Posted March 15, 2019

CalConnect held a timezone workshop on February 5th 2019, in conjunction with its meeting in Zurich. This workshop was initiated to discuss the EU’s proposal allowing member states the option to select permanently remain on either "Standard Time" or "Summer Time", addressing issues of governance and challenges of technical implementation. Workshop attendees represented a number of major vendors and the IANA tz database.

Discussions revolved around three central themes:

Currently there is no structured way for a government’s decisions about timezone changes to be propogated to maintainers of timezone data. Changes are typically collated from crowdsourced information such as newspaper reports and legal documents and manually transcribed into the timezone databases used worldwide. An upcoming effort within the International Standards Organization (ISO) seeks to define a standard and registry for advanced notification of timezone changes; CalConnect is involved in this work an ISO liaison.

Updates to timezone information are commonly distrubted by copying timezone databases to devices and systems. A given system may have multiple copies of timezone information across its operating system, runtimes, and database systems, requiring a reboot in order for changes to take effect. Vendors and operators struggle to balance timely delivery against qualification and quality testing.

Given the lack of structured formats and rigorous propagation mechanisms, much of the work in tracking changes and additions is a volunteer effort. These issues led to the development of the Time Zone Data Distribution Standard (RFC 7808) and Time Zone Information Format (RFC 8536) standards. However, these standards have yet to be meaningfully adopted.

In a previous statement released 2018-10-30, CalConnect urges the EU to provide a transition period of at least one year (12 months) following a final decision. This guidance draws upon CalConnect’s extensive work during the United States debate of 2005-2008 regarding changes to the Daylight Saving Time start and end dates, and the lessons learned from that transition.

A complete account of CalConnect’s 2019 meeting in Zurich is available at standards.calconnect.org.

CalConnect, The Calendaring & Scheduling Consortium, is comprised of technology vendors and end-user organizations focused on the areas of date and time, calendaring, and scheduling. It pursues the wide availability of truly interoperable collaboration tools through the use of open standards.