Hi Hendrik, The questions you ask are referrring to details of rfc8994 that where contributed by Pascal Thubert, and i am not deep enough into RPL details to answer, so Cc'ing ROLL WG to maybe get more insight. Michael Richardson might also know...
I do remember that i successfully tested changes in topology of a node (what you call mobility) in a pre-standard implementation, but i would know how to relate that to the RPL feature details you mention. Btw: If there is something coming out of the thread that you think shows some insufficiency, un-clarity or the like in rfc8994, i want to encourage you to open an issue on https://github.com/anima-wg/autonomic-control-plane so that it can be tracked better. Cheers Toerless On Tue, Sep 06, 2022 at 09:12:50PM +0200, Hendrik Mahrt wrote: > Hi, > > I've got some questions regarding the ACP RPL profile. I would be very > grateful if someone can help me with better understanding how it is supposed > to work in dynamic scenarios. > > First question: In the ACP RPL profile it is stated that "Nodes SHOULD > select more than one parent, at least three if possible". But I'm not sure > how multiple parents are selected by OF0 without nodes being greedy. The OF0 > RFC [RFC 6552] does not contain any information about multiple parents, > except for a 'backup feasible successor' (Section 4.2.2). But if I > understand correctly this successor is not 'actively' sought after, i.e., > the node does not actively increase its rank to obtain it, as that would > surely violate the rules of RPL on greediness formulated in RFC 6550 in > sections 3.7.1 and 8.2.2.4?! Or am I mistaken? > > Second question: The ACP RPL profile, as I understand it, features no form > of global repair or DODAG version increase (except manual intervention by > admin). How would that work with node mobility (which is mentioned in > Appendix A.4)? MaxRankIncrease would limit a node's rank movement within a > DODAG version and is only reset by a version increase, or not? I can also > imagine other scenarios besides mobility where the maximum rank increase > might lead to nodes not being able to select a parent in the long run, > without violating it. > > I also looked at the 'unstrung' RPL implementation for enlightenment but > found nothing really regarding multiple parents or handling link failures? > The implementation looks to be WIP though. I might also have missed > something, in which case I would be grateful if someone can point me to the > relevant code sections. > > > Thank you! > > Hendrik > -- --- [email protected] _______________________________________________ Anima mailing list [email protected] https://www.ietf.org/mailman/listinfo/anima
