コ andム  are katakana characters, so only examples 1 and 3 are valid from a language perspective.   Those characters do not exist within hiragana and I do not believe they exist as standalone Chinese characters, either.

From: UA-discuss <ua-discuss-bounces@icann.org> On Behalf Of Jim DeLaHunt
Sent: Sunday, February 25, 2018 2:13 PM
To: ua-discuss@icann.org
Subject: Re: [UA-discuss] IANA IDN Tables

Thank you! I had not known about the IANA IDN tables, and they are fascinating reading.

In particular, it provides a concrete way of talking about registry policies that affect phishing attacks through confusables, as discussed in our "Another difficulty to overcome ..." thread a few days ago.

     —Jim DeLaHunt, Vancouver, Canada

On 2018-02-25 03:54, Andre Schappo wrote:

It must be over a year since I last looked at the IANA IDN tables and they have grown massively in that time ➜ iana.org/domains/idn-tables

Some observations: I will use Verisignʼs Japanese .コム (transliteration of .com)

There is .コム Japanese, which is LDH (ASCII Letters, Digits, Hyphen) + Hiragana + Katakana + a heap of Han

There is .コム Hiragana, which is DH + Hiragana

There is .コム Katakana, which is DH + Katakana

There is .コム Han, which is DH + a heap of Han

André Schappo

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