IETF Last Call Review of draft-ietf-ntp-over-ptp-05
review-ietf-ntp-over-ptp-05-genart-lc-sparks-2025-09-24-00

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Document: draft-ietf-ntp-over-ptp-05
Reviewer: Robert Sparks
Review Date: 2025-09-24
IETF LC End Date: 2025-09-24
IESG Telechat date: Not scheduled for a telechat

Summary: Mostly ready but with a few issues to consider before publication as a
Proposed Standard RFC.

I appreciate that this work has had such open and careful coordination with
IEEE.

Major issues:

It's been awhile since I dove deeply into NTP, but isn't it possible for
responses to be larger than requests in normal operation? This draft requires
that the PTP message containing the NTP response MUST NOT be larger than the
PTP message containing the NTP request. What's supposed to happen if the NTP
response _is_ bigger than the request? Consider either a brief exploration of
this, or an explanation of why it won't be an issue.

Minor issues:

Requiring that a PTP message MUST conform to any future version of the PTP
specification doesn't make sense. It borders on the IETF telling IEEE how they
can evolve their protocol by implying a requirement that future versions of PTP
remain backward compatible enough for this encapsulation to work. While a
future where that's not the case is vanishingly unlikely, it's not ours to
require. I think the most you can say is that it is expected that this
encapsulation will be useful with future versions of the PTP specification
without modification.

Nits/editorial comments:

Please reference BCP14 rather that RFC2119.