UTS #46, Unicode IDNA Compatibility Processing, Version 6.1 Released

Mountain View, CA, USA – February 1, 2010 – The new version of Unicode Technical Standard #46, Unicode IDNA Compatibility Processing has been released, updating to Unicode Version 6.1. It adds support for 528 additional characters in internationalized domain names (IDN).
The specification provides two main features for use with the internationalized domain names specification 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). 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 synchronized with the latest version of the Unicode Standard, allowing implementations to update without recalculation. This new version also provides an "NV8" flag in the data files, making it easier for implementations to disable the compatibility mechanism.