Hi. There's some good info online. https://www.icann.org/resources/pages/approved-with-specs-2013-09-17-en https://www.icann.org/resources/pages/approved-with

Hi. There's some good info online. https://www.icann.org/resources/pages/approved-with-specs-2013-09-17-en https://www.icann.org/resources/pages/approved-with-specs-20... Check out section 3.3.6