Re: [Roll] useofrplinfo version 5

Michael Richardson <mcr+ietf@sandelman.ca> Mon, 18 July 2016 15:00 UTC

Return-Path: <mcr+ietf@sandelman.ca>
X-Original-To: roll@ietfa.amsl.com
Delivered-To: roll@ietfa.amsl.com
Received: from localhost (localhost [127.0.0.1]) by ietfa.amsl.com (Postfix) with ESMTP id 292B512DA99 for <roll@ietfa.amsl.com>; Mon, 18 Jul 2016 08:00:03 -0700 (PDT)
X-Virus-Scanned: amavisd-new at amsl.com
X-Spam-Flag: NO
X-Spam-Score: -3.188
X-Spam-Level:
X-Spam-Status: No, score=-3.188 tagged_above=-999 required=5 tests=[BAYES_00=-1.9, RP_MATCHES_RCVD=-1.287, SPF_PASS=-0.001] autolearn=ham autolearn_force=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 nSJ0a5UNRPBK for <roll@ietfa.amsl.com>; Mon, 18 Jul 2016 08:00:00 -0700 (PDT)
Received: from tuna.sandelman.ca (tuna.sandelman.ca [IPv6:2607:f0b0:f:3:216:3eff:fe7c:d1f3]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by ietfa.amsl.com (Postfix) with ESMTPS id D597A12DB07 for <roll@ietf.org>; Mon, 18 Jul 2016 07:32:20 -0700 (PDT)
Received: from sandelman.ca (obiwan.sandelman.ca [IPv6:2607:f0b0:f:2::247]) by tuna.sandelman.ca (Postfix) with ESMTP id A06DA200A7 for <roll@ietf.org>; Mon, 18 Jul 2016 10:41:44 -0400 (EDT)
Received: from obiwan.sandelman.ca (localhost [IPv6:::1]) by sandelman.ca (Postfix) with ESMTP id 0F02D638D1 for <roll@ietf.org>; Mon, 18 Jul 2016 10:32:20 -0400 (EDT)
From: Michael Richardson <mcr+ietf@sandelman.ca>
To: Routing Over Low power and Lossy networks <roll@ietf.org>
In-Reply-To: <8bd985a5-ded0-b5f3-8750-e0fb24c852ef@gmail.com>
References: <b9e569f12a008245ef824e340f510dff@xs4all.nl> <8bd985a5-ded0-b5f3-8750-e0fb24c852ef@gmail.com>
X-Mailer: MH-E 8.6; nmh 1.6+dev; GNU Emacs 24.5.1
X-Face: $\n1pF)h^`}$H>Hk{L"x@)JS7<%Az}5RyS@k9X%29-lHB$Ti.V>2bi.~ehC0; <'$9xN5Ub# z!G,p`nR&p7Fz@^UXIn156S8.~^@MJ*mMsD7=QFeq%AL4m<nPbLgmtKK-5dC@#:k
MIME-Version: 1.0
Content-Type: multipart/signed; boundary="=-=-="; micalg="pgp-sha1"; protocol="application/pgp-signature"
Date: Mon, 18 Jul 2016 10:32:20 -0400
Message-ID: <29661.1468852340@obiwan.sandelman.ca>
Archived-At: <https://mailarchive.ietf.org/arch/msg/roll/625wbhI6cLvI6UoC5b9W1MqmxGQ>
Subject: Re: [Roll] useofrplinfo version 5
X-BeenThere: roll@ietf.org
X-Mailman-Version: 2.1.17
Precedence: list
Reply-To: Routing Over Low power and Lossy networks <roll@ietf.org>
List-Id: Routing Over Low power and Lossy networks <roll.ietf.org>
List-Unsubscribe: <https://www.ietf.org/mailman/options/roll>, <mailto:roll-request@ietf.org?subject=unsubscribe>
List-Archive: <https://mailarchive.ietf.org/arch/browse/roll/>
List-Post: <mailto:roll@ietf.org>
List-Help: <mailto:roll-request@ietf.org?subject=help>
List-Subscribe: <https://www.ietf.org/mailman/listinfo/roll>, <mailto:roll-request@ietf.org?subject=subscribe>
X-List-Received-Date: Mon, 18 Jul 2016 15:00:03 -0000

Cenk Gündogan <cnkgndgn@gmail.com> wrote:
    >> Other question: how does the last 6LR know that the next node is a
    >> not_Raf?

    > I would try to answer this question in the following way:

    > I expect routes that were found _not_ with RPL, but e.g. configured
    > manually or through any other mechanism to be marked somehow
    > differently than routes that were accumulated with DAOs.  How to mark
    > routes "differently" seems to be implementation specific.  (but this
    > information would be used to fill in the `E` flag of Transit Options in
    > DAOs later).

yes, one would expect the neighbour cache to have a direct (connected) route
to a non-RPL aware node that was discovered through neighbour
discovery. (NS/NA).

    > So, if a rpl router forwards a packet downwards (storing-mode), it
    > somehow needs to know whether the (dst;next-hop) pair in a forwarding
    > table is rpl-born or not. If it is not rpl-born, then the IPIP header
    > containing the RPI must be removed before continuing the forwarding
    > process, otherwise the IPIP+RPI is re-added and targeted to the
    > next-hop.

    > You probably noticed that I used many "somehows" and generalized a lot
    > in the text above, but this process looks very blurry to me.  Any RPL
    > veterans available to make things clearer?

Actually, that's the point of this document: it's blurry for many!

--
Michael Richardson <mcr+IETF@sandelman.ca>, Sandelman Software Works
 -= IPv6 IoT consulting =-