Following the ICANN Board's acceptance at the October 2011 meeting in Dakar, Senegal, ICANN is today providing notice of implementation for version 3.0 of the Guidelines for Implementation of Internationalized Domain Names. The IDN Guidelines are a list of general standards that many top-level domain registries deploying IDNs are required to follow based on the Internationalized Domain Names for Applications (IDNA) protocol standard from the IETF.
The Guidelines document was developed by IDN Guidelines Revision Working Group (comprised of ccTLD and gTLD registry representatives with IDN experience supported by ICANN staff). The new version modifies the current Version 2.2 to reflect the IDNABIS revision ("IDNA2008 protocol") of the initial IDNA protocol ("IDNA2003"). ICANN previously published a draft version of the guidelines for public comment (see http://www.icann.org/en/public-comment/idn-guidelines-revision-27jul11-en.htm). The ICANN Board of Directors endorsed version 3.0 of the IDN Guidelines during their meeting on 28 October 2011. Registries offering IDN registrations should begin transitioning to version 3.0 of the IDN Guidelines.
The Internationalized Domain Names for Applications (IDNA) protocol is the technical standard for the implementation of IDNs for TLD registries, registrars and software developers that make IDNs available for their customers. The IDNA protocol references and further detail about the 2008 revision can be found here: http://www.icann.org/en/topics/idn/rfcs.htm