[6lo] Genart last call review of draft-ietf-6lo-multicast-registration-16

[Dan Romascanu via Datatracker <[e-mail]>]

Reviewer: Dan Romascanu
Review result: Ready with Issues

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Document: draft-ietf-6lo-multicast-registration-16
Reviewer: Dan Romascanu
Review Date: 2024-03-04
IETF LC End Date: 2024-03-05
IESG Telechat date: Not scheduled for a telechat

Summary:

This document updates the 6LoWPAN extensions to IPv6 Neighbor Discovery (RFC
4861, RFC 8505) to enable a listener to subscribe to an IPv6 anycast or
multicast address; the document updates RPL (RFC6550, RFC 6553) to add a new
Non-Storing Multicast Mode and a new support for anycast addresses in Storing
and Non-Storing Modes. This document extends RFC 9010 to enable the 6LR to
inject the anycast and multicast addresses in RPL.It also extends RFC 7400.

I am not an expert in this area. It took me quite an amount of time to deal in
the referenced, updated, extended and leveraged documents and I am sure I did
not grasp all the details. The specification is well written and solid, but I
have a major concern because of the large number of other specifications that
seem to be impacted. I would like to make sure that this complexity was taken
into account.

Major issues:

1. This specification updates 5 other RFCs, extends 2 RFCs and leverages
another 2 RFCs.This is quite unusual, and the updates are quite extensive. I am
concerned that for future implementers and operators, following the
specifications will also become difficult. Would not revising all or part of
the RFCs be a better way that would ease the implementations and deployments?

2. The deployment and backwards compatibility sections are quite good, but is
there a recommended strategy for updating existing deployments in the field?

Minor issues:

Nits/editorial comments: