The specification provides two main features for use with the new specification for internationalized domain names released in August 2010 (IDNA2008):
1. A comprehensive mapping to reflect user expectations for casing and other variants of domain names. This mapping is allowed by IDNA2008, and follows the same principles as in the previous version of that specification (IDNA2003, in force from 2003 until August). It thus provides users consistency between old and new versions.
2. A compatibility mechanism that supports internationalized domain names valid under the IDNA2003 specification and the IDNA2008 specification. This second feature allows browsers, search engines, and other clients to handle both old and new domain names during the transitional period until registries update their rules to follow IDNA2008.
UTS #46 supplies normative data tables that are synchonized with the latest version of Unicode, allowing implementations to update without recalculation.
This new release of UTS #46 also provides a custom option to recognize legacy international domain names containing special ASCII characters such as "_".
About The Unicode Consortium
The Unicode Consortium is a non-profit organization founded to develop, extend and promote use of the Unicode Standard and related globalization standards. The membership of the consortium represents a broad spectrum of corporations and organizations in the computer and information processing industry.
Members are: Adobe, Apple, Google, Government of Bangladesh, Government of India, IBM, Microsoft, Monotype Imaging, Oracle, The Society for Natural Language Technology Research, SAP, The University of California (Berkeley), The University of California (Santa Cruz), Yahoo!, plus well over a hundred Associate, Liaison, and Individual members.
For more information, please contact the Unicode Consortium. http://www.unicode.org/contacts.html