Calendaring Extensions to WebDAV (CalDAV): Time Zones by Reference
RFC 7809
Document | Type |
RFC - Proposed Standard
(March 2016; No errata)
Updates RFC 4791
|
|
---|---|---|---|
Author | Cyrus Daboo | ||
Last updated | 2016-03-31 | ||
Replaces | draft-daboo-caldav-timezone-ref | ||
Stream | IETF | ||
Formats | plain text html pdf htmlized bibtex | ||
Stream | WG state | Submitted to IESG for Publication | |
Document shepherd | Eliot Lear | ||
Shepherd write-up | Show (last changed 2015-09-22) | ||
IESG | IESG state | RFC 7809 (Proposed Standard) | |
Consensus Boilerplate | Yes | ||
Telechat date | |||
Responsible AD | Barry Leiba | ||
Send notices to | (None) | ||
IANA | IANA review state | Version Changed - Review Needed | |
IANA action state | RFC-Ed-Ack |
Internet Engineering Task Force (IETF) C. Daboo Request for Comments: 7809 Apple Updates: 4791 March 2016 Category: Standards Track ISSN: 2070-1721 Calendaring Extensions to WebDAV (CalDAV): Time Zones by Reference Abstract This document defines an update to the Calendaring Extensions to WebDAV (CalDAV) calendar access protocol (RFC 4791) to allow clients and servers to exchange iCalendar data without the need to send full time zone data. Status of This Memo This is an Internet Standards Track document. This document is a product of the Internet Engineering Task Force (IETF). It represents the consensus of the IETF community. It has received public review and has been approved for publication by the Internet Engineering Steering Group (IESG). Further information on Internet Standards is available in Section 2 of RFC 5741. Information about the current status of this document, any errata, and how to provide feedback on it may be obtained at http://www.rfc-editor.org/info/rfc7809. Copyright Notice Copyright (c) 2016 IETF Trust and the persons identified as the document authors. All rights reserved. This document is subject to BCP 78 and the IETF Trust's Legal Provisions Relating to IETF Documents (http://trustee.ietf.org/license-info) in effect on the date of publication of this document. Please review these documents carefully, as they describe your rights and restrictions with respect to this document. Code Components extracted from this document must include Simplified BSD License text as described in Section 4.e of the Trust Legal Provisions and are provided without warranty as described in the Simplified BSD License. Daboo Standards Track [Page 1] RFC 7809 CalDAV Time Zone Extension March 2016 Table of Contents 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 2 2. Conventions Used in This Document . . . . . . . . . . . . . . 3 3. Time Zones by Reference . . . . . . . . . . . . . . . . . . . 3 3.1. New Server Behavior . . . . . . . . . . . . . . . . . . . 4 4. New Client Behavior . . . . . . . . . . . . . . . . . . . . . 7 5. New WebDAV Properties . . . . . . . . . . . . . . . . . . . . 8 5.1. CALDAV:timezone-service-set . . . . . . . . . . . . . . . 8 5.2. CALDAV:calendar-timezone-id . . . . . . . . . . . . . . . 9 6. XML Element Definitions . . . . . . . . . . . . . . . . . . . 9 6.1. CALDAV:calendar-query XML Element . . . . . . . . . . . . 9 6.2. CALDAV:timezone-id XML Element . . . . . . . . . . . . . 10 7. Additional Message Header Fields . . . . . . . . . . . . . . 10 7.1. CalDAV-Timezones Request Header Field . . . . . . . . . . 10 8. Security Considerations . . . . . . . . . . . . . . . . . . . 11 9. Privacy Considerations . . . . . . . . . . . . . . . . . . . 11 10. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 11 10.1. CalDAV-Timezones . . . . . . . . . . . . . . . . . . . . 11 11. References . . . . . . . . . . . . . . . . . . . . . . . . . 12 11.1. Normative References . . . . . . . . . . . . . . . . . . 12 11.2. Informative References . . . . . . . . . . . . . . . . . 12 Acknowledgments . . . . . . . . . . . . . . . . . . . . . . . . . 13 Author's Address . . . . . . . . . . . . . . . . . . . . . . . . 13 1. Introduction The CalDAV [RFC4791] calendar access protocol allows clients to access calendar data stored on a server in the iCalendar [RFC5545] data format. In iCalendar, calendar data that uses local time in any of its date and/or time values is specified as a date-time value in combination with a time zone identifier ("TZID" property parameter). The time zone identifier refers to a time zone definition (a "VTIMEZONE" component) that has all of the rules required to determine local-time UTC offsets for the corresponding time zone. In many cases, these "VTIMEZONE" components can be larger, octet-wise, than the events or tasks that make use of them. However, iCalendar currently requires all iCalendar objects ("VCALENDAR" components) that refer to a time zone via its identifier to also include the corresponding "VTIMEZONE" component. This leads to inefficiencies in the CalDAV protocol because large amounts of "VTIMEZONE" data are continuously being exchanged, and for the most part these time zone definitions are unchanging. This is particularly problematic for mobile or limited devices, with limited network bandwidth, CPU, and energy resources. Daboo Standards Track [Page 2] RFC 7809 CalDAV Time Zone Extension March 2016Show full document text