Minutes IETF110: lpwan
minutes-110-lpwan-00

# LPWAN WG IETF 110

Agenda and Meeting information
==============================

Meeting        :   IETF110 Wednesday, March 10, 2021
Venue          :   Online
Video Link     :  
https://meetings.conf.meetecho.com/ietf110/?group=lpwan&short=&item=1 Audo Link
     :   hhttp://mp3.conf.meetecho.com/ietf110/lpwan/1.m3u

Time           :   Session II - 15:30-16:30 CET (60min) (UTC+1)
Location       :   Room 4
Chairs         :   Pascal Thubert pthubert@cisco.com
                   Alexander Pelov a@ackl.io
Responsible AD :   Éric Vyncke
Minute takers  :   Laurent Toutain,

Live minutes   :   https://codimd.ietf.org/notes-ietf-110-lpwan
Live feeds     :   https://datatracker.ietf.org/meeting/agenda/

Other URLs     :   https://tools.ietf.org/wg/lpwan/
               :   https://datatracker.ietf.org/wg/lpwan/
               :   https://www.ietf.org/mailman/listinfo/lpwan

*    [15:30] Administrivia (chairs)                                          [
5min]
    o    Note-Well, Scribes, Agenda Bashing
    o    Status of drafts

*    [15:35] LPWAN Architecture and general newcomer presentation           
[15min]
    o    Associated drafts: draft-pelov-lpwan-architecture
    o    Presenter: Alexander Pelov

*    [15:50] Yang Data Model for SCHC                                       
[10min]
    o    Associated drafts: draft-ietf-lpwan-schc-yang-data-model
    o    Presenter: Laurent Toutain

*    [16:00] New ideas for SCHC-over-SigFox                                    
             [15min]
    o    Associated drafts: draft-ietf-lpwan-schc-over-sigfox
    o    Presenter: Juan Carlos Zuniga / Sergio Aguilar

*    [16:15] CoAP-over-SCHC                                                    
                 [ 5min]
    o    Associated drafts: draft-ietf-lpwan-coap-static-context-hc
    o    Presenter: Ana Minaburo

*    [16:20] SCHC-over-PPP                                                     
             [ 5min]
    o    Associated drafts: draft-thubert-intarea-schc-over-ppp
    o    Presenter: Pascal Thubert

*    [16:25] AOB, Adjourn                                                    [
5min]

## Minutes

Times in CET (UTC+1)

###    [15:30] Administrivia (chairs)                                         
[ 5min]
    o    Note-Well, Scribes, Agenda Bashing
    o    Status of drafts

Note Well, Agenda bashing (no comments on the agenda)
PT: WG status, a number of interims held
Update milestone, NBIOT in feb 2022, Sigfox in Oct 2021
SCHC-CoAP just entered RFC Ed queue, schc-over-lorawan already in RFC Editor
Queue yang review resquest to yang doctors

###    [15:35] LPWAN Architecture and general newcomer presentation           
[15min]
    o    Associated drafts: draft-pelov-lpwan-architecture
    o    Presenter: Alexander Pelov

AP: after major milestones achieved, a recap of LPWAN
RFC 8376: architecture, terminology...
This document: provide a reference architecture, decribes how nodes interact
document introduces SCHC Devive, SCHC Gateway and SCHC Peers
In SCHC device/Gw : Rule manager, rules and SCHC CD-FR
COREconf exchanges between Rule Manager
SCHC Peer to avoid some constrained implementation
Example of Network-level SCHC
Rule Mamager CORECONF/OSCORE exchanges can use SCHC CD-FR

###    [15:50] Yang Data Model for SCHC                                       
[10min]
    o    Associated drafts: draft-ietf-lpwan-schc-yang-data-model
    o    Presenter: Laurent Toutain

Most differences in the last update are clarifications in text, yang model
itself is stable Presents identifier definition logic, id types Structures:
optional field (question mark) Ready for WGLC PT: any feedback about YANG
doctors review? Éric: no news so far LT: no one has contacted us Alex: may need
more review, but WGLC is appropriate, if only to raise attention Pascal:
criteria are implementations exist, and "yang-ness" of document, happy to
launch LC

###    [15:58] New ideas for SCHC-over-SigFox                                  
           [15min]
    o    Associated drafts: draft-ietf-lpwan-schc-over-sigfox
    o    Presenter: Juan Carlos Zuniga / Sergio Aguilar

JCZ reports on hackathon work

Work on NoAck and AckOnErr

New co-authors: Sergio Aguilar, Diego Wistuba, Sandra Céspedes
Added examples
New proposal: compound ACK

Sergio presents the compound ACK slides
The focus is on ACK-on-Error.
Sigfox downlink payload is fixed size. Grouping ACKs would make sense to save
messages (when there are errors). Describes format of new compound-ACK message.

DB: do you mandate that padding bits are 0 in the Sigfox profiles?
SA: in 8724 the ACK format has padding bits of 0
DB: 8724 recommends (but does not mandate) that padding bits be 0. Wondering if
the Sigfox profile of SCHC is mandating that. Just make sure this is the case.
DB: are you using bitmap compression when using the aggregation? SA: since DL
payload fixed to 64 bits, we don't use it DB: sounds safer JCZ: the format
might be more complex LT: padding can comprise up to 7 bits, not more JCZ: we
are trying to comply with RFC 8724 to the extent possible, but we try to define
this in addition PT: if it suits your case, just do it DB: it is just a new
message format LT: do we generalize this to other protocols or is this only for
Sigfox? PT: it looks very opportunistic to the Sigfox case... I don't see we
need to define it elsewhere. We may leave it like that for now. AP: what if
other technologies are interested in having a similar mechanism? JCZ: from our
side we will try to document it for our use case PT: nice optimization for this
case. No need to spend time trying to generalize this now DB: recommend to make
it very explicit in the draft how an implementation can distinguish between a
regular ACK and a compound ACK JCZ: we wanted to first hear the feedback, and
now use the feedback and detailed description to include it in the next version
of the draft PT: would be nice to extend tutorial slides/material with the
compound ACK

##    [16:14] CoAP-over-SCHC                                                   
               [ 5min]
    o    Associated drafts: draft-ietf-lpwan-coap-static-context-hc
    o    Presenter: Ana Minaburo

Draft just entered RFC Ed queue.
updates from -17 to -19
significant rework on Security Considerations sections, material provided by
Ben K. also some rework on variable length CoAP header fields processing. Ask
for RFC number 9024 ("aligned" with RFC 8724 :))

###    [16:19] SCHC-over-PPP                                                   
                   [ 5min]
    o    Associated drafts: draft-thubert-intarea-schc-over-ppp
    o    Presenter: Pascal Thubert

Work taking place at Intarea WG, but help from LPWAN WG needed.
In PPP protocol, signal a new compression algortihm.

Compression would be symmetric (both ends would be "gateways")
Packet format presented

Padding is done between the SCHC header and payload (not at the end as stated
in RFC 8724) PT: is it legal within RFC8724?

This exercises the peerwise model of the architecture doc.

PT: any coauthors who want to work on this?
PT: do we want/need applicability statements in this document?
PT: anything else needs to be on the document?
PT: in Smart Building, Goose (?) protocol. Very chatty, long name strings.
Would love to SCHC-compress it. EV: highly recommends the LPWAN WG participants
to subscribe to interea mailing list (and comment) and to attend the intrea
session on Friday. Or even become co-authors

###    [16:31] Adjourn                                                    [
5min]