6lo WG session - IETF 114, Philadelphia 17:30-18:30 (UTC) @ Philadelphia North 13:30-14:30 (local time) @ Philadelphia North Monday, July 25, 2022 Chairs: Shwetha Bhandari, Carles Gomez Responsible AD: Erik Kline Minute takers: Dominique Barthel Jabber scribe: TBD Agenda Introduction and draft status Bhandari/Gomez 10 min Agenda bashing; blue sheets; scribe; Jabber scribe Status update of 6lo Applicability & Use Cases Yong-Geun Hong 10 min https://datatracker.ietf.org/doc/html/draft-ietf-6lo-use-cases-13 IPv6 ND Multicast Address Listener Registration Pascal Thubert (&chairs) 10 min https://datatracker.ietf.org/doc/html/draft-ietf-6lo-multicast-registration-07 Transmission of SCHC-compressed Packets over IEEE 802.15.4 Carles Gomez 10 min https://datatracker.ietf.org/doc/html/draft-gomez-6lo-schc-15dot4-03 Native Short Address for LLN Expansion Luigi Iannone 5 min https://datatracker.ietf.org/doc/html/draft-li-6lo-native-short-address-03 Reliability Considerations of Native Short Addressing Luigi Iannone 15 min https://datatracker.ietf.org/doc/html/draft-li-nsa-reliability-00 Total: 60 min Meeting notes [13:30] Introduction and draft status (Bhandari/Gomez 10 min) Notetakers: Dominique Barthel, Ivan Martinez, Laurent Toutain Jabber/Zulip scribe: Use Meetecho, needed for automatic blue sheets and queue management Note well Agenda bashing: no comments. WG draft status 6lo-nfc draft stuck for 2 years? Issue about access to other SDO’s spec. Erik will deal with it 6lo use cases [13:40] Status update of 6lo Applicability & Use Cases (Yong-Geun Hong 10 min) https://datatracker.ietf.org/doc/html/draft-ietf-6lo-use-cases-13 https://datatracker.ietf.org/meeting/114/materials/slides-114-6lo-status-update-of-6lo-applicability-use-cases-00 YGH: Present the history and status of drafts Updates: 1. Comments from Robert Sparks, Added: Security considerations, Robert Sparks aggreed on the changes Appendix A describes deployement is used to help to design a network. YGH opinion is that it can be removed in a next version. 2. Comments from Peter Yee Carles: Regarding Apendix A introduction, Keep the appendix since there is some reference in the document Luigi/ I don't think we should remove it, we shall rather keep important information. Erik: could point to security consideration sections of other sub-IPv6 layers documents [13:50] IPv6 ND Multicast Address Listener Registration (Pascal Thubert (&chairs) 10 min) https://datatracker.ietf.org/doc/html/draft-ietf-6lo-multicast-registration-07 https://datatracker.ietf.org/meeting/114/materials/slides-114-6lo-draft-ietf-6lo-multicast-registration-pdf-00 PT: This work was developped at WiSUN alliance. Wanted to do equivalent of MLD, but as a push from the devices as opposed to pull from router PT: most RPL networks operate in non-storing, wanted to enable multicast in non-storing as well. PT: My question to Carles is / (following a comment by Carles ?): when a router reboots, how does it know that it needs to fetch some states? new router uptime option (will need 6man review): another hint for IoT device to realize router has rebooted. Carles: plan is launch coordinated WGLC coordinated between 6lo and ROLL, 6lo remaining the main home. Pascal: what about the uptime option at 6man? split it out of this draft? Tim Winters: multicast WG (MBONE?) could be interested too. Pascal: not multicast operation inside the graph, only replication at ingress of tunnel Tim: allright then Erik: intended use cases? Pascal: option used to presume that the router has lost its state. Erik: Can it be a document on its own to talk about this option? Pascal: pb of reference in the publication process? Erik: also generation number Pascal: recommendation to make it another, very short draft? Pascal: can keep separate. Was trying to avoid having yet another RFC. Erik: will take to the 6man chairs. Erik: we’ll discuss this offline. Pascal: could do the WGLC with current document, or take this option out. Chairs? Carles: after Erik has talk to 6man chairs, will implement change and launch WGLC. Erik: will start this email thread and let you know. [14:09] Transmission of SCHC-compressed Packets over IEEE 802.15.4 (Carles Gomez 10 min) https://datatracker.ietf.org/doc/html/draft-gomez-6lo-schc-15dot4-03 https://datatracker.ietf.org/meeting/114/materials/slides-114-6lo-schc-header-compression-over-ieee-802154-00 Carles: The motivation is that with SCHC we are able to achieve greater compression that the traditional way in 6lowpan and a theoretical lifetime improvement Carles: Presenting revision 03 doing the transmission of SCHC an 6lo network Carles: there was a problem on how to translate App/Dev into SCHC, instead of saying source and destination Carles: other scenarions in 802.15.4, where we can’t change Dev and App, so the consensus so far is to keep the terms. We refered to the architecture draft of LPWAN where we are having a solution that can be used here to avoid to store rules in intermediairy notes use RPL non storing mode. Pascal: you can use non storing mode in RPL even when the main DODAG is storing mode. The leaf only needs to know its own set of nodes, the root needs to know all sets of rules. SCHC compression will happen over the root-device tunnel. LT: Same comment as Pascal, if you use RPL you have UP and DW so is very very close Pascal: another possibility would be to have the first 6LR do the compression on behalf of the RUL (RPL Unaware Leaf). [14:20] Native Short Address for LLN Expansion (Luigi Iannone 5 min) https://datatracker.ietf.org/doc/html/draft-li-6lo-native-short-address-03 https://datatracker.ietf.org/meeting/114/materials/slides-114-6lo-native-short-address-for-lln-expansion-00 Luigi: Update on the NSA, added a clarification of checksum and some other minor changes Luigi: Pascal raised the issue of Reliability, we agreed is important, so we create a new Reliability Consideration section, with reference to the new relisability document (presented next). The document is stable, so we think we can go for WG adoption call. Carles: show of hands tool. 11 out of 20 respondants have read a version of the draft. adoption on the ML [14:27] Reliability Considerations of Native Short Addressing (Luigi Iannone 15 min) https://datatracker.ietf.org/doc/html/draft-li-nsa-reliability-00 https://datatracker.ietf.org/meeting/114/materials/slides-114-6lo-reliability-considerations-of-native-short-addressing-00 Luigi: New draft built in order the issue of reliability, there are several classes of solution multiple adresses per node, one for main topology, additional ones for redundant topologies. Node detecting link failure with main parent sends ICMPv6 message to root through seond topology so that root uses new path downwards. Pascal: this starts looking like a routing protocol, opening a Pandora box. Your first purpose was to avoid dealing with a routing protocol. Luigi: another solution is single address, but storing alternate parent, alternate children, in order to nbe able to recover from failure. Luigi: less state in nodes with multiple address situation. Adnan: LLN is not reliable in the first place. Can you provides numbers for your reliability? Carles: discussion to be continued on the maling list. [14:35] meeting adjourns