. The printer may live a long time without any ND traffic and the network may forget the guy. The only way to find him is the multicast which as you know means broadcast.

If the host volunteers a periodic refresh of its active addresses at a period that the router can fathom then both issues can be avoided.

Ideally the period would depend on the usage to the address and the type of device. So it should also be suggested by the device.

Obviously we can do better than that but that’s a start...

Pascal

Le 9 août 2020 à 11:40, Mark Smith <markzzzsmith@gmail.com> a écrit :




On Sun, 9 Aug 2020, 19:29 Jen Linkova, <furry13@gmail.com<mailto:furry13@gmail.com>> wrote:
On Sat, Aug 8, 2020 at 9:38 PM Pascal Thubert (pthubert)
<pthubert@cisco.com<mailto:pthubert@cisco.com>> wrote:
> Maybe the host should renew the NCE in the router periodically ?

GRAND currently focuses on 'a new address being added to the
interface' scenario. It does not solve the case of a node starts using
an already configured address after a long period of inactivity.

I guess we can add to the very end of the Section 4.1.2 (the new text):
"A node MAY send unsolicited NAs for its preferred addresses
periodically to refresh the Neighbor Cache on the first hop routers."

On the other hand it might pollute the router NC with entries for
addresses which the node has configured but is not going to use.


Won't NUD probes keep those entries current in the routers' cache, even though hosts may not be actively using them?

I've thought that something like GRAND + NUD is starting to approach an address registration protocol, or at least, makes the routers' cache the "active addresses on a link" database.

Regards,
Mark.


What does the WG think?





--
SY, Jen Linkova aka Furry

--------------------------------------------------------------------
IETF IPv6 working group mailing list
ipv6@ietf.org<mailto:ipv6@ietf.org>
Administrative Requests: https://www.ietf.org/mailman/listinfo/ipv6
--------------------------------------------------------------------