Session Date/Time: 09 Nov 2021 14:30

sedate

Summary

The sedate working group met to discuss the progress of its single draft document and the overall scope of its work. The primary discussion revolved around whether to expand the working group's scope beyond simple RFC 3339 annotations to include modifications of semantics (e.g., time zone name overriding offset) or entirely new semantics (e.g., floating times). Given the IAB AD's input on rechartering timelines and the needs of the Temporal group, the working group decided on a multi-track approach: continuing swift progress on the current document (annotations), initiating a rechartering discussion for broader semantics, and potentially pursuing an individual submission for the expanded scope in parallel. The timeline for the current document was also adjusted.

Key Discussion Points

Note Well & Code of Conduct: Chairs emphasized the IETF Note Well and guidelines for conduct.
TC39 Liaison Update:
- IAB agreed in early October to establish a liaison to TC39.
- IAB began interviewing volunteer candidates on October 22nd and expects to make progress quickly after IETF 112.
- Chairs committed to keeping the mailing list informed of progress.
Document Scope Discussion:
- Carsten outlined three categories of potential extensions to RFC 3339:
  - A. Annotations: Keep RFC 3339 unchanged, but add information (e.g., human-readable time zone, display hints). Implementations can ignore extensions for perfect interoperability.
  - B. Modifications: Change semantics, where the extension overrides or modifies the base RFC 3339 meaning (e.g., human-readable time zone overriding the numeric offset, particularly for future times where rules might change).
  - C. New Semantics: Concepts not covered by RFC 3339 (e.g., floating times, which require local context for interpretation).
- Debate on B & C: Significant discussion occurred on whether the working group should pursue B and C, given that they fundamentally alter the "fixed point in time" concept of RFC 3339.
  - Arguments were made that if time zone names can override offsets, then the time is not fixed, and thus floating times might also fit.
  - Some argued that "date times" (not necessarily timestamps) are needed for web applications, and standardizing their serialization is valuable.
  - Concern was raised that allowing B could break the promise of backward compatibility/interoperability with 3339 implementations if the semantics differ.
  - The use cases for both "absolute point in time" (e.g., certificate expiry) and "local wall clock time" (e.g., meeting at 1 PM Berlin time) were acknowledged as valid and distinct.
- Charter Constraints: The current charter limits the WG to "extending RFC 3339 time stamps [...] to provide additional information," which aligns primarily with category A.
- Rechartering Implications: The IAB AD, Francesca, noted that rechartering would likely take at least 2.5-3 months, starting in early December, assuming quick agreement on scope and text.
- Temporal Group Needs: The Temporal group indicated that while their API supports these semantics, they can accommodate the current document's scope (A) if needed, and a supplementary document for B/C would be acceptable.
General Format Issues for Extensions:
- Character Encoding: Need a clear decision on ASCII vs UTF-8 for extensions.
- Understanding Unknown Extensions: How to handle recipients that don't understand an extension, especially if it's not just an annotation but modifies meaning (e.g., "must understand" flags).
- Naming the Format: The overall format needs a name.
Time Zone Extension Details:
- Focus on annotation for RFC 3339.
- Considerations for forward compatibility, especially with time zone names being deleted from databases.
Extension Naming and Registries:
- Current draft's mechanism (delegating namespaces to other organizations with separate registries) was seen as overly complicated.
- Proposal to simplify to a single IANA registry, with expert review to prevent "vanity registrations."
- Discussion about single-character namespaces (e.g., u-dash ca for Unicode) and ensuring clarity on how these integrate.
- John Scudder expressed concerns about IANA/IESG dealing with disputes over competing registrations for the same string, suggesting that designated experts might not be equipped for such decisions.
Document Timeline Reality Check: The charter's aspirational December deadline for delivery to the IESG was deemed unrealistic due to holidays and remaining work. A February target was proposed.
Interim Meetings: Proposed to schedule interim meetings to accelerate progress.

Decisions and Action Items

Path Forward: The working group will proceed on three parallel tracks (consensus in session, to be confirmed on mailing list):
1. Existing Document (Annotations): Continue active work to bring the current document (focused on RFC 3339 annotations - scope 'A') to completion as quickly as possible.
2. Rechartering: Initiate discussion on the mailing list about rechartering the working group to formally include broader semantics (types 'B' and 'C'). This discussion should include a very specific and limited scope.
3. Supplementary Document (Individual Submission): Explore the possibility of an individual submission for the 'B'/'B1' (time zone override offset) and/or 'C' (new semantics like floating time) functionality, which could later be adopted as a WG document if rechartering occurs.
Liaison Updates: The chairs will continue to keep the mailing list informed about the progress of the TC39 liaison.
Document Timeline: The aspirational deadline for delivering the current document to the IESG will be revised from December to February next year. This will be proposed to the mailing list for consensus.
Interim Meetings: The chairs will organize an interim meeting in December to accelerate work on the existing document and discuss rechartering. The need for a subsequent interim in January will be decided at the December meeting.

Next Steps

Chairs: Post a summary of the proposed path forward (three parallel tracks, revised timeline) to the sedate mailing list to solicit wider working group discussion and formal consensus.
Chairs: Coordinate with Braun to schedule an interim meeting in December, determining a suitable time for key participants.
Working Group: Continue active work on the existing document (draft-ietf-sedate-datetime-extended) to resolve syntax, encoding (ASCII vs UTF-8), unknown extension handling, and registry issues.
Working Group: Engage in discussion on the mailing list regarding the potential rechartering scope and the approach for broader semantics (B/C).
Editors: Consider drafting text for the rechartering proposal and the potential supplementary document, aligning with the agreed-upon path forward.