Network Working Group                                         R. McGowan
Request for Comments: 3718                                       Unicode
Category: Informational                                    February 2004
Network Working Group                                         R. McGowan
Request for Comments: 3718                                       Unicode
Category: Informational                                    February 2004

A Summary of Unicode Consortium Procedures, Policies, Stability, and Public Access


Status of this Memo


This memo provides information for the Internet community. It does not specify an Internet standard of any kind. Distribution of this memo is unlimited.


Copyright Notice


Copyright (C) The Internet Society (2004). All Rights Reserved.




This memo describes various internal workings of the Unicode Consortium for the benefit of participants in the IETF. It is intended solely for informational purposes. Included are discussions of how the decision-making bodies of the Consortium work and their procedures, as well as information on public access to the character encoding & standardization processes.


1. Introduction
1. 介绍

This memo describes various internal workings of the Unicode Consortium for the benefit of participants in the IETF. It is intended solely for informational purposes. Included are discussions of how the decision-making bodies of the Consortium work and their procedures, as well as information on public access to the character encoding & standardization processes.


2. About The Unicode Consortium
2. 关于Unicode联盟

The Unicode Consortium is a corporation. Legally speaking, it is a "California Nonprofit Mutual Benefit Corporation", organized under section 501 C(6) of the Internal Revenue Service Code of the United States. As such, it is a "business league" not focussed on profiting by sales or production of goods and services, but neither is it formally a "charitable" organization. It is an alliance of member companies whose purpose is to "extend, maintain, and promote the Unicode Standard". To this end, the Consortium keeps a small office, a few editorial and technical staff, World Wide Web presence, and mail list presence.

Unicode联盟是一家公司。从法律上讲,它是一家“加州非营利性互惠公司”,根据《美国国税局法典》第501 C(6)节组建。因此,它是一个“商业联盟”,不专注于通过销售或生产商品和服务获利,但也不是一个正式的“慈善”组织。它是一个成员公司联盟,其目的是“扩展、维护和推广Unicode标准”。为此,该联盟保留了一个小型办公室、一些编辑和技术人员、万维网和邮件列表。

The corporation is presided over by a Board of Directors who meet annually. The Board is comprised of individuals who are elected annually by the full members for three-year terms. The Board appoints Officers of the corporation to run the daily operations.


Membership in the Consortium is open to "all corporations, other business entities, governmental agencies, not-for-profit organizations and academic institutions" who support the Consortium's purpose. Formally, one class of voting membership is recognized, and dues-paying members are typically for-profit corporations, research and educational institutions, or national governments. Each such full member sends representatives to meetings of the Unicode Technical Committee (see below), as well as to a brief annual Membership meeting.


3. The Unicode Technical Committee
3. Unicode技术委员会

The Unicode Technical Committee (UTC) is the technical decision making body of the Consortium. The UTC inherited the work and prior decisions of the Unicode Working Group (UWG) that was active prior to formation of the Consortium in January 1991.


Formally, the UTC is a technical body instituted by resolution of the board of directors. Each member appoints one principal and one or two alternate representatives to the UTC. UTC representatives frequently do, but need not, act as the ordinary member representatives for the purposes of the annual meeting.


The UTC is presided over by a Chair and Vice-Chair, appointed by the Board of Directors for an unspecified term of service.


The UTC meets 4 to 5 times a year to discuss proposals, additions, and various other technical topics. Each meeting lasts 3 to 4 full days. Meetings are held in locations decided upon by the membership, frequently in the San Francisco Bay Area. There is no fee for participation in UTC meetings. Agendas for meetings are not generally posted to any public forum, but meeting dates, locations, and logistics are posted well in advance on the "Unicode Calendar of Events" web page.


At the discretion of the UTC chair, meetings are open to participation of member and liaison organizations, and to observation by others. The minutes of meetings are also posted publicly on the "UTC Minutes" page of the Unicode Web site.


All UTC meetings are held jointly with the INCITS Technical Committee L2, the body responsible for Character Code standards in the United States. They constitute "ad hoc" meetings of the L2 body and are


usually followed by a full meeting of the L2 committee. Further information on L2 is available on the official INCITS web page.


4. Unicode Technical Committee Procedures
4. Unicode技术委员会程序

The formal procedures of the UTC are publicly available in a document entitled "UTC Procedures", available from the Consortium, and on the Unicode web site.


Despite the invocation of Robert's Rules of Order, UTC meetings are conducted with relative informality in view of the highly technical nature of most discussions. Meetings focus on items from a technical agenda organized and published by the UTC Chair prior to the meeting. Technical items are usually proposals in one of the following categories:


1. Addition of new characters (whole scripts, additions to existing scripts, or other characters)

1. 添加新字符(整个脚本、添加到现有脚本或其他字符)

2. Preparation and Editing of Technical Reports and Standards

2. 编制和编辑技术报告和标准

3. Changes in the semantics of specific characters

3. 特定字符语义的变化

4. Extensions to the encoding architecture and forms of use

4. 编码体系结构和使用形式的扩展

Note: There may also be changes to the architecture, character properties, or semantics. Such changes are rare, and are always constrained by the "Unicode Stability Policies" posted on the Unicode web site. Significant changes are undertaken in consultation with liaison organizations, such as W3C and IETF, which have standards that may be affected by such changes. See sections 5 and 6 below.


Typical outputs of the UTC are:


1. The Unicode Standard, major and minor versions (including the Unicode Character Database)

1. Unicode标准、主要和次要版本(包括Unicode字符数据库)

2. Unicode Technical Reports

2. Unicode技术报告

3. Stand-alone Unicode Technical Standards

3. 独立Unicode技术标准

4. Formal resolutions

4. 正式决议

5. Liaison statements and instructions to the Unicode liaisons to other organizations.

5. 与其他组织联络的Unicode联络声明和指示。

For each technical item on the meeting agenda, the general process is as follows:


1. Introduction by the topic sponsor

1. 专题发起人介绍

2. Proposals and discussion

2. 建议和讨论

3. Consensus statements or formal motions

3. 协商一致声明或正式动议

4. Assignment of formal actions to implement decisions

4. 分配正式行动以执行决策

5. Unicode Technical Committee Motions
5. 技术委员会动议

Technical topics of any complexity never proceed from initial proposal to final ratification or adoption into the standard in the course of one UTC meeting. The UTC members and presiding officers are aware that technical changes to the standard have broad consequences to other standards, implementers, and end-users of the standard. Input from other organizations and experts is often vital to the understanding of various proposals and for successful adoption into the standard.


Technical topics are decided in UTC through the use of formal motions, either taken in meetings, or by means of thirty-day letter ballots. Formal UTC motions are of two types:


1. Simple motions

1. 简单动作

2. Precedents

2. 先例

Simple motions may pass with a simple majority constituting more than 50 percent of the qualified voting members; or by a special majority constituting two-thirds or more of the qualified voting members.


Precedents are defined, according to the UTC Procedures as either


(A) an existing Unicode Policy, or

(A) 现有的Unicode策略,或

(B) an explicit precedent.

(B) 明确的先例。

Precedents must be passed or overturned by a special majority.


Examples of implicit precedents include:


1. Publication of a character in the standard

1. 标准中字符的发布

2. Published normative character properties

2. 已发布的规范性字符属性

3. Algorithms required for formal conformance

3. 形式一致性所需的算法

An Explicit Precedent is a policy, procedure, encoding, algorithm, or other item that is established by a separate motion saying (in effect) that a particular prior motion establishes a precedent.


A proposal may be passed either by a formal motion and vote, or by consensus. If there is broad agreement as to the proposal, and no member wishes to force a vote, then the proposal passes by consensus and is recorded as such in the minutes.


6. Unicode Consortium Policies
6. Unicode联盟策略

Because the Unicode Standard is continually evolving in an attempt to reach the ideal of encoding "all the world's scripts", new characters will constantly be added. In this sense, the standard is unstable: in the standard's useful lifetime, there may never be a final point at which no more characters are added. Realizing this, the Consortium has adopted certain policies to promote and maintain stability of the characters that are already encoded, as well as laying out a Roadmap to future encodings.


The overall policies of the Consortium with regard to encoding stability, as well as other issues such as privacy, are published on a "Unicode Consortium Policies" web page. Deliberations and encoding proposals in the UTC are bound by these policies.


The general effect of the stability policies may be stated in this way: once a character is encoded, it will not be moved or removed and its name will not be changed. Any of those actions has the potential for causing obsolescence of data, and they are not permitted. The canonical combining class and decompositions of characters will not be changed in any way that affects normalization. In this sense, normalization, such as that used for International Domain Naming and "early normalization" for use on the World Wide Web, is fixed and stable for every character at the time that character is encoded. (Any changes that are undertaken because of outright errors in properties or decompositions are dealt with by means of an adjunct data file so that normalization stability can still be maintained by those who need it.)


Once published, each version of the Unicode Standard is absolutely stable and will never be changed retroactively. Implementations or specifications that refer to a specific version of the Unicode Standard can rely upon this stability. If future versions of such implementations or specifications upgrade to a future version of the Unicode Standard, then some changes may be necessary.


Property values of characters, such as directionality for the Unicode Bidi algorithm, may be changed between versions of the standard in some circumstances. As less-well documented characters and scripts are encoded, the exact character properties and behavior may not be well known at the time the characters are first encoded. As more experience is gathered in implementing the newly encoded characters, adjustments in the properties may become necessary. This re-working is kept to a minimum. New and old versions of the relevant property tables are made available on the Consortium's web site.

在某些情况下,字符的属性值(如Unicode Bidi算法的方向性)可能会在标准版本之间更改。由于对文档较少的字符和脚本进行编码,因此在首次对字符进行编码时,可能不知道确切的字符属性和行为。随着在实现新编码字符方面积累更多的经验,可能需要对属性进行调整。这种重新工作保持在最低限度。相关财产表的新版本和旧版本可在联合体的网站上查阅。

Normative and some informative data about characters is kept in the Unicode Character Database (UCD). The structure of many of these property values will not be changed. Instead, when new properties are defined, the Consortium adds new files for these properties, so as not to affect the stability of existing implementations that use the values and properties defined in the existing formats and files. The latest version of the UCD is available on the Consortium web site via the "Unicode Data" heading.


Note on data redistribution: Unlike the situation with IETF documents, some parts of the Unicode Character Database may have restrictions on their verbatim redistribution with source-code products. Users should read the notices in files they intend to use in such products. The information contained in the UCD may be freely used to create derivative works (such as programs, compressed data files, subroutines, data structures, etc.) that may be redistributed freely, but some files may not be redistributable verbatim. Such restrictions on Unicode data files are never meant to prohibit or control the use of the data in products, but only to help ensure that users retrieve the latest official releases of data files when using the data in products.


7. UTC and ISO (WG2)

The character repertoire, names, and general architecture of the Unicode Standard are identical to the parallel international standard ISO/IEC 10646. ISO/IEC 10646 only contains a small fraction of the semantics, properties and implementation guidelines supplied by the Unicode Standard and associated technical standards and reports. Implementations conformant to Unicode are conformant to ISO/IEC 10646.

Unicode标准的字符表、名称和通用体系结构与并行国际标准ISO/IEC 10646相同。ISO/IEC 10646仅包含Unicode标准及相关技术标准和报告提供的语义、属性和实施指南的一小部分。符合Unicode的实现符合ISO/IEC 10646。

ISO/IEC 10646 is maintained by the committee ISO/IEC JTC1/SC2/WG2. The WG2 committee is composed of national body representatives to ISO. Details on the ISO organization may be found on the official web site of the International Organization for Standardization (ISO).

ISO/IEC 10646由ISO/IEC JTC1/SC2/WG2委员会维护。WG2委员会由ISO的国家机构代表组成。有关ISO组织的详细信息,请访问国际标准化组织(ISO)的官方网站。

Details and history of the relationship between ISO/IEC JTC1/SC2/WG2 and Unicode, Inc. may be found in Appendix C of The Unicode Standard. (A PDF rendition of the most recent printed edition of the Unicode Standard can be found on the Unicode web site.)

有关ISO/IEC JTC1/SC2/WG2与Unicode,Inc.之间关系的详细信息和历史记录,请参见Unicode标准的附录C。(Unicode网站上提供了Unicode标准最新印刷版的PDF格式副本。)

WG2 shares with UTC the policies regarding stability: WG2 neither removes characters nor changes their names once published. Changes in both standards are closely tracked by the respective committees, and a very close working relationship is fostered to maintain synchronization between the standards.


The Unicode Collation Algorithm (UCA) is one of a small set of other independent standards defined and maintained by UTC. It is not, properly speaking, part of the Unicode Standard itself, but is separately defined in Unicode Technical Standard #10 (UTS #10). There is no conformance relationship between the two standards, except that conformance to a specific base version of the Unicode Standard (e.g., 4.0) is specified in a particular version of a UTS. The collation algorithm specified in UTS #10 is conformant to ISO/IEC 14651, maintained by ISO/IEC JTC1/SC2, and the two organizations maintain a close relationship. Beyond what is specified in ISO/IEC 14651, the UCA contains additional constraints on collation, specifies additional options, and provides many more implementation guidelines.

Unicode排序算法(UCA)是UTC定义和维护的一小部分其他独立标准之一。正确地说,它不是Unicode标准本身的一部分,而是在Unicode技术标准10(UTS 10)中单独定义的。这两个标准之间没有一致性关系,除非在UTS的特定版本中指定了与Unicode标准的特定基本版本(例如4.0)的一致性。UTS#10中规定的排序算法符合ISO/IEC 14651,由ISO/IEC JTC1/SC2维护,两个组织保持着密切的关系。除了ISO/IEC 14651中规定的内容之外,UCA还包含关于排序的附加约束,指定了附加选项,并提供了更多的实施指南。

8. Process of Technical Changes to the Unicode Standard
8. Unicode标准的技术更改过程

Changes to The Unicode Standard are of two types: architectural changes, and character additions.


Most architectural changes do not affect ISO/IEC 10646, for example, the addition of various character properties to Unicode. Those architectural changes that do affect both standards, such as additional UTF formats or allocation of planes, are very carefully coordinated by the committees. As always, on the UTC side, architectural changes that establish precedents are carefully monitored and the above-described rules and procedures are followed.

大多数架构更改不会影响ISO/IEC 10646,例如,在Unicode中添加各种字符属性。那些确实影响这两个标准的架构变更,例如额外的UTF格式或飞机分配,由委员会非常仔细地协调。与往常一样,在UTC方面,对建立先例的架构更改进行仔细监控,并遵循上述规则和程序。

Additional characters for inclusion in the The Unicode Standard must be approved both by the UTC and by WG2. Proposals for additional characters enter the standards process in one of several ways: through...


1. a national body member of WG2

1. WG2的国家机构成员

2. a member company or associate of UTC

2. UTC的成员公司或合伙人

3. directly from an individual "expert" contributor

3. 直接来自个人“专家”贡献者

The two committees have jointly produced a "Proposal Summary Form" that is required to accompany all additional character proposals. This form may be found online at the WG2 web site, and on the Unicode web site along with information about "Submitting New Characters or Scripts". Instructions for submitting proposals to UTC may likewise be found online.


Often, submission of proposals to both committees (UTC and WG2) is simultaneous. Members of UTC also frequently forward to WG2 proposals that have been initially reviewed by UTC.


In general, a proposal that is submitted to UTC before being submitted to WG2 passes through several stages:


1. Initial presentation to UTC

1. 向UTC的初始演示

2. Review and re-drafting

2. 审查和重新起草

3. Forwarding to WG2 for consideration

3. 转交第二工作组审议

4. Re-drafting for technical changes

4. 技术变更的重新起草

5. Balloting for approval in UTC

5. UTC中的投票批准

6. Re-forwarding and recommendation to WG2

6. 向第二工作组转发和推荐

7. At least two rounds of international balloting in ISO

7. 国际标准化组织至少两轮国际投票

About two years are required to complete this process. Initial proposals most often do not include sufficient information or justification to be approved. These are returned to the submitters with comments on how the proposal needs to be amended or extended. Repertoire addition proposals that are submitted to WG2 before being submitted to UTC are generally forwarded immediately to UTC through committee liaisons. The crucial parts of the process (steps 5 through 7 above) are never short-circuited. A two-thirds majority in UTC is required for approval at step 5.


Proposals for additional scripts are required to be coordinated with relevant user communities. Often there are ad-hoc subcommittees of UTC or expert mail list participants who are responsible for actually drafting proposals, garnering community support, or representing user communities.


The rounds of international balloting in step 7 have participation both by UTC and WG2, though UTC does not directly vote in the ISO process.


Occasionally a proposal approved by one body is considered too immature for approval by the other body, and may be blocked de-facto by either of the two. Only after both bodies have approved the additional characters do they proceed to the rounds of international balloting. (The first round is a draft international standard during which some changes may occur, the second round is final approval during which only editorial changes are made.)


This process assures that proposals for additional characters are mature and stable by the time they appear in a final international ballot.


9. Public Access to the Character Encoding Process
9. 公开访问字符编码过程

While Unicode, Inc. is a membership organization, and the final say in technical matters rests with UTC, the process is quite open to public input and scrutiny of processes and proposals. There are many influential individual experts and industry groups who are not formally members, but whose input to the process is taken seriously by UTC.


Internally, UTC maintains a mail list called the "Unicore" list, which carries traffic related to meetings, technical content of the standard, and so forth. Members of the list are UTC representatives; employees and staff of member organizations (such as the Research Libraries Group); individual liaisons to and from other standards bodies (such as WG2 and IETF); and invited experts from institutions such as the Library of Congress and some universities. Subscription to the list for external individuals is subject to "sponsorship" by the corporate officers.


Unicode, Inc. also maintains a public discussion list called the "Unicode" list. Subscription is open to anyone, and proceedings of the "Unicode" mail list are publicly archived. Details are on the Consortium web site under the "Mail Lists" heading.


Technical proposals for changes to the standard are posted to both of these mail lists on a regular basis. Discussion on the public list may result in a written proposal being generated for a later UTC meeting. Technical issues and other standardization "events" of any significance, such as beta releases and availability of draft documents, are announced and then discussed in this public forum, well before standardization is finalized. From time to time, the UTC also publishes on the Consortium web site "Public Review Issues" to gather feedback and generate discussion of specific proposals whose impact may be unclear, or for which sufficiently broad review may not yet have been brought to the UTC deliberations.


Anyone may make a character encoding or architectural proposal to UTC. Membership in the organization is not required to submit a proposal. To be taken seriously, the proposal must be framed in a substantial way, and be accompanied by sufficient documentation to warrant discussion. Examples of proposals are easily available by following links from the "Proposed Characters" and "Roadmaps" headings on the Unicode web site. Guidelines for proposals are also available under the heading "Submitting Proposals".


In general, proposals are publicly aired on the "Unicode" mail list, sometimes for a long period, prior to formal submission. Generally this is of benefit to the proposer as it tends to reduce the number of times the proposal is sent back for clarification or with requests for additional information. Once a proposal reaches the stage of being ready for discussion by UTC, the proposer will have received contact through the public mail list with one or more UTC members willing to explain or defend it in a UTC meeting.


10. Acknowledgements
10. 致谢

Thanks to Mark Davis, Simon Josefsson, and Ken Whistler for their extensive review and feedback on previous versions of this document.

感谢Mark Davis、Simon Josefsson和Ken Whistler对本文档以前版本的广泛审查和反馈。

11. Security Considerations
11. 安全考虑

This memo describes the operational procedures of an organization; the procedures themselves have no consequences for Internet Security.


12. Author's Address
12. 作者地址

Rick McGowan c/o The Unicode Consortium P.O. Box 391476 Mountain View, CA 94039-1476 U.S.A.

Rick McGowan转交美国加利福尼亚州山景城Unicode财团邮政信箱391476,邮编94039-1476。

   Phone:   +1-650-693-3921
   Phone:   +1-650-693-3921
13. Full Copyright Statement
13. 完整版权声明

Copyright (C) The Internet Society (2004). This document is subject to the rights, licenses and restrictions contained in BCP 78 and except as set forth therein, the authors retain all their rights.

版权所有(C)互联网协会(2004年)。本文件受BCP 78中包含的权利、许可和限制的约束,除其中规定外,作者保留其所有权利。



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