NTP Working Group @ IETF 126

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

1. Welcome, Note Well, Agenda bash

https://datatracker.ietf.org/meeting/126/materials/slides-126-ntp-ntp-wg-chair-slides-00

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

2. NTP WG Documents (beyond the working group)

• 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.

3. NTPv5

https://datatracker.ietf.org/doc/draft-ietf-ntp-ntpv5/

• 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.

4. NTS Pool Experiment (David)

https://datatracker.ietf.org/doc/draft-ietf-ntp-nts-keyexchange-pool/
David provided an update on the ongoing NTS pool experiment running on
sectime.org.

• 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.

5. NTS Pools Using DNS (Ruben)

Presentation by Ruben Ruben Nijveld:
https://datatracker.ietf.org/doc/slides-126-ntp-nts-server-pools-using-dns-srv-records/

Discussion

• 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.

6. NTS for PTP (Karen O'Donoghue)

https://datatracker.ietf.org/doc/draft-ietf-ntp-nts-for-ptp/
Status update:

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

7. Hackathon Update (David Venhoek)

Presentation by David Venhoek:
https://datatracker.ietf.org/doc/slides-126-ntp-hackathon/

• 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.

8. 1588 Update (Karen O'Donoghue)

Presentation by Karen O'Donoghue
https://datatracker.ietf.org/meeting/126/materials/slides-126-ntp-ieee-1588-update-00

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.

9. ITU Liaison on NTP rollover (Karen O'Donoghue)

• 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

10. AOB

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