Hello folks, I'm not sure whether this is within scope as it regards LoWPANs ... please chastise freely and ignore if LoWPANs are out of scope. While trying to build a holistic view of LoWPANs, I'm consulting the IETF's informational and standards documents. I'm struck by the impression that, despite the significance of RFC6775's extension of Neighbor Discovery(ND) to low-power and lossy networks (LLNs), it is largely ignored by RFC6550 (RPL), with little to no reference to the ontological plane created in RFC6775's terminology section. For example: (a) router advertisements and router solicitations are substituted by DAG information objects (DIO) and DAG information solicitations (DIS) (b) the terms "mesh-under" and "route-over" (widely cited), defined in RFC6775, are absent from RFC6550 (c) jarringly: RFC6775 describes the route-over topologies as multi-IP-hop, while RFC6550 gathers DODAG nodes within the confines of the same IPv6 prefix as their border router - no multiple IP hops. Can anyone confirm or contradict this impression? Cheers, Etienne -- Ing. Etienne-Victor Depasquale Assistant Lecturer Department of Communications & Computer Engineering Faculty of Information & Communication Technology University of Malta Web. https://www.um.edu.mt/profile/etiennedepasquale