Procedures for Maintaining the Time Zone Database
RFC 6557

Document Type RFC - Best Current Practice (February 2012; No errata)
Also known as BCP 175
Was draft-lear-iana-timezone-database (individual in app area)
Last updated 2015-10-14
Stream IETF
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Stream WG state (None)
Consensus Unknown
Document shepherd No shepherd assigned
IESG IESG state RFC 6557 (Best Current Practice)
Telechat date
Responsible AD Peter Saint-Andre
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Internet Engineering Task Force (IETF)                           E. Lear
Request for Comments: 6557                            Cisco Systems GmbH
BCP: 175                                                       P. Eggert
Category: Best Current Practice                                     UCLA
ISSN: 2070-1721                                            February 2012

           Procedures for Maintaining the Time Zone Database


   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

Status of This Memo

   This memo documents an Internet Best Current Practice.

   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
   BCPs 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

Lear & Eggert             Best Current Practice                 [Page 1]
RFC 6557           Maintaining the Time Zone Database      February 2012

Copyright Notice

   Copyright (c) 2012 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
   ( 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.

1.  Introduction

   The IETF has specified several standards that make use of time zone
   information.  Time zone names are used in DHCP to configure devices
   with correct local time [RFC4833].  Time zone names can appear in the
   TZID field of calendaring VEVENTs [RFC5545].  The normative reference
   for these values is the TZ Database [TZDB].  From the early 1980s
   through 2011, that database, which has been in use on nearly all UNIX
   systems, Java systems, and other sorts of systems, was hosted at the
   U.S. National Institutes of Health (NIH).  The database consists of
   both historic and current entries for geographies throughout the
   world.  Associated with the database is a reference implementation of
   ISO/IEC 9899 C [ISO9899C] and IEEE 1003.1 [IEEE1003.1] POSIX time
   functions that can be used to convert time values.

   The database was previously maintained by volunteers who participated
   in the <> mailing list that was also hosted at
   the NIH.  The database itself is updated approximately twenty times
   per year, depending on the year, based on information these experts
   provide to the maintainer.  Arthur David Olson has maintained the
   database, coordinated the mailing list, and provided a release
   platform since the database's inception.  With his retirement now
   approaching, it is necessary to provide a means for this good work to

   The time zone community has requested that the IETF adopt the ongoing
   maintenance of the Time Zone Database.  The time zone community would
   like the IETF to maintain it in a consistent fashion to its
   administration of the Internet protocol parameters and values.

Lear & Eggert             Best Current Practice                 [Page 2]
RFC 6557           Maintaining the Time Zone Database      February 2012

1.1.  Terminology

   The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
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