Maximal Starting Repertoire Version 4 (MSR-4) Released

7 February 2019

LOS ANGELES – 7 February 2019 - The Internet Corporation for Assigned Names and Numbers (lCANN) today announced the release of the fourth version of the Maximal Starting Repertoire (MSR-4). This version is upwardly compatible with MSR-3 and adds three code points to the repertoire of Latin script and 12 code points to the repertoire of Myanmar script. Under the Procedure to Develop and Maintain Label Generation Rules for the Root Zone with Respect to IDN Labels [PDF, 771 KB], the MSR is the starting point for the work by community-based Generation Panels developing the Root Zone Label Generation Rules (RZ-LGR) proposals for relevant scripts.

The contents of MSR-4 and the detailed rationale behind its development are described in the MSR-4 Overview and Rationale [PDF, 800 KB] document. MSR-4 covers 28 scripts: Arabic, Armenian, Bengali, Cyrillic, Devanagari, Ethiopic, Georgian, Greek, Gujarati, Gurmukhi, Han, Hangul, Hebrew, Hiragana, Kannada, Katakana, Khmer, Lao, Latin, Malayalam, Myanmar, Oriya, Sinhala, Tamil, Telugu, Thaana, Tibetan and Thai. For these scripts, MSR-4 contains 33,511 code points short-listed from 97,973 PVALID/CONTEXT code points of Unicode version 6.3.

MSR-4 defers code points that are already encoded in later releases of Unicode and will make these available after their reference tables for IDNA 2008 are published. In addition, the Integration Panel monitors any scripts not included in the MSR for indications that change in MSR is warranted. Until such a change of the MSR, MSR-4 will be the foundation for any RZ-LGR versions developed. All future versions of the MSR and all versions of the RZ-LGR must retain full backwards compatibility.


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