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 1BA96120103; Fri, 11 Oct 2019 08:06:37 -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 Qu4N2WQDOACf; Fri, 11 Oct 2019 08:06:34 -0700 (PDT) Received: from mail-ot1-x329.google.com (mail-ot1-x329.google.com [IPv6:2607:f8b0:4864:20::329]) (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 2FAD51201CE; Fri, 11 Oct 2019 08:06:34 -0700 (PDT) Received: by mail-ot1-x329.google.com with SMTP id s22so8219600otr.6; Fri, 11 Oct 2019 08:06:34 -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=dgyYUlxk44bRp3gIYBw+4CFGyOLny+Gf5ml9gsMYafk=; b=GHbwI1jopgrm35qS+2uLynGmZS7tTT0cCfwM3B7T/xEqE8CWFnMrtDPJ2KkuLdnGO6 TPudkbDFq1/GIMYZkzUeVb8LYbksjHaYfDOQnIT/AkVvJCLz6ZtyO9TKqIVJx5XY8tVo RbxBVMAql30Pp1ARRmtlfXWdyBiwqG5Zs8D5hFq+OvKtVnWwTi+9YZPSTcfwYOxBxzDE fMtGsWbJIE5h8bt1GtycLaKTJqXr/+y39/EkrZs5VHBRvinHnenjb0Q7jOnyXEQoS3AZ E73x/WhOF5slOpSeLnpbZn8g3DrAH63T1GS8TjrR4WGGtok3Bqf5vU2nQ1T4NggvG9u6 fvpw== 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=dgyYUlxk44bRp3gIYBw+4CFGyOLny+Gf5ml9gsMYafk=; b=geoa2wMAHSWbMxrud7gQXPRzuahPkH0bEi3z2jAB4yzLjTdYCpAWHhSyW3smDHXQwV bTI591LiNEQzRnHjqiUWXkXfCdtNsvWApwSDE6h3fgKDkLFHvTT1CJt6xqQTZsI/MCoo v+yb4YhYkPDbatvVmjLka79WzSxta6uG4VkkRGR2P3irvNnuFhOTMvT9tx2fx6MTHSm4 2JTgRypk+154Lm7G+KszXMKX8HtQVmlFTEHCOFHYkrWSvWzNncWfsVPoJNczOC4XKRKr rD8equrza/+qalcVV/bxF3r8O/Dh87mNaUk3g2V488gYMatZ+A4m3AsqAnRpfbpcCT0B 5rLw== X-Gm-Message-State: APjAAAVazlX3YnrQB7BXoSi+QVN2r58cD+WQQv7zfK8giHXNitFvBrzN FhOaqQO/iUZpXztFibYq+HIqvbkn7D+Ptavekyk= X-Google-Smtp-Source: APXvYqyU8fd9nnFcL2vccTmR0pe43s1hxHnc/t64FawdioWAegAe7vl3kcFGKff8wPHXel9D3sZWZl+bEBvp9dlqHm4= X-Received: by 2002:a05:6830:1188:: with SMTP id u8mr9284384otq.190.1570806393418; Fri, 11 Oct 2019 08:06:33 -0700 (PDT) MIME-Version: 1.0 References: In-Reply-To: From: Abdussalam Baryun Date: Fri, 11 Oct 2019 17:06:04 +0200 Message-ID: To: Tengfei Chang Cc: Christian Hopfner , "draft-ietf-6tisch-msf@ietf.org" , "6tisch@ietf.org" <6tisch@ietf.org> Content-Type: multipart/alternative; boundary="0000000000001739730594a3ddd4" 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 15:06:48 -0000 --0000000000001739730594a3ddd4 Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable Hi Tengfei, I am interested like Christian to see the poll mechanism into this draft. I don't think it is right to refer to RFC7554 (problem statement) which is an informational RFC, while this draft is a proposed standard, I think it is better to state the mechanism into the use case of minimum scheduling. Furthermore, the RFC7554 does not mention once Keep-Alive message, but mentions signalling messages, which may confuse users. Best regards AB On Fri, Oct 11, 2019 at 3:41 PM Tengfei Chang wrote: > 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 past= e > it below. It will the be last step of boot behavior after it starts sendi= ng > 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 >> polling 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 paren= t >> keeps its schedule clean after some children silently disappeared (e.g.. >> batteries are gone). As per my understanding in such a case the negotiat= ed >> 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 co= uld >> be identified by evaluation of the neighbor set where a negotiated RX ce= ll >> was 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 = SE >> 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 verpflich= tet, >> 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 comput= er. >> This e-mail does not constitute a contract offer, a contract amendment, >> or 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 >> > > > -- > =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 > _______________________________________________ > 6tisch mailing list > 6tisch@ietf.org > https://www.ietf.org/mailman/listinfo/6tisch > --0000000000001739730594a3ddd4 Content-Type: text/html; charset="UTF-8" Content-Transfer-Encoding: quoted-printable
Hi Tengfei,

I am interested = like Christian to see the poll mechanism into this draft. I don't think= it is right to refer to RFC7554 (problem statement) which is an informatio= nal RFC, while this draft is a proposed standard, I think it is better to s= tate the mechanism into the use case of minimum scheduling. Furthermore, th= e RFC7554 does not mention once Keep-Alive message,=C2=A0but mentions signa= lling messages, which may confuse users.

Best rega= rds
AB

On Fri, Oct 11, 2019 at 3:41 PM Tengfei Chang &= lt;tengfei.chang@gmail.com&g= t; wrote:
Hi Christian,

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

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

   The node SHOULD send some form of keep-alive messages to all it=
s
   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 t=
he 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 upda=
te the MSF to 07 with this change and propose WGLC 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

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


--
=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

=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
<= /div>
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