Network Working Group                                            E. Lear
Internet-Draft                                        Cisco Systems GmbH
Intended status: BCP                                           P. Eggert
Expires: July 31, 2011                                              UCLA
                                                        January 27, 2011

         IANA Procedures for Maintaining the Timezone Database


   ATTENTION: This memo contains a DRAFT proposal for the IANA to assume
   operational responsibilities relating to the management of the
   Timezone (TZ) Database.  The authors seek comment and review of this
   proposal.  No action will be taken without rough consensus of the TZ

   Timezone information serves as a basic protocol element in protocols,
   such as the calendaring suite and DHCP.  The Timezone (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 IANA 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 timezone community.  The intent of this memo is, to
   the extent possible, document existing practice and provide a means
   to ease succession.

Status of this Memo

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   provisions of BCP 78 and BCP 79.

   Internet-Drafts are working documents of the Internet Engineering
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   This Internet-Draft will expire on July 31, 2011.

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Copyright Notice

   Copyright (c) 2011 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

   ATTENTION: This memo contains a DRAFT proposal for the IANA to assume
   operational responsibilities relating to the management of the
   Timezone (TZ) Database.  The authors seek comment and review of this
   proposal.  No action will be taken without rough consensus of the TZ

   The IETF has specified several standards that make use of timezone
   information.  Timezone names are used in DHCP to configure devices
   with correct local time [RFC4833].  Timezone names can appear in the
   TZID field of VEVENTs [RFC5545].  The normative reference for these
   values is the TZ Database [TZDB].  Since the early 1980s, that
   database, which has been in use on nearly all UNIX systems, Java
   systems, and other sorts of systems has been hosted at the National
   Institutes of Health.  The database consists of both historic and
   current entries for geographies throughout the world.  Associated
   with the database is a reference implementation of functions that can
   be used to convert time values.

   The database has been maintained by volunteers who participate in a
   mailing list that is 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 continue.

   The IANA provides registry services to the Internet community.  Those
   registries are coordinated by technical experts who are designated by
   the Internet Engineering Steering Group (IESG).  The IANA is also

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   well suited as a distribution platform for the TZ Database itself.

   The IANA has for quite some time had the capability to maintain
   designated expert mailing lists.  The TZ mailing list would fit
   nicely just as such a list.

1.1.  Terminology

   The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
   document are to be interpreted as described in RFC 2119 [RFC2119].

   TZ Database:  The TimeZone Database, sometimes referred to as the
      Olson Database.  This database consists of information about
      offsets from UTC for different localities, including daylight
      saving time (DST) transition information.
   TZ Coordinator:  The person or people who maintain and manage release
      of the TZ Database.  The TZ coordinator also has responsibility
      for maintaining the TZ mailing list.  The TZ coordinator is an
      IANA Designated Expert, as defined in Section 3.2 of [RFC5226].
      Roughly speaking, this means that the IESG will choose one or more
      experts to manage the TZ database, code, and mailing list.
   TZ mailing list:  The forum where matters relating to the TZ database
      and supporting code are discussed.

   The rest of this document specifies the following:

   1.  Transferring and maintenance of the TZ mailing list;
   2.  Procedures for selecting a technical expert for the technical
       expert who will play the role of coordinator and release manager
       for the TZ database;
   3.  Procedures for updating the TZ database;
   4.  Maintenance and ownership of reference code; and
   5.  Ownership of the database.

2.  The TZ Mailing List

   For many years the TZ mailing list at the NIH has been the forum
   where discussion of changes to the TZ database and support files
   would take place.  In addition, the TZ mailing list is used to
   announce releases of the database.  Currently the TZ mailing list is
   administered by the TZ coordinator.

   This list membership will be transitioned to the IANA mail server.
   The TZ coordinator will continue to manage the list.  While the TZ
   coordinator may establish other rules of governance for the list,
   members of that list will be informed that a condition of

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   participating on the list is that all contributions to the list are
   released to the public domain, and that by placing their contribution
   in the public domain, contributors waive forever any intellectual
   property claims.

   The list will be used just as it has been, to learn of, discuss, and
   confirm TZ definition changes, as well as an announcement list for
   new versions of the database.

3.  Making Updates to the TZ Database

   Updates to the TZ database are made by the TZ coordinator in
   consultation with the TZ mailing list.  TZ coordinator is empowered
   to decide, as the designated expert, appropriate changes, but SHOULD
   take into account views expressed on the mailing list.

   The TZ coordinator will also decide the timing of database releases.
   The release itself today consists of several archive files that are
   downloaded from a well known location.

   Moving forward, the TZ database and supporting code SHOULD be signed
   prior to release using a well known key, along with any appropriate
   supporting information and distributed from a well known location
   that is advertised by IANA in a manner of its choosing.

   The criteria for updates to the database are as follows:

   1.  New keys are only to be created when the region a key was
       envisioned to cover is not accurately reflected by an existing
   2.  In order to correct historical inaccuracies, a new key MAY be
       added when it is necessary to indicate what was the consensus
       view at given time and location.  Such keys are usually not added
       when the inaccuracy was prior to 1970.
   3.  Changes to existing entries SHALL reflect the consensus on the
       ground in the region covered by that entry.

   To be clear, the TZ coordinator SHALL NOT set timezone policy policy
   for a region but use judgment and whatever available sources exist to
   assess what the average person on street would think the time
   actually is, or in case of historical corrections, was.

4.  Selecting or Replacing a TZ Coordinator

   From time to time it will be necessary to appoint a new TZ
   Coordinator.  This could occur for a number of reasons:

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   o  The coordinator is retiring (as Arthur Olson is) or has announced
      that he or she will be unable to continue to perform the function;
   o  The coordinator is missing or has died;
   o  The coordinator is not performing the function in accordance with
      community wishes.

   In any of these cases, members of the community should raise the
   issue on the TZ list.  If a rough consensus can be formed easily, and
   quickly, then the results should be presented to the IESG for comment
   and review.  The IESG selects the TZ coordinator(s).  The IESG will
   use rough consensus of the TZ mailing list as their primary guide to
   further action, when it exists, and whatever other means they have at
   their disposal, when rough consensus cannot be found.

5.  Appealing Database Decisions

   The TZ coordinator makes decisions based on expertise, as well as
   with guidance from the TZ mailing lists.  While individual decisions
   MAY be appealed to the IESG, the IESG MUST give great deference to
   the designated expert in its considerations.  In particular,
   apellants MUST show material harm from the decision, and that the
   decision is materially in error.  The IESG is not a normal avenue for
   appeals of specific decisions of the coordinator, but rather a last
   resort when a coordinator is thought not to be functioning in an
   appropriate way.

   N.B., the coordinator is a function, and may be filled by one or more
   people, as the community sees fit.

6.  Maintenance and Distribution of Reference Code

   Currently the maintainer of the TZ database also maintains reference
   code, most of which is public domain.  Several files from this
   software are currently distributed under license.  Where they exist,
   licenses SHALL NOT be changed.  IANA SHALL allow for the downloading
   of this reference code.  The reference implementation shall be
   distributed along with an associated cryptographic signature of an
   identity that IANA will publish.

7.  Database Ownership

   The database itself is public domain.  Should claims be made and
   substantiated against the database, the IANA will act in accordance
   with all competent court orders.  No ownership claims will be made by
   IANA or the IETF Trust on the database or the code.  Any person

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   making a contribution to the database or code waives all rights to
   future claims.

8.  IANA Considerations

   The IANA SHALL assist the IESG, as required, in filling of the TZ
   Coordinator, based on the procedures set forth above.  The IANA SHALL
   act as a repository for the TZ database and associated reference
   code.  The database coordinator SHALL be named by the IESG as
   described above, and will act as the maintainer of the database and
   code, as described above.  The IANA SHALL provide the TZ coordinator
   with appropriate access to maintain the database, as well as
   necessary tooling that may be required, so long as no direct software
   costs are incurred.  Both current and historical versions of the
   database will be stored and distributed via HTTP/HTTPs.  IANA will be
   operationally responsible for the security of the system upon which
   the database resides.

   The IANA SHALL also maintain a cryptographic identity that is used to
   sign the database, and that will survive a change of coordinators.

9.  Security Considerations

   The distribution of the database is currently not secured.  This memo
   states that moving forward the TZ database SHOULD be distributed with
   a valid cryptographic signature.

10.  Acknowledgments

   The authors would like to thank the TZ mailing list for their
   remarkable achievements over the many years.  Thanks also to Marshall
   Eubanks, S. Moonesamy, Peter Saint-Andre, Alexey Melenkov, Tony
   Finch, Elwin Davies, Alfred Hoenes, and Ted Hardie for the
   improvements they made to this document.  A special acknowledgment
   should be given to Arthur David Olson for his excellent stewardship.

11.  Normative References

   [RFC2119]  Bradner, S., "Key words for use in RFCs to Indicate
              Requirement Levels", BCP 14, RFC 2119, March 1997.

   [RFC4833]  Lear, E. and P. Eggert, "Timezone Options for DHCP",
              RFC 4833, April 2007.

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   [RFC5226]  Narten, T. and H. Alvestrand, "Guidelines for Writing an
              IANA Considerations Section in RFCs", BCP 26, RFC 5226,
              May 2008.

   [RFC5545]  Desruisseaux, B., "Internet Calendaring and Scheduling
              Core Object Specification (iCalendar)", RFC 5545,
              September 2009.

   [TZDB]     Eggert, P. and A. Olson, "Sources for Time Zone and
              Daylight Saving Time Data",

Appendix A.  Changes

   o  02: Separate out from RFC5226 a bit; Simplify language around
      submissions; host list to IANA; spelling corrections; clarify here
      and there.
   o  01: Proper reference to RFC5226, add acknowledgments, several
   o  Initial Revision

Authors' Addresses

   Eliot Lear
   Cisco Systems GmbH
   Richtistrasse 7
   Wallisellen, ZH  CH-8304

   Phone: +41 1 878 9200

   Paul Eggert
   Computer Science Department
   4532J Boelter Hall
   Los Angeles, CA  90095

   Phone: +1 310 267 2254

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