Summer Time Changeover: Automated Daylight Savings
As summer time approaches in many countries, three-quarters of Germans find the changeover a nuisance. However, electronic devices such as smartphones, televisions and laptops make the process easier by automatically adjusting the time at 2 a.m. on the Sunday morning. This process is done through the time zone database of the Internet Assigned Numbers Authority (IANA).
The Time Zone Database – often abbreviated as tz and also known as “zoneinfo” – contains information on all time zones on earth. It is primarily intended for use in application programs and operating systems. The freely available tz database is updated about once a month and is used by Unix and Linux, various websites and Java applications.
The automated time change is the result of intensive and careful preparatory work by a group of volunteers who coordinate the time zones in a forum run by the IANA. The IT core of the system is a machine-readable description of the time zones including all time changes, defined by an extensive set of mathematical rules and formulas.
The makers of the database attempt to record all historical time zones and all changes in civil time since 1970, including leap seconds. The experts behind it continuously follow reports on changes in time zones and enter them into the database.
The project goes back to Arthur David Olson, who maintained it on his own for years. Today it is led by computer scientist Paul Eggert of the University of California Los Angeles and software engineer Tim Parenti of Carnegie Mellon University. After a copyright dispute, the database was placed under the IANA in order to create legal certainty.
Alexander Rabe, Managing Director of the eco Association of the Internet Industry, sees the database as an example of the added value that can arise from the cooperation of many players from the online industry, the non-profit sector, and politics, as well as private individuals.
