Technical Summary
By and large, a correct operation of a RPL network requires border
routers to be up. In many applications, it is beneficial for the
nodes to detect a crash of a border router as soon as possible to
trigger fallback actions. This document describes RNFD, an extension
to RPL that expedites border router failure detection, even by an
order of magnitude, by having nodes collaboratively monitor the
status of a given border router. The extension introduces an
additional state at each node, a new type of RPL Control Message
Options for synchronizing this state among different nodes, and the
coordination algorithm itself.
Working Group Summary
The shepherd writeup notes "consensus was not rough". There is
an IOTDIR review which notes "not ready", however the author
responded in https://mailarchive.ietf.org/arch/msg/iot-directorate/M1AarDGI7qHpvDgz3zqiz2N1TRw/
and although the reviewer hasn't followed up to that reply,
it appears as though their concerns have been addressed.
Document Quality
There were several detailed reviews, including one by Victoria
Pritchard (https://mailarchive.ietf.org/arch/msg/rtg-dir/XXA90ID24LnIm8Rc2pKZFCmQQAA/)
which I (John) found especially helpful.
Personnel
The Document Shepherd for this document is Michael Richardson. The
Responsible Area Director is John Scudder.