IETF Last Call Review of draft-ietf-uta-tls13-iot-profile-21
review-ietf-uta-tls13-iot-profile-21-tsvart-lc-duke-2026-06-08-00

This document has been reviewed as part of the transport area review team's
ongoing effort to review key IETF documents. These comments were written
primarily for the transport area directors, but are copied to the document's
authors and WG to allow them to address any issues raised and also to the IETF
discussion list for information.

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There are some transport implications in this draft, particularly Section 10 on
timers and ACKs. However, the timer guidance is consistent with BCP 233/RFC 8961.

The draft relies on RFC 6520 for MTU discovery and keepalive, so it is not
inventing new standards here. However, instead of Section 9 saying that
"the discussion is applicable", it's important to actually state the normative
requirement, which I presume is that the RFC 6520 heartbeat mechanism is 
RECOMMENDED.

Nit:
In section 8, "Implementations may not support these suites", would be a better
phrased as "might not."