Early Review of draft-ietf-intarea-multicast-application-port-04
review-ietf-intarea-multicast-application-port-04-opsdir-early-linkova-2026-03-18-00

Hi,

I have been selected as the Operational Directorate (opsdir) reviewer for this
Internet-Draft.

The Operational Directorate reviews all operational and management-related
Internet-Drafts to ensure alignment with operational best practices and that
adequate operational considerations are covered.

A complete set of _"Guidelines for Considering Operations and Management in
IETF Specifications"_ can be found at
https://datatracker.ietf.org/doc/draft-ietf-opsawg-rfc5706bis/.

While these comments are primarily for the Operations and Management Area
Directors (Ops ADs), the authors should consider them alongside other feedback
received.

- Document: [draft-ietf-intarea-multicast-application-port-04]

- Reviewer: [Jen Linkova]

- Review Date: [March 19 2026]

- Intended Status: [Standards Track]

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## Summary

- Ready: No issues found. This document is ready for publication.

## General Operational Comments Alignment with RFC 5706bis

I believe the document would benefit from an Operational Consideration section
discussing the migration path. Maybe just a few sentences saying that if a
unicast application is using this port currently, clients might gradually stop
ability to connect to it, as those client hosts become compliant with this
document?

## Major Issues

 > No major issues found.

---

## Minor Issues

The document currently says:

"The Multicast Application Port SHALL NOT be used as a destination port for any
non-multicast messages. It MAY be used as a source port by an application that
exclusively uses multicast messages. If any application messages are unicast,
then a different port should be used for the source port."

- Is 'should' in the last sentence intentionally lower-case?

Is it allowed (MAY/SHOULD NOT or even MUST NOT) to send a unicast message from
src port == mcast-app-port? Or is it intentional that the case of a unicast
message with src port == mcast-app-por is unspecified? (it would also explains
why Section 3 says that "Hosts SHALL discard all incoming, non-multicast
packets that use this destination port" but doesn't say anything about packets
with that source port).