Return-Path: X-Original-To: 6tisch@ietfa.amsl.com Delivered-To: 6tisch@ietfa.amsl.com Received: from localhost (localhost [127.0.0.1]) by ietfa.amsl.com (Postfix) with ESMTP id 81079120073; Fri, 11 Oct 2019 06:40:55 -0700 (PDT) X-Virus-Scanned: amavisd-new at amsl.com X-Spam-Flag: NO X-Spam-Score: -1.998 X-Spam-Level: X-Spam-Status: No, score=-1.998 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, HTML_MESSAGE=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 RSdK17VLTi20; Fri, 11 Oct 2019 06:40:52 -0700 (PDT) Received: from mail-pl1-x636.google.com (mail-pl1-x636.google.com [IPv6:2607:f8b0:4864:20::636]) (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 D4004120090; Fri, 11 Oct 2019 06:40:52 -0700 (PDT) Received: by mail-pl1-x636.google.com with SMTP id j11so4504489plk.3; Fri, 11 Oct 2019 06:40:52 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=oKDu1RucBWbrGOUmfOFFk2gkk98R7PTdEjmeChCZ+P8=; b=kfkGJj07vioOWQIgiu0GJbM0lLzTIziCYmGOYAZ+V7vckXMie68BKU9Pytge/VEydx WDbM0zzGjjaO7AqBp0ZAzntlc7yhI17QNcjnw5Vb6IDtSQLTq5T3S4zTD1j8btCWvhFl wc7Q2ODCt3HgZj45c7fjmGL3d03YjUwRScuzRbc7/3vVDC4jxsQJeJktRouxAJRIjqH7 bpWHVTVzmF7mUe4QOsdLCnxvtMKME2WWQvzTEXmGwcVRc2LYbr2PYx8ev4IvcFFFEiBf XndK7rNyWJYY8I/aGnjmFOFoF/5mEoNzZqVcjF/6uELItCPgJ4r6oYBZ91KimqLRCl6B QU6w== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=oKDu1RucBWbrGOUmfOFFk2gkk98R7PTdEjmeChCZ+P8=; b=gVWXP2TzQ/idr2QXRsklec3OHoC8LeVQ88d+lZt4RVrfWneht7CMvVlf1irsoo+HXo 0hKD87ffRL43qHJ8P3JQcBtbNqcAeTfhYZqdNrOBG+XK99+q8wAKahWu++Zqq80pjQKo buuynXixZO+xCH+VqxdVQoSlwY5CRUClSvKwT3iMofQB3O5zpWDDl2Pb2sJZjVoPPr9I utZ/Bbx75zUqP8aXmcT4Lu8RU+6czxlb3Riwv4OSiwejkKQpxKJXicsmB73NhwB4+WR4 JvNXzQicNmYq/IkvUInLSTPUcYlLfshkxLJs7LRRw0lN+pFxjd3/nSkFnj7Rc7gRsWeP 7QLQ== X-Gm-Message-State: APjAAAXQp661Nr4ztZLxHkhYRESY0lvdx3iVCRmJp5+opb8LFGEaxDyl IAqG99oEfXVj0bdo4NamRMxtus+JF4rqIynlBzc= X-Google-Smtp-Source: APXvYqwOa0/f+0VUDZ2T/vRf02pYZHwjlQaV/ru/87ZpCLkvjm0mxKqvSZP7xqKMWg37IX5wZI7hINcThsMHCrHmgA8= X-Received: by 2002:a17:902:ac98:: with SMTP id h24mr15456142plr.128.1570801252076; Fri, 11 Oct 2019 06:40:52 -0700 (PDT) MIME-Version: 1.0 References: In-Reply-To: From: Tengfei Chang Date: Fri, 11 Oct 2019 15:40:41 +0200 Message-ID: To: Christian Hopfner Cc: "draft-ietf-6tisch-msf@ietf.org" , "6tisch@ietf.org" <6tisch@ietf.org> Content-Type: multipart/alternative; boundary="000000000000a48fce0594a2aa02" Archived-At: Subject: Re: [6tisch] Clarification on MSF-06 X-BeenThere: 6tisch@ietf.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: "Discuss link layer model for Deterministic IPv6 over the TSCH mode of IEEE 802.15.4e, and impacts on RPL and 6LoWPAN such as resource allocation" <6tisch.ietf.org> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Fri, 11 Oct 2019 13:40:56 -0000 --000000000000a48fce0594a2aa02 Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable Hi Christian, Thanks for pointing this issue out! The neighbor polling section is removed at 03 version. Can't remember why we removed it. I re-edited this sections to fit the current content of MSF draft. I paste it below. It will the be last step of boot behavior after it starts sending EB and DIO. The node SHOULD send some form of keep-alive messages to all its neighbors it has negotiated cell with. The Keep-Alive (KA) mechanism is detailed in [RFC7554 ]. It uses the keep-alive messages to its preferred parent to stay synchronized. It MAY use the keep- alive messages to other neighbors to have statistics on link quality. It MAY use the keep-alive messages to its children to ensure the child is still reachable. The RECOMMENDED period for sending keep- alive messages is KA_PERIOD. If the keep-alive message to a child fails at the link layer (i.e. the maximum number of link-layer retries is reached), the node SHOULD declare the child as unreachable. This can happen for example when the child node is switched off. When a neighbor is declared unreachable, the node MUST remove all negotiated cells with that neighbor from its own schedule. In addition, it MAY issue a 6P CLEAR to that neighbor (which can fail at the link-layer). The node MAY be removed from the neighbor table. If this is good for you, I will update the MSF to 07 with this change and propose WGLC right after. Thanks! Tengfei On Fri, Oct 11, 2019 at 1:09 PM Christian Hopfner < christian.hopfner@endress.com> wrote: > Hi authors, > > I may raise a clarification question before issuing WGLC for this draft. > > In the past there was a section in the draft dealing with neighbor pollin= g > which seems to me beeing an important topic in terms of schedule > consistency. > > In the latest version I don't see a mechanism which explains how a parent > keeps its schedule clean after some children silently disappeared (e.g.. > batteries are gone). As per my understanding in such a case the negotiate= d > RX cell towards the child remains in the schedule forever right? > > Previously this was handled by neighbor polling. Which required the paren= t > to send KA packets in a periodic manner to its childset. (This could be > identified by evaluation of the neighbor set where a negotiated RX cell w= as > scheduled to) > > What is the idea now how to deal with that issue? > > > Mit freundlichen Gr=C3=BC=C3=9Fen I Best regards > > Christian Hopfner > ------------------------------ > Developer | TPI F&E Plattform Informatik > Endress+Hauser SE+Co. KG | Hauptstrasse 1 | 79689 Maulburg | Germany > Phone: +49 7622 28 1883 > christian.hopfner@endress.com | www.pcm.endress.com > > ------------------------------ > > Endress+Hauser SE+Co. KG > Registergericht: Amtsgericht Freiburg i.Br. HRA 670225 > Sitz der Gesellschaft: Maulburg > Pers=C3=B6nlich haftender Gesellschafter: Endress+Hauser Administration S= E > Sitz des pers=C3=B6nlich haftenden Gesellschafters: Maulburg > Registergericht: Amtsgericht Freiburg i.Br. HRB 717326 > Vorstand: Dr. Peter Selders > Aufsichtsratsvorsitzender: Matthias Altendorf > ------------------------------ > > Gem=C3=A4ss der Datenschutzgrundverordnung (EU-DSGVO) sind wir verpflicht= et, > Sie zu informieren, > wenn wir personenbezogene Daten von Ihnen erheben. > > Dieser Informationspflicht kommen wir mit folgendem Datenschutzhinweis > nach. > ------------------------------ > > Endress+Hauser SE+Co. KG > Register Court: Local Court of Freiburg i.Br. HRA 670225 > Registered Office: Maulburg > General Partner: Endress+Hauser Administration SE > Registered Office of General Partner: Maulburg > Register Court: Local Court of Freiburg i.Br. HRB 717326 > Chief Executive Officer: Dr. Peter Selders > Chairman of the Board: Matthias Altendorf > ------------------------------ > > According to the General Data Protection Regulation, > we are obliged to inform you when collecting your personal data. > We comply with this information duty with the following Data Protection > Statement > > ------------------------------ > > > > Disclaimer: > > The information transmitted is intended only for the person or entity to > which it is addressed and may contain confidential, proprietary, and/or > privileged > material. Any review, retransmission, dissemination or other use of, or > taking of any action in reliance upon, this information by persons or > entities > other than the intended recipient is prohibited. If you receive this in > error, please contact the sender and delete the material from any compute= r. > This e-mail does not constitute a contract offer, a contract amendment, o= r > an acceptance of a contract offer unless explicitly and conspicuously > designated or stated as such. > > > _______________________________________________ > 6tisch mailing list > 6tisch@ietf.org > https://www.ietf.org/mailman/listinfo/6tisch > --=20 =E2=80=94=E2=80=94=E2=80=94=E2=80=94=E2=80=94=E2=80=94=E2=80=94=E2=80=94=E2= =80=94=E2=80=94=E2=80=94=E2=80=94=E2=80=94=E2=80=94=E2=80=94=E2=80=94=E2=80= =94=E2=80=94=E2=80=94=E2=80=94=E2=80=94=E2=80=94=E2=80=94=E2=80=94=E2=80=94= =E2=80=94=E2=80=94=E2=80=94=E2=80=94=E2=80=94=E2=80=94=E2=80=94=E2=80=94=E2= =80=94=E2=80=94=E2=80=94=E2=80=94=E2=80=94 Dr. Tengfei, Chang Postdoctoral Research Engineer, Inria www.tcahng.org =E2=80=94=E2=80=94=E2=80=94=E2=80=94=E2=80=94=E2=80=94=E2=80=94=E2=80=94=E2= =80=94=E2=80=94=E2=80=94=E2=80=94=E2=80=94=E2=80=94=E2=80=94=E2=80=94=E2=80= =94=E2=80=94=E2=80=94=E2=80=94=E2=80=94=E2=80=94=E2=80=94=E2=80=94=E2=80=94= =E2=80=94=E2=80=94=E2=80=94=E2=80=94=E2=80=94=E2=80=94=E2=80=94=E2=80=94=E2= =80=94=E2=80=94=E2=80=94=E2=80=94=E2=80=94 --000000000000a48fce0594a2aa02 Content-Type: text/html; charset="UTF-8" Content-Transfer-Encoding: quoted-printable
Hi Christian,

Thanks for pointing = this issue out!=C2=A0
The neighbor polling section is removed at = 03 version. Can't remember why we removed it.

= I re-edited this sections to fit the current content of MSF draft. I paste = it below. It will the be last step of boot behavior after it starts sending= EB and DIO.

 =
  The node SHOULD send some form of keep-alive messages to all its
   neighbors it has negotiated cell with.  The Keep-Alive (KA)
   mechanism is detailed in [RFC7554].  It =
uses the keep-alive messages
   to its preferred parent to stay synchronized.  It MAY use the keep-
   alive messages to other neighbors to have statistics on link quality.
   It MAY use the keep-alive messages to its children to ensure the
   child is still reachable.  The RECOMMENDED period for sending keep-
   alive messages is KA_PERIOD.


   If the keep-alive message t=
o a child fails at the link layer (i.e.
   the maximum number of link-layer retries is reached), the node SHOULD
   declare the child as unreachable.  This can happen for example when
   the child node is switched off.

   When a neighbor is declared unreachable, the node MUST remove all
   negotiated cells with that neighbor from its own schedule.  In
   addition, it MAY issue a 6P CLEAR to that neighbor (which can fail at
   the link-layer). The node MAY be removed from the neighbor table.

If this is=
 good for you, I will update the MSF to 07 with this change and propose WGL=
C right after.=C2=A0
Thanks!

Tengfei

On Fri, Oct 11, = 2019 at 1:09 PM Christian Hopfner <christian.hopfner@endress.com> wrote:
Hi authors,

I may raise a clarification question before issuing WGLC for this draft.

In the past there was a section in the draft dealing with neighbor polling = which seems to me beeing an important topic in terms of schedule consistenc= y.

In the latest version I don't see a mechanism which explains how a pare= nt keeps its schedule clean after some children silently disappeared (e.g..= batteries are gone). As per my understanding in such a case the negotiated= RX cell towards the child remains in the schedule forever right?

Previously this was handled by neighbor polling. Which required the parent = to send KA packets in a periodic manner to its childset. (This could be ide= ntified by evaluation of the neighbor set where a negotiated RX cell was sc= heduled to)

What is the idea now how to deal with that issue?

Mit freundlichen Gr=C3=BC=C3=9Fen I Best regards

Ch= ristian Hopfner

Devel= oper | TPI F&E Plattform Informatik
Endress+Hauser SE+Co. KG | Haupt= strasse 1 | 79689 Maulburg | Germany
Phone: +49 7622 28 1883
christian.hopfn= er@endress.com | www.pcm.endress.com

En= dress+Hauser SE+Co. KG
Registergericht: Amtsgericht Freiburg i.Br. HRA= 670225
Sitz der Gesellschaft: Maulburg
Pers=C3=B6nlich haftender= Gesellschafter: Endress+Hauser Administration SE
Sitz des pers=C3=B6n= lich haftenden Gesellschafters: Maulburg
Registergericht: Amtsgericht = Freiburg i.Br. HRB 717326
Vorstand:=C2=A0Dr. Peter Selders
<= span style=3D"font-family:arial,helvetica,sans-serif;font-size:10pt">Aufsic= htsratsvorsitzender: Matthias Altendorf

Ge= m=C3=A4ss der Datenschutzgrundverordnung (EU-DSGVO) sind wir verpflichtet, = Sie zu informieren,
wenn wir personenbezogene Daten von Ihnen erheben.=

Di= eser Informationspflicht kommen wir mit folgendem Datenschutzhinweis nach.

En= dress+Hauser SE+Co. KG
Register Court: Local Court of Freiburg i.Br. H= RA 670225
Registered Office: Maulburg
General Partner: Endress+Ha= user Administration SE
Registered Office of General Partner: Maulburg<= /span>
Register Court: Local Court of Freiburg i.Br. HRB 717326
Chief Executive Officer: Dr. Peter Selders
Chairman of the Boar= d: Matthias Altendorf

Ac= cording to the General Data Protection Regulation,
we are obliged to i= nform you when collecting your personal data.
We comply with this info= rmation duty with the following Data Protection Stat= ement

=C2=A0

Disclaimer= :

The information transmi= tted is intended only for the person or entity to which it is addressed and= may contain confidential, proprietary, and/or privileged
material. Any = review, retransmission, dissemination or other use of, or taking of any act= ion in reliance upon, this information by persons or entities
other than= the intended recipient is prohibited. If you receive this in error, please= contact the sender and delete the material from any computer.
This e-ma= il does not constitute a contract offer, a contract amendment, or an accept= ance of a contract offer unless explicitly and conspicuously designated or = stated as such.

=C2=A0

_______________________________________________
6tisch mailing list
6tisch@ietf.org https://www.ietf.org/mailman/listinfo/6tisch


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Dr. Tengfei, Chang
<= span style=3D"background-color:rgb(255,255,255)">Postdoctoral Research Engi= neer, Inria
=E2=80=94=E2=80=94=E2=80=94=E2=80=94=E2=80= =94=E2=80=94=E2=80=94=E2=80=94=E2=80=94=E2=80=94=E2=80=94=E2=80=94=E2=80=94= =E2=80=94=E2=80=94=E2=80=94=E2=80=94=E2=80=94=E2=80=94=E2=80=94=E2=80=94=E2= =80=94=E2=80=94=E2=80=94=E2=80=94=E2=80=94=E2=80=94=E2=80=94=E2=80=94=E2=80= =94=E2=80=94=E2=80=94=E2=80=94=E2=80=94=E2=80=94=E2=80=94=E2=80=94=E2=80=94=
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