IETF Logo Mail Archive

Re: [6lo] ND cache entries creation on first-hop routers

Brian E Carpenter <brian.e.carpenter@gmail.com> Wed, 03 July 2019 23:20 UTC

Return-Path: <brian.e.carpenter@gmail.com>
X-Original-To: 6lo@ietfa.amsl.com
Delivered-To: 6lo@ietfa.amsl.com
Received: from localhost (localhost [127.0.0.1]) by ietfa.amsl.com (Postfix) with ESMTP id D44A31200E0; Wed, 3 Jul 2019 16:20:08 -0700 (PDT)
X-Virus-Scanned: amavisd-new at amsl.com
X-Spam-Flag: NO
X-Spam-Score: -1.999
X-Spam-Level:
X-Spam-Status: No, score=-1.999 tagged_above=-999 required=5 tests=[BAYES_00=-1.9, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, FREEMAIL_FROM=0.001, RCVD_IN_DNSWL_NONE=-0.0001, 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=gmail.com
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 qNG8PFixmyga; Wed, 3 Jul 2019 16:20:06 -0700 (PDT)
Received: from mail-pf1-x42b.google.com (mail-pf1-x42b.google.com [IPv6:2607:f8b0:4864:20::42b]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by ietfa.amsl.com (Postfix) with ESMTPS id D5F15120096; Wed, 3 Jul 2019 16:20:06 -0700 (PDT)
Received: by mail-pf1-x42b.google.com with SMTP id p184so1985357pfp.7; Wed, 03 Jul 2019 16:20:06 -0700 (PDT)
DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=subject:to:cc:references:from:message-id:date:user-agent :mime-version:in-reply-to:content-language:content-transfer-encoding; bh=Y7lhN7XUTg96KVkoqRgi0UuIDrU0k0fofMnNYDIVOmA=; b=Oxn+uwDpLvO2SlgG0MR8y7cVdYY+KMnTAmoGaGjLrrHwXSP3yhmjOjD60KbVy3cF24 uxzF3kwvHBZ8LM60MhddefQk/xRVvdHLR62OHcS1mfsINAMQx+6VxsqygGly2c7X7ZTw lNiYosPWbw/AdysL+xTF/Jb0M9L2ihjINBbtac+kw5J3Tn9gOVIFYmPcW8pPKDqkK2Dl 156B7OAh/MqZlkcD+GmG+W94m6AKIw+mpaF4DL/8oqG6+Qo55GCPyLQ7HxWBwkynYq2O UKrRZlo5+MhDAzvnWGzy7cRov8jSkKTWVJ/nl4OVCPIqYfZRZJqzDmmDACKmZJoXoXNp T/KQ==
X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:subject:to:cc:references:from:message-id:date :user-agent:mime-version:in-reply-to:content-language :content-transfer-encoding; bh=Y7lhN7XUTg96KVkoqRgi0UuIDrU0k0fofMnNYDIVOmA=; b=gGmDNXTDTpR+YNXD7x9C+sERfcuMfHR3bmsA8GQ1GG9iFQu3A1uxkZNu/0Vo5T/c15 Eyq80vYxmswgxxXqdBouHPnzpOyh6krIwEvwnyNzGlvMjzgLmMO4ugmAks0wn2sW7JCo 09fyk+NZ3w9s0K09EMYgiMMI/q/Uy72wua6M1QGlJlEwQrMg4EwvFkQ8hhg0dx6Fp4Dk 76KcgfuEE1kPTAdHfraqvWBqkwf5OaFCk/IQ8eUlnu8Jaj6XyixU4JSawJ8thLxKjiBj CTRJ9hB6vtIbnDTtMBVWuOwBlylpszj5AVYrPHm1v+dexHTbn2S2mqk8hvP1Z+pExcrd Mb3w==
X-Gm-Message-State: APjAAAXC1u8Odh1w6qgiyfENhPUtqK6wrrkMuy1u0/RVCSg6aSg8Cwna DD+tqVJ4diZGLNCEjFhgwYzfVOVP
X-Google-Smtp-Source: APXvYqxH3kssX9n1hjUPFFlXZX2IRXl0wWnekzNySgGVudffLGXNyYPdGNaw5QrM2WxQXG+7akfh3Q==
X-Received: by 2002:a63:1a5c:: with SMTP id a28mr39663441pgm.418.1562196005832; Wed, 03 Jul 2019 16:20:05 -0700 (PDT)
Received: from [130.216.36.147] (sc-cs-567-laptop.uoa.auckland.ac.nz. [130.216.36.147]) by smtp.gmail.com with ESMTPSA id f17sm2883280pgv.16.2019.07.03.16.20.02 (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Wed, 03 Jul 2019 16:20:05 -0700 (PDT)
To: "Pascal Thubert (pthubert)" <pthubert@cisco.com>
Cc: Michael Richardson <mcr+ietf@sandelman.ca>, "6lo@ietf.org" <6lo@ietf.org>, Jen Linkova <furry13@gmail.com>, "6tisch@ietf.org" <6tisch@ietf.org>, V6 Ops List <v6ops@ietf.org>, 6man <6man@ietf.org>
References: <CAFU7BAQ4xrjNn9-EUyRhyHKDDT=f381Z4T6x6qJ=ftm2D2K4cw@mail.gmail.com> <5377.1562081856@localhost> <MN2PR11MB35652B81658AF0E9F718CD52D8FB0@MN2PR11MB3565.namprd11.prod.outlook.com> <0e80ea5d-d659-2d3e-43ac-674531f171eb@gmail.com> <BBB83984-C684-429A-86EA-3FD2DF20F519@cisco.com>
From: Brian E Carpenter <brian.e.carpenter@gmail.com>
Message-ID: <a9ddaf45-5f31-4d58-49c4-2594d9a8a436@gmail.com>
Date: Thu, 04 Jul 2019 11:20:00 +1200
User-Agent: Mozilla/5.0 (Windows NT 10.0; WOW64; rv:60.0) Gecko/20100101 Thunderbird/60.7.2
MIME-Version: 1.0
In-Reply-To: <BBB83984-C684-429A-86EA-3FD2DF20F519@cisco.com>
Content-Type: text/plain; charset="utf-8"
Content-Language: en-US
Content-Transfer-Encoding: quoted-printable
Archived-At: <https://mailarchive.ietf.org/arch/msg/6lo/DsWc9vvduSGjJ3AaQsQQ6I4bBj8>
Subject: Re: [6lo] ND cache entries creation on first-hop routers
X-BeenThere: 6lo@ietf.org
X-Mailman-Version: 2.1.29
Precedence: list
List-Id: "Mailing list for the 6lo WG for Internet Area issues in IPv6 over constrained node networks." <6lo.ietf.org>
List-Unsubscribe: <https://www.ietf.org/mailman/options/6lo>, <mailto:6lo-request@ietf.org?subject=unsubscribe>
List-Archive: <https://mailarchive.ietf.org/arch/browse/6lo/>
List-Post: <mailto:6lo@ietf.org>
List-Help: <mailto:6lo-request@ietf.org?subject=help>
List-Subscribe: <https://www.ietf.org/mailman/listinfo/6lo>, <mailto:6lo-request@ietf.org?subject=subscribe>
X-List-Received-Date: Wed, 03 Jul 2019 23:20:09 -0000

On 04-Jul-19 09:03, Pascal Thubert (pthubert) wrote:
> Sorry Brian I miss your point.
> 
> The discussion here is to find a way for the node to autoconf an address and then notice the router(s) proactively so the ND NCE is ready when the first packet comes from the outside for this node.
> 
> I agree wholeheartedly with Jen’s requirement.

Yes, I am not against satisfying this requirement, but we have a considerable legacy of stacks that don't do this - so until that legacy has vanished, the routers need to deal with it somehow.

> I agree less with the idea of overstretching ND as it stands to achieve this, for reasons I gave already. So prepopulate the NCE, yes, but do it right with protocol elements that guarantee a state that is accurate, secure, and persistent for a committed lifetime, not with yet another patch to the old structure.
> 
> I’m interested to have a parallel discussion on where RFC 8505 can not apply. In the products and use cases I’m aware of, it could, since we are actually faking it by snooping ND and DHCP to achieve similar but less accurate results.

So if you are advocating a generalisation of RFC8505 to non-6lo LANs, that's certainly a discussion we could have, IMHO.

Regards
    Brian

> 
> Take care,
> 
> Pascal
> 
>> Le 3 juil. 2019 à 22:39, Brian E Carpenter <brian.e.carpenter@gmail.com> a écrit :
>>
>> On 03-Jul-19 20:13, Pascal Thubert (pthubert) wrote:
>>
>> ...
>>> I'm baffled that the reactive ND is still the official technique for IPv6 lookup at 6MAN.
>>
>> How can it be otherwise when a node can give itself a new address at any time without notice?
>>
>> I'm not arguing with you about RFC 6775/8505 networks, but that doesn't apply everywhere.
>>
>>    Brian

v2.23.0 | Report a Bug | By Email