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Universal Acceptance

Get Involved
Frequently Asked Questions
Useful Links


24 March 2015 – Universal Acceptance Steering Group Publishes Charter

The Universal Acceptance Steering Group Charter is now available for review. Learn about the UASG's mission, scope, goals and more.

10 February 2015 – Universal Acceptance Initiative Ramps Up at ICANN 52

Photo of Christian Dawson addressing ICANN Board during Public Forum

Christian Dawson addresses the ICANN Board: "The ICANN community should support the creation of a steering group to guide the identification of top line issues and propose solutions, as well as the creation and dissemination of best practices and general outreach information about Universal Acceptance."


In the earliest days of the Internet, the Domain Name System (DNS) contained a small set of Top-Level Domains (TLDs), such as .com, .net and .org, which were named in the ASCII character set containing two or three A-Z letters. Early applications and service user interfaces were based on these assumptions remaining the same, and worked to help and protect Internet users by allowing only "known" TLDs to be used.

Universal Acceptance refers to the occurrence of users experiencing browser and email bugs when trying to use new gTLDs. Operators of new gTLDs and more visibly all IDN TLDs (gTLDs and ccTLDs) are seeing unnaturally limited demand for names in the zones and this has presented a challenge to the goals of the new gTLD program of user choice, user confidence and name space competition.

Domain names in a TLD must be useable in applications regardless of the written script, length or newness of the TLD. The four main shifts spurring the need for Universal Acceptance:

  1. Longer TLD Names: TLDs with names longer than four characters, such as MUSEUM.

  2. Non-Latin based TLDs: Resulting from the addition of TLD names written in scripts other than ASCII, such as Cyrillic, Arabic and Chinese.

  3. Rapid addition of TLDs: The New gTLD Program is spurring very rapid additions of long ASCII names and IDN names – as of 15 August 2014, there were 1,326 applications currently proceeding through the New gTLD Program.

  4. International Email: The introduction of non-ASCII names in email. While International Domain Names (IDNs) solved part of the ability to have non-ASCII names for servers, it doesn't solve the ability to have non-ASCII names for mailboxes.

As the Internet evolved to be more personal, targeted and global, these assumptions are no longer valid. But limitations based on the old assumptions linger and now are preventing a larger and ever growing group of users from accessing the entire expanse of the Internet. In some instances, Internet users trying to use the newly delegated generic Top Level Domain (gTLDs), whose names may be many characters long and/or in non-Latin scripts, can experience "bugs" or the inability to access/register the sites.

This problem must be solved, and Universal Acceptance realized, in order to achieve a truly global, scalable Internet. It will be considered complete when any person can register and use a domain name in any top-level domain in widely distributed web browsers, email clients, in setting up accounts for Internet services and other services. To submit questions or contribute additional material that may be helpful in overcoming these barriers, please email to:

Read Frequently Asked Questions


ICANN has established a roadmap charting its involvement in achieving Universal Acceptance, see the Universal Acceptance Initiative Roadmap.


Get Involved: Help Achieve Universal Acceptance

To submit questions or contribute additional material that may be helpful in further work on this, please email to:

Please visit the Universal Acceptance community wiki:


Background: How did we get where we are today?

Universal Acceptance Timeline

Pre 2000

  • Introduction of "com/net/org" and the ISO 3166 two letter codes
  • Introduction of email addresses (mailbox names) were ASCII
  • Assumptions were made, "burned in". User interfaces would list valid TLDs and security rules were built according to this list.


  • Expansion approved in 2000 and again in 2003 Broke assumptions about Valid TLDs re: name length (already have these dates, obviously)
  • Expansion into IDN ccTLDs, broke assumptions re: ASCII in TLD names
  • Hundreds of New gTLDs proposed, Broke assumptions of "no/few changes" to root
  • Email names extended from ASCII to UTF8, Broke assumptions in email systems and viewers


  • The first IDN ccTLDs appeared in May 2010.
  • The delegations of the 2012 round of so-called new gTLDs started in Fall (October) 2013 and continues, they were "proposed" in 2012. (You know the story.) But refrain from being very specific; keep this info graphic as a cartoon, so as not to drawn attention to the fuzziness of the history.
  • Email addresses in Unicode


Frequently Asked Questions

Get the details on Universal Acceptance. Read Frequently Asked Questions »


Useful Links to Universal Acceptance Materials

Sessions and Presentations at ICANN Meetings

ICANN 51 Universal Acceptance Session Archive  
ICANN 50 Universal Acceptance Session Archive ISPCP Session Slides [PDF, 1.05 MB]
ICANN 49 TLD Universal Acceptance Session Archive  
ICANN 45 Universal Acceptance of All TLDs Slides [PDF, 1.07 MB]  
ICANN 44 Universal Acceptance of All TLDs Slides [PDF, 1.23 MB]  
ICANN 43 Universal Acceptance of All TLDs Slides [PDF, 1.28 MB]  

Universal Acceptance Initiative Roadmap

2014 September Roadmap
2014 August Summary Report of Public Comment on Draft Roadmap [PDF, 377 KB]
2014 June Public Comment on Draft Roadmap opened

ICANN Presentations at other events

Date Event Title/Agenda ICANN Slides
2014 October APEC EAI Workshop ICANN Slides [PDF, 805 KB]
2014 June CENTR Jamboree 2014 ICANN Slides [PDF, 685 KB]
2014 May APTLD Member Meeting on Universal Acceptance ICANN Slides [PDF, 678 KB]
2014 February APRICOT 2014 ICANN Slides [PDF, 3.20 MB]
2012 October Internationalization and Unicode Conference 36 ICANN Slides [PDF, 2.82 MB]
2012 June JIG IDN WG Meeting ICANN Slides [PDF, 1.11 MB]
2012 May Registry/Registrar Meeting 2012 ICANN Slides [PDF, 4.03 MB]

Other ICANN Material

Continually Updated IANA List of Top-Level Domains
Continually Updated IANA Reports on TLD (Re-) Assignments
2014 March ICANN Blog Entry
2013 June JIG IDN WG Draft Final Report Announcement
2012 January Public Comment: Initial Report on Universal Acceptance of IDN TLDs
2007 March ICANN Releases Beta-3 Version of TLD Verification Code
2006 December ICANN Releases Beta TLD Verification Tool
2006 March ICANN Creates Area on Universal Acceptance of TLDs
2004 December TLD-Acceptance Discussion Forum
2004 October Universal Acceptance of all gTLD Names
2001 July ICP-3: A Unique, Authoritative Root for the DNS
2001 July Keeping the Internet A Reliable Global Public Resource

Non-ICANN Resources

All of these links are external, offered as references only

Date Source Link
2014 CTIC IDN Assessment Report 2014 [PDF, 1.01 MB]
2014 CITC Assessment of IDNA user experience [PDF, 4.62 MB]
2014 EurID World report on IDNs 2014 [PDF, 6.19 MB]
2014 March W3C W3C Mail thread on TLD Universal Acceptance
2014 February CircleID CircleID Post on TLD operator "use case"
2013 EURid World Report on IDN Deployment 2013 [PDF, 3.09 MB]
2012 EURid-UNESCO World report on IDN deployment 2012 [PDF, 4.09 MB]
2004 February IETF RFC 3696: Checking and Transformation of Names
2002 October Internic Why Universal Resolvability is Important


Domain Name System
Internationalized Domain Name ,IDN,"IDNs are domain names that include characters used in the local representation of languages that are not written with the twenty-six letters of the basic Latin alphabet ""a-z"". An IDN can contain Latin letters with diacritical marks, as required by many European languages, or may consist of characters from non-Latin scripts such as Arabic or Chinese. Many languages also use other types of digits than the European ""0-9"". The basic Latin alphabet together with the European-Arabic digits are, for the purpose of domain names, termed ""ASCII characters"" (ASCII = American Standard Code for Information Interchange). These are also included in the broader range of ""Unicode characters"" that provides the basis for IDNs. The ""hostname rule"" requires that all domain names of the type under consideration here are stored in the DNS using only the ASCII characters listed above, with the one further addition of the hyphen ""-"". The Unicode form of an IDN therefore requires special encoding before it is entered into the DNS. The following terminology is used when distinguishing between these forms: A domain name consists of a series of ""labels"" (separated by ""dots""). The ASCII form of an IDN label is termed an ""A-label"". All operations defined in the DNS protocol use A-labels exclusively. The Unicode form, which a user expects to be displayed, is termed a ""U-label"". The difference may be illustrated with the Hindi word for ""test"" — परीका — appearing here as a U-label would (in the Devanagari script). A special form of ""ASCII compatible encoding"" (abbreviated ACE) is applied to this to produce the corresponding A-label: xn--11b5bs1di. A domain name that only includes ASCII letters, digits, and hyphens is termed an ""LDH label"". Although the definitions of A-labels and LDH-labels overlap, a name consisting exclusively of LDH labels, such as"""" is not an IDN."