National and Local Characters for DNS Top Level Domain (TLD) Names
RFC 4185
Document | Type |
RFC - Informational
(October 2005; No errata)
Was draft-klensin-idn-tld (int)
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Author | John Klensin | ||
Last updated | 2015-10-14 | ||
Stream | Independent Submission | ||
Formats | plain text html pdf htmlized (tools) htmlized bibtex | ||
Stream | ISE state | (None) | |
Consensus Boilerplate | Unknown | ||
Document shepherd | No shepherd assigned | ||
IESG | IESG state | RFC 4185 (Informational) | |
Action Holders |
(None)
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Telechat date | |||
Responsible AD | Margaret Cullen | ||
Send notices to | (None) |
Network Working Group J. Klensin Request for Comments: 4185 October 2005 Category: Informational National and Local Characters for DNS Top Level Domain (TLD) Names 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 (2005). IESG Note This RFC is not a candidate for any level of Internet Standard. The IETF disclaims any knowledge of the fitness of this RFC for any purpose and notes that the decision to publish is not based on IETF review apart from IESG review for conflict with IETF work. The RFC Editor has chosen to publish this document at its discretion. See RFC 3932 [RFC3932] for more information. Abstract In the context of work on internationalizing the Domain Name System (DNS), there have been extensive discussions about "multilingual" or "internationalized" top level domain names (TLDs), especially for countries whose predominant language is not written in a Roman-based script. This document reviews some of the motivations for such domains, several suggestions that have been made to provide needed functionality, and the constraints that the DNS imposes. It then suggests an alternative, local translation, that may solve a superset of the problem while avoiding protocol changes, serious deployment delays, and other difficulties. The suggestion utilizes a localization technique in applications to permit any TLD to be accessed using the vocabulary and characters of any language. It is not restricted to language- or country-specific "multilingual" TLDs in the language(s) and script(s) of that country. Klensin Informational [Page 1] RFC 4185 Characters for DNS TLD Names October 2005 Table of Contents 1. Introduction ....................................................3 1.1. Terminology ................................................3 1.2. Background on the "Multilingual Name" Problem ..............3 1.2.1. Approaches to the Requirement .......................3 1.2.2. Writing the Name of One's Country in its Own Characters ..........................................4 1.2.3. Countries with Multiple Languages and Countries with Multiple .............................5 1.2.4. Availability of Non-ASCII Characters in Programs ....5 1.3. Domain Name System Constraints .............................6 1.3.1. Administrative Hierarchy ............................6 1.3.2. Aliases .............................................6 1.4. Internationalization and Localization ......................7 2. Client-Side Solutions ...........................................7 2.1. IDNA and the Client ........................................8 2.2. Local Translation Tables for TLD Names .....................8 3. Advantages and Disadvantages of Local Translation ...............9 3.1. Every TLD Appears in the Local Language and Character Set ..9 3.2. Unification of Country Code Domains .......................10 3.3. User Understanding of Local and Global References .........11 3.4. Limits on Expansion of the Number of TLDs .................11 3.5. Standardization of the Translations .......................12 3.6. Implications for Future New Domain Names ..................13 3.7. Mapping for TLDs, Not Domain Names or Keywords ............13 4. Information Interchange, IDNs, Comparisons, and Translations ...13 5. Internationalization Considerations ............................15 6. Security Considerations ........................................15 7. Acknowledgements ...............................................16 8. Informative References .........................................17 Klensin Informational [Page 2] RFC 4185 Characters for DNS TLD Names October 2005 1. Introduction 1.1. Terminology This document assumes the conventional terminology used to discuss the domain name system (DNS) and its hierarchical arrangements. Terms such as "top level domain" (or just "TLD"), "subdomain", "subtree", and "zone file" are used without further explanation. In addition, the term "ccTLD" is used to denote a "country code top level domain" and "gTLD" is used to denote a "generic top level domain" as described in [RFC1591] and in common usage. 1.2. Background on the "Multilingual Name" Problem People who share a language usually prefer to communicate in it, using whatever characters are normally used to write that language,Show full document text