Calendaring Extensions

The information below is for a proposed recharter. The current approved charter is version 01
Document Proposed charter Calendaring Extensions WG (calext)
Title Calendaring Extensions
Last updated 2022-01-21
State Start Chartering/Rechartering (Internal Steering Group/IAB Review) Rechartering
WG State Active
IESG Responsible AD Francesca Palombini
Charter Edit AD Francesca Palombini
Telechat date On agenda of 2022-02-03 IESG telechat
Has enough positions to pass.
Send notices to (None)


The CALEXT working group is chartered to maintain and extend the
specifications for formats and protocols related to calendaring and contacts
within the IETF, starting from the basis of:

- CalDAV (RFC 4791)
- iCalendar (RFC 5545)
- iTIP (RFC 5546)
- iMIP (RFC 6047)
- VCARD (RFC 6350)
- CardDAV (RFC 6352)
- JSCalendar (RFC 8984)
- JSContact (draft-ietf-jmap-jscontact)

and the many existing extensions and companion documents to these.

This working group is envisaged to be long-running, and deal with a steady slow
flow of changes.  Experience has shown that these specifications are still
seeing significant need for updates, as new use-cases are identified and user
requirements change.

This working group will do the following:

- maintain existing standards and proposed standards, processing errata and
refreshing them as required - evaluate and develop extensions to the existing
standards to provide for new use-cases where there is demand - generate
documents describing existing vendor extensions which are in common usage, and
likely to be encountered in the wild.

The working group will work under the following parameters:

- The extensions developed are expected to be backwards-compatible with the
existing standards. Incompatibilities must be identified, minimized, and
justified. - Any extensions to icalendar or jscalendar must include a
representation in both formats, and define a robust mapping between them. - Any
extensions to vcard or jscontact must include a representation in both formats,
and define a robust mapping between them. - All calendar extensions must
examine their impact on the iTIP protocol (RFC 5546), and define any necessary
extensions to iTIP to accommodate such impact.

The working group will maintain relationships with other working groups:

- HTTPBIS and HTTPAPI: when extending the CalDAV or CardDAV protocols to ensure
that changes are consistent with good http practices. - JMAP: when making
updates to JSCalendar and JSContact to ensure that the changes are compatible
with the JMAP methods for managing data in these formats. - EXTRA, DMARC and
EMAILCORE: for changes related to iTIP delivery via email. - TZDIST and SEDATE
for date, time, and timezone related issues. - Other IETF working groups as
appropriate, when their work interacts with ours. - Other standards
organisations like CalConnect and M3AAWG that are doing work in the same fields.

The following are out of scope for the working group:

- Any attempt to develop non-Gregorian calendar systems/calculations.
- Work which is in scope for any other ART area working group, and better
suited to that group. - Work which is unrelated to anything that this group is
currently maintaining.

Proposed milestones


Date Milestone
1 Jul 2022 Submit calendar series document to IESG for publication
1 Jun 2022 Submit Serverside Subscription draft to IESG for publication
1 Jun 2022 Submit vpoll document to IESG for publication
1 Apr 2022 Submit JSON Contact document to IESG
1 Apr 2022 Submit JSCalendar mapping document to IESG for publication
1 Jan 2022 Submit task draft to IESG
1 Jan 2022 Submit Subscription Upgrade document to IESG for publication