NTP Working Group @ IETF 126

Tuesday, 21 July 2026
16:30 - 18:00 CEST (UTC + 2 )

Administrative (Karen)
The WG welcomed Tommy Jensen as the new Area Director (AD),
succeeding Erik Kline
No agenda bashing

NTP over PTP (RFC Editor); currently in the second edit; the final
review (formerly AUTH48) is expected soon.
Roughtime (RFC Editor)
Karen directs attention to the newly launched RFC Editor website.

Status: Open issues are being actively addressed. The working
group aims to initiate a Working Group Last Call (WGLC) before the
end of the year.
Interim Work: A small group meeting is planned for August 2024
to resolve outstanding issues.
Upgrade Concerns: During the Hackathon, Sarah Grant noted a
version mismatch issue during NTPv5 upgrades. Clients sending NTPv4
requests with an indication of NTPv5 support were sometimes ignored
by servers, causing communication to continue in NTPv4. There is a
need to improve the description of this upgrade process in the
document.

The experiment has been updated to use IANA's early allocations.
The pool currently contains about 20 servers.
The latest draft update of draft-ietf-ntp-nts-keyexchange-pool
adds these early identifiers and includes a new section describing
the session flow.
Feedback on the draft is requested, with the goal of progressing the
document soon.

Karen: asked which approach of the outlined approaches awe will run
this experiment a further year.
Ruben: This experiment is running at srv.sectime.org with
experimental support available in patched ntpsec and ntp-rs
(v1.8.1+). The experiment will run for at least a year to gather
data. He expressed reservations about recommending this as a
standard due to DNSSEC verification issues.

Much of the development for draft-ietf-ntp-nts-for-ptp depends on
work currently taking place in the IEEE 1588 security subcommittee.

NTS Pools: Resolved IPv4 handling bugs, added new servers, and
successfully demoed the project.
NTPv5: Sarah Grant developed an interoperability test harness.
Tests revealed upgrade bugs between Chrony and ntp-rs. Work is
ongoing to expand the harness and incorporate NTS for NTPv5.
Roughtime: Performed interoperability testing for TCP and UDP.
Support for TCP remains low across implementations, and forcing
fallback to TCP is difficult. Version mismatches of draft standards
remain a barrier. Sarah Grant suggested waiting for the RFC
publication and version bump before attempting further TCP
interoperability work.

Karen:

PTP Security: Work focuses on addressing vulnerabilities,
establishing NTS as a key management mechanism, and adding security
datasets. This is expected to finalize in the next 6 to 10 months,
after which draft-ietf-ntp-nts-for-ptp will be updated (likely in
the fall).
Client-Server PTP (CSPTP): A relatively new IEEE 1588 effort.
Security for CSPTP behaves similarly to NTP, allowing NTS to map to
it more directly. David Venema has developed an initial proposal for
NTS for CSPTP.

The WG received a liaison request from ITU-T Study Group 17
regarding upcoming 2036–2038 epoch rollovers.
The documents have been shared on the NTP mailing list.
The chairs will meet with IAB liaison coordinators to outline and
prepare a response to ITU-T SG17. The response draft will be
discussed on the mailing list

September 15, 2024: Proposed date for a virtual interim meeting,
focusing on NTPv5 draft resolution