Daylight Saving Time and Time Zones

General Interest

CalConnect Time Zone Discussion Public Mailing LIst

CalConnect has implemented this public discussion list,  intended for discussion on timezones, especially in calendaring and scheduling. A particular focus is on exchanging issues, challenges, and best practices related to timezone changes. The intended audience for this list is hence not only technical, but also involves decision makers involved in the political process of changing timezones.

Procedures for Maintaining the Time Zone Database RFC 6557

Time zone information serves as a basic protocol element in protocols, such as the calendaring suite and DHCP. The Time Zone (TZ) Database specifies the indices used in various protocols, as well as their semantic meanings, for all localities throughout the world. This database has been meticulously maintained and distributed free of charge by a group of volunteers, coordinated by a single volunteer who is now planning to retire. This memo specifies procedures involved with maintenance of the TZ database and associated code, including how to submit proposed updates, how decisions for inclusion of those updates are made, and the selection of a designated expert by and for the time zone community. The intent of this memo is, to the extent possible, to document existing practice and provide a means to ease succession of the database maintainers.

Time Zone Data Distribution Service RFC 7808

This document defines a time zone data distribution service that allows reliable, secure and fast delivery of time zone data to client systems such as calendaring and scheduling applications or operating systems.


European Union Summer Time Proposal (2018-2019)

CalConnect calls on EU to reconsider timeline for proposed seasonal time changes

Press Release about CalConnect's Advisory Notice concerning the EU Summer Time Proposal

CalConnect Advisory Notice on EU Summer Time Proposal

This document, developed shortly after the EU announcement, is an  Advisory Notice expressing concern about the amount of time before the proposal would take effect, and recommending additional time for providers, consumers and governments to prepare for the impact.


Extended Daylight Saving Time Proposal and Implementation (2005-2008)

CalConnect EDST Reflections and Recommendations

This document, prepared by the CalConnect DST Ad Hoc Committee, reflects on the impact of the Extended Daylight Savings Time change to the start of DST in the United States to March 11, 2007, and provides recommendations for the coming change back on November 4, plus longer term recommendations for timezone management in the future.

Extended Daylight Saving Time Review and Considerations:

This document provides a review of the Daylight Saving Time changes and the potential impact of this change on computer systems and devices. It is intended as a review and reference for users and in particular for systems administrators who may need to make necessary updates to their systems.

Extended Daylight Saving Time Links, Advisories and Changes:

This document is a compilation of links to vendor-provided advisories, technical notes, change documents, and the like. Its primary purpose is to try and consolidate in one place links to references for Calendaring and Scheduling systems and major underlying operating systems, but links for related products and services will be provided when possible.

We realize that this compilation is far from complete, and is only as useful as it is inclusive, and solicit additional information which belongs in this compiliation. Please send references and URLs to DST Referrals.

Extended Daylight Saving Time Advisory Notice:

This document, developed just prior to the signing of the Energy Policy Act into law, was an advisory intended to explain the impact of the Act's proposed changes to Daylight Saving Time and CalConnect's concerns as to that impact and the necessary actions which needed to be taken by vendors and customers prior to the first DST change coming into effect.