Last Call Review of draft-ietf-v6ops-cpe-slaac-renum-04
review-ietf-v6ops-cpe-slaac-renum-04-genart-lc-resnick-2020-09-09-00

Request Review of draft-ietf-v6ops-cpe-slaac-renum
Requested rev. no specific revision (document currently at 05)
Type Last Call Review
Team General Area Review Team (Gen-ART) (genart)
Deadline 2020-09-09
Requested 2020-08-26
Authors Fernando Gont, Jan Zorz, Richard Patterson, Bernie Volz
Draft last updated 2020-09-09
Completed reviews Secdir Last Call review of -04 by Christopher Wood (diff)
Genart Last Call review of -04 by Pete Resnick (diff)
Iotdir Telechat review of -05 by Suresh Krishnan
Intdir Telechat review of -05 by Sheng Jiang
Assignment Reviewer Pete Resnick 
State Completed
Review review-ietf-v6ops-cpe-slaac-renum-04-genart-lc-resnick-2020-09-09
Posted at https://mailarchive.ietf.org/arch/msg/gen-art/0xWcEntdSUlftQx59wLj_sGQMeM
Reviewed rev. 04 (document currently at 05)
Review result Ready with Issues
Review completed: 2020-09-09

Review
review-ietf-v6ops-cpe-slaac-renum-04-genart-lc-resnick-2020-09-09

I am the assigned Gen-ART reviewer for this draft. The General Area
Review Team (Gen-ART) reviews all IETF documents being processed
by the IESG for the IETF Chair.  Please treat these comments just
like any other last call comments.

For more information, please see the FAQ at

<https://trac.ietf.org/trac/gen/wiki/GenArtfaq>.

Document: draft-ietf-v6ops-cpe-slaac-renum-04
Reviewer: Pete Resnick
Review Date: 2020-09-09
IETF LC End Date: 2020-09-09
IESG Telechat date: Not scheduled for a telechat

Summary: Ready with one process issue, and some assorted nits.

Major issues: None

Minor issues:

The shepherd writeup says:

   The document so far has been approved by the V6OPS working group
   (successful working group last call). The document does not specify
   new protocol, but rather changes to the default parameters in
   existing protocols.

However, the document is Informational, as confirmed by the shepherd writeup. If this is actually updating default parameters in protocols, that sounds like it should either be a Standards Track document or more likely a BCP. As 2026 says:

   The BCP subseries of the RFC series is designed to be a way to
   standardize practices and the results of community deliberations. [...]

   ...[G]ood user
   service requires that the operators and administrators of the
   Internet follow some common guidelines for policies and operations.
   While these guidelines are generally different in scope and style
   from protocol standards, their establishment needs a similar process
   for consensus building.

That sounds like what this is doing, especially with all of the 2119 language in here. Maybe this is Informational because 7084 (and 6204 before it) were Informational, but perhaps 7084 (and other such document) should be BCP as well. Indeed, it sounds like all of these SLAAC operational documents could be in one BCP together. Either way, Informational seems wrong.

Nits/editorial comments:

Throughout the document, it says, "This document RECOMMENDS..." or "This document also RECOMMENDS" or "Additionally, this document RECOMMENDS". RFC 2119 does not use "RECOMMENDS". You can say "CE Routers SHOULD..." or "A Router Lifetime of ND_PREFERRED_LIMIT is RECOMMENDED" or if you must "It is RECOMMENDED that..." (blech, I hate the passive form), since SHOULD and RECOMMENDED are equivalent in 2119, but using the "This document RECOMMENDS..." form is weird and isn't in 2119.

In 3.3, it says:

   o  Upon changes to the advertised prefixes, and after bootstrapping,
      the CE router advertising prefix information via SLAAC SHOULD
      proceed as follows:

But then each of the things under there has a SHOULD or a MUST. The SHOULD here is confusing. Instead, the sentence could simply be:

   o  Upon changes to the advertised prefixes, and after bootstrapping,
   the CE router advertising prefix information via SLAAC proceeds as
   follows:

Similarly:

   This document RECOMMENDS that if a CE Router provides LAN-side DHCPv6
   (address assignment or prefix delegation), the following behavior be
   implemented:

Just make the sentence:

   If a CE Router that provides LAN-side DHCPv6 (address assignment or
   prefix delegation), then: