IETF - ROLL Interim Meeting 15:00 to 16:30 UTC - Tuesday 31th August 2021 Material https://datatracker.ietf.org/meeting/interim-2021-roll-02/session/roll https://github.com/roll-wg/ROLL-Interim-Meeting Meetecho: https://meetings.conf.meetecho.com/interim/?short=e89314d3-d762-4877-8f84-1108420ad8a4 Agenda Time (UTC) Duration Draft/Topic Presenter 15:00 - 15:05 5 min WG Status Ines/Dominique 15:05 - 15:35 30 min draft-ietf-roll-enrollment-priority Michael/Pascal 15:35 - 16:05 30 min draft-iwanicki-roll-rnfd Konrad 16:05 - 16:25 20 min draft-ietf-roll-dao-projection Pascal 16:25 - 16:30 5 min Open Floor Everyone Meeting notes [15:00] Meeting starts note well [15:02] WG Status storing-rootack: chairs will raise question again on the ML bier-ccast? Pascal: other priorities at the time. Carsten (re ietf-roll-ccast): had an implementation effort, no longer active. So status is waiting for implementation resources. nsa sitting in Alvaro's queue [15:11] draft-ietf-roll-enrollment-priority (Michael and Pascal) thought was done, then new issues raised. recently merged in the total DODAG size info (used to be a separate draft) issue: is min_priority change a change for Trickle? Pascal: first decide if nodes can change the min_priority as it goes down the DODAG. Now think should not change across teh DODAG. Does not affect 9032. Rahul: not change min_priority will simplify things, but intermediate should be able to say "don't join" if out of resources. Pascal: which resources? Rahul: Neighbor table, for example Pascal: this priority affects nodes not already part of the DAODAG. MCR: local node can take this min-priority and add local value MCR: no capacity for new node to join, node could increment the min_priority Pascal: first question: is min_priority incremented going the DODAG. We agree the answer is "incremented only locally", not propagated Konrad: only use case is disabling joining in a sub DODAG. Pascal: this value does not control the shape of the DODAG. Should not interact with routing. Pascal: sequencing argument is valid MCR: need an additional counter. If we have, can we increment down the DODAG Pascal: incremening down the DODAG is not what we want Pascal: think use case where node moves from one DODAG to another one, multiple PANS. You want to balance them. Decide which DODAG you want to join. Rahul: wanted to shut off new nodes joining this router, to balance the tree. Pascal: this use-case requires more than this priority. MCR: still dont know how to turn joining on and off, globally. Needs another lollipo counter. Interacts with Trickle if in DIO. Another distribution mechanism? Pascal: if constant, perfectly fine with Trickle. Konrad: if GLOBAL approach; also consistent with DODAG size. MCR: add lollipo counter. Will update the doc Rahul: Pascal: still need to define how the leaf augments the min_priority locally. Will discuss on ML. [15:42] draft-iwanicki-roll-rnfd (Konrad) describes use case in pratice, what exactly happens depends on implementation Increase control traffic due to root crash RNFD aims to minimize time and traffic, need additional option Design principle, goal to make it independent of RPL, so does not affect Protocol enormously Coordination of nodes to detect failure No wait to have a lot of traffic to detect crash => Proactive checking Pascal: Sentinels are one hop away from root ? they can talk together through the LBR, if it is up Description of the proposed solution: Sentinels, Acceptors, LORS, CFRC, RNFD Option, State machine, Pascal: "sufficeient" sentinel. How do they communicate if the root id down? Konrad: they don't. Merging of CFRC . If netwrok is sparse, (cross shape) ... Pascal: parameters have good threshold values that depend on topology. Suggest to consider to communicate through the root, and multicast to sentinels. Pascal: all first hops should declare that root is down, pretty much at the same time. Failure to receive this message in Trickle period would case them to ping the Root aggressively and declare it dead quickly. Will float the DODAGs. Pascal: recommend to think about the propoerties you want your protocol to acheive. Dominique: adoption? may need a charter adjustment. mcr: maintenance of RPL should be in our charter (from meetecho chat) Pascal: standards track or experimental? suggesting experimental. Think backward compatibility. Dominique: Confirm in ML [16:15] draft-ietf-roll-dao-projection (Pascal) thanks to Toerless for extensive review -20 in progress added the concept of Leg. Losse sequence of nodes between ingress and egress Policies to inject traffic out of scope Do not do detnet in the draft from Anand's review, clarify how to improve reliability of P-DAO injection could build real DODAG instead of just parallel legs. More complexity at ingress node, but more benefits. Exactly what RAW wants. could go into another draft. Pascal suggests to throw this into this draft before shipping. [16:40] Meeting adjourned