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Serialising Extended Data About Times and Events (sedate)

WG Name Serialising Extended Data About Times and Events
Acronym sedate
Area Applications and Real-Time Area (art)
State Active
Charter charter-ietf-sedate-01 Approved
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Additional resources GitHub Repository
Zulip Stream
Personnel Chairs Bron Gondwana, Mark McFadden
Area Director Francesca Palombini
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Charter for Working Group

RFC 3339 defines a text format as a profile of ISO 8601 that can reliably
express an instant in time, either in UTC or in a local time along with the
offset against UTC. However, datetime data often has additional context, such
as the timezone or calendar system that was in use when that instant was

Particularly when using times for interval, recurrence, or offset calculations,
it is necessary to know the context in which the timepoint exists. It would be
valuable to have a standard text serialisation format for this contextual data.
This working group will develop and publish a format meeting that requirement,
subject to the additional constraints described below.

* This format must be able to round-trip through intermediate systems which do
not understand the full context.

* Systems which don’t understand all the contextual fields must still be able
to reliably extract the instant in time.

This format will be a companion to RFC 3339 rather than a replacement,
embedding unaltered RFC 3339 data in a way that makes it easy to parse just the
datetime data independently of the context.

Changes to RFC 3339 are explicitly outside the charter for this working group.
If a need for an RFC 3339bis emerges, this group must recharter before
performing that work. In this case, the changes to RFC 3339 will need to be
clearly motivated, evaluated and precisely scoped during the rechartering
process, and will need to make only changes that keep the timestamp
specification a profile of current versions of ISO 8601. Stability of the RFC
timestamp format is important to existing IETF protocols and the Internet
generally, and any rechartering process should frown on anything that would
invalidate the existing timestamp format.

The working group will coordinate with ECMA International TC39 and ISO/TC 154
to ensure that this work remains a strict extension of ISO 8601 and its various
parts rather than becoming a conflicting standard.


Date Milestone Associated documents
Jun 2022 Submit extended date and time draft to the IESG for publication draft-ryzokuken-datetime-extended

Done milestones

Date Milestone Associated documents
Done Adopt a draft for extended date and time handling draft-ryzokuken-datetime-extended