Subject: [6tsch] minutes webex 20 September 2013

From: Thomas Watteyne <[email-masked]>
Date: Fri, 20 Sep 2013 14:01:53 -0700

All,

You will find the minutes of today's webex below.

FYI, all the minutes and slides are archived a
https://bitbucket.org/6tsch/meetings/.

Thanks to Xavi for taking notes!

As usual, fix anything we might have missed directly in the e-mail and
reply. We will approve and adopt the minutes at the beginning of the next
call.

Thomas

---

Minutes Webex 20 September 2013, 6TiSCH group

Note: timestamps in PDT.
Taking notes *(using Etherpad)*

   1. Xavi Vilajosana
   2. Thomas Watteyne

Present *(alphabetically)*

   1. Thomas Watteyne
   2. Pascal Thubert
   3. Alaeddine Weslati
   4. Geraldine Texier
   5. Guillaume Gaillard
   6. Ken Bannister
   7. Maria Rita Palattella
   8. Nicola Accettura
   9. Pouria Zand
   10. Qin Wang
   11. Raghuram Sudhaakar
   12. Tina Tsou
   13. Tom Phinney
   14. Xavi Vilajosana

Recording

   - Webex recording (audio+slides,streaming)
   -
   https://cisco.webex.com/ciscosales/lsr.php?AT=pb&amp;SP=MC&amp;rID=71580842&amp;rKey=c5bf8edd4d83ae2e<https://cisco.webex.com/ciscosales/lsr.php?AT=pb&SP=MC&rID=71580842&rKey=c5bf8edd4d83ae2e>
    *[62min]*

Slides

   - slides_130920_webex.ppt<https://bitbucket.org/6tsch/meetings/src/master/130920_webex/slides_130920_webex.ppt>:
   slides shared during the call

Agenda

   - Administrivia *[4min]*
      - Approval agenda
      - Approval minutes last call
      - WG news
   - Preparing for Vancouver *[10min]*
   - Updates to "minimal" draft *[10min]*
   - Need for hysteresis in using RPL OF0 *[15min]*
      - RFC6719
   - Scoping of Work Item 2 *[20min]*
      - Examples report traffic
      - Ideas for scope and discussion
   - AOB *[1min]*

Minutes

   - *[08.05]* Meeting starts
      - *[Thomas]* The group is at an interesting point. We have had many
      discussions. With 6 weeks left before Vancouver, good time to consolidate
      discussions in drafts.
   - *[08.05]* Administrivia *[4min]*
      - Approval agenda

      *Xavi* proposes to move his presentation on draft minimal at the end
      if time permits, or to next week. Change accepted.

      - Approval minutes last call

      No concerns raised on the call. Minutes approved.

      - WG news
         - Charting process in "External review" step. Scheduled for
         discussion by IESG on 09/26/2013 telechat.
         - Requested a 90min meeting slot during IETF 88 in Vancouver.
      - *[08.10]* Preparing for Vancouver *[10min]*
      - 6 weeks left to IETF 88
      - Main objective for Vancouver: have documents ready for WG adoption
         - Charter items: minimal, architecture, models
         - Others (TSCH, terminlogy)
         - Show activity on other drafts (security, 6top)
         - *[Pascal]* Volunteers for information and data models draft(s)?
         - *[Qin]* Difference between information and data model?
         - *[Pascal]* See http://tools.ietf.org/html/rfc3444. "Information
         model" is abstract description of interactinos, "data model" is very
         concrete (bits-and-bytes).

         *Raghuram* and *Pouria* volunteer. *Xavi* happy to help review,
         but not author. *Thomas* happy to help define problems statement
         and follow process, but not author.

         - *[Pascal]* Thanks. You will need to elect one editor.
      - Second objective for Vancouver: informal interop and mini-demo
         - Objectives
            - informal
            - show implementations related to 6TiSCH
            - discuss implementation details
            - at the very best, show some interop of different
            implementations of the minimal draft
         - We might need to ask for a room?
         - *[Thomas]* It would be good to document goals and methods in a
         "implementers guide" draft.

         *Xavi* volunteers to participate.

         - *[Pascal]* Interop or demo? We might want invite IAB members to
         come take a look.
         - *[Thomas]* This is very early on, so let's not announce it as an
         official interop.
      - Updates to "minimal" draft *[10min]*

   Pushed to end of call, or next week.

   - Need for hysteresis in using RPL OF0 *[15min]*
      - See http://tools.ietf.org/html/rfc6719
      - Requirement of pass a value boundary on rank in order to change
      parent (to avoid Hysteresis)
      - Experiment with other techniques:
         - stability counter.
         - delta threshold.
      - *[Xavi]* Should we add this to the minimal draft?
      - *[Pascal]* We could keep RFC6719 in minimal, use experiment to
      decide on hysteresis, and maybe push to ROLL in the future
      - *[Pascal]* Per the charter, at the end, our interest is to produce
      a recommendation
   - *[08.34]* Scoping of Work Item 2 *[20min]*
      - Intro *[Thomas]*
         - Thanks to volunteers to contribute to document
         - We need to scope work item 2 clearly. FYI, charter states:

         Produce an Information Model containing the management
         requirements of a 6TiSCH node. This includes describing how
an entity can
         manage the TSCH schedule on a 6TiSCH node, and query timeslot
information
         from that node. A data model mapping for an existing protocol (such as
         Concise Binary Object Representation (CBOR) over the Constrained
         Application Protocol (CoAP)) will be provided.

         - Start with presentationof example report flows by Pouria,
         followed by discussion
      - Examples report traffic *[Pouria]*
         - Pouria presents report traffic flow examples
         - ISA100.11a
            - Services to read/write/execute
            - interesting objects: candidates, neighbors, neighborDiag,
            channelDiag, alertPolicy
         - WirelessHART
            - metrics: device, neighbor, signal levels
         - Discussion/Questions
         - *[Xavi]* Do we want to focus our work in the same way as
         ISA/WirelessHART which is closed and restricted to a set of
parameters, or
         rather go to a more open mechanism.
         - *[Thomas]* +1. Our goal is not to replicate ISA/WirelessHART.
         Information Pouria presented is an example, we want to make sure the
         mechanism we design support this type of interaction. We're
looking for
         "outlier" type of interaction the CoAP-based solution we are designing
         might not cover.
         - *[Thomas]* Pouria, from this exercise, have you seen any type of
         interaction that CoAP might not be able to deal with?
         - *[Pouria]* A priori, it seems feasible to use CoAP. Although we
         need a more detailed investigation on CoAP.
         - *[Raghuram]* Extensibility is important, we need to come up with
         just the base of of commands and functionality we need, and allow for
         extensions.
         - *[Qin]* Clarifying question: Pouria's presentation did not touch
         on action and request flows. Do those not exist?
         - *[Pouria]* The application layer services include "execute",
         which can be mapped to the action flow we identified.
         - *[Thomas]* Let's not forget the decentralized case.
      - toward CoAP mapping *[Thomas]*
         - Important questions to answer for work item 2. CoAP related.
         These are just examples, but something like that could be
answered by work
         item 2 draft.
         - What is the URI scheme going to look like?
            - possible example: coap://6t/ to access 6TiSCH resource
         - How to map methods?
            - possible example: PUT coap://6t/c/ to add a cell
         - How to allow extensions?
            - possible example: use profiles. GET coap://6t/p/ to access
            list
         - *[09.07]* AOB *[1min]*

   *Qin* and *Maria Rita* volunteer to contribute to the information model
   as well.

   - *[09.08]* Meeting ends