any DNS zone administration is described as a "registry", and the terms "registry" and "zone administrator" are used interchangeably, regardless of the actual administrative arrangements or level in the DNS tree.
As with other documents in the IDNA2008 set, this document uses the term "registry" to describe any zone in the DNS. That term, and the terms "zone" or "zone administration", are interchangeable.
[7] Windowsレジストリーとは無関係です。