Re: [idn] nameprep (Korean Nameprep)

["Mark Davis" <markdavis34@home.com>]

1. It is correct that neither the compatibility Jamo nor the half-width Jamo
are combined into Hangul syllables by the normalization algorithm. However,
those Jamo are not intented for use in constructing Hangul syllables --
instead, the conjoining Jamo are. And those are correctly composed into
syllables, if individual Jamo are input.

It would be possible to deal separately with those characters in nameprep --
although without more information it is not possible to completely eliminate
ambiguity in choosing whether a consonant is leading or trailing. Do you
believe this is, in practice, a really problem; that there are a large
number of people that produce Korean text with compatibility or half-width
Jamo, instead of Hangul syllables?

2. I don't have a strong position (nor do I think the Unicode Consortium
would) on the issue of whether to disallow the filler characters. They are
not required for correct representation of Korean, and could be either
prohibited or filtered out.

3. As to the issue of visual ambiguity, that is already present across other
scripts. Greek O, Latin O, and Cyrillic O are identical. The problem is that
the amount of allowable variation between acceptable glyphs for given
characters in different scripts (or symbols and punctuation!) is not easy to
quantify, nor is there any clear-cut data upon which to draw in this area.
This topic has arisen before, and I believe the consensus is to leave
matters as they are.

Mark

----- Original Message -----
From: "Soobok Lee" <lsb@postel.co.kr>
To: "Adam M. Costello" <amc@cs.berkeley.edu>; <idn@ops.ietf.org>; "Paul
Hoffman / IMC" <phoffman@imc.org>
Sent: Thursday, May 31, 2001 21:39
Subject: Re: [idn] nameprep (Korean Nameprep)


> We (KRNIC NC) found a KC normalization implementation
> in nameprep-03 does not preserve
> the hangul compatibility jamo character sequences,
> but combines them into hangul syllables with errornously leaving
> jongseong jamo behind (CVL -> (CV)(L) [false],  (CVL) is right).
>
> I think we may consider taking away this hangul combining actions
> from nameprep-implementation of KC normalization.
>
> and more work should be done on whether to prohibit
> the 4 hangul filler characters,
> and on case-folding of hangul jamo characters in 4 forms
> (choseong,jongseong,compatibility jamo,narrow-form).
>
> we are studying the ambiguity  that may arise between hangul and
> many other language character sets. Japanese katakana 'ro' and
> hangul jamo 'mieum' look the same!
> If multilingual names are introduced in ML@ML.com, http://ML.com,
> this ambiguity issues become the internet security issues, i am afraid.
>
> We'll continue to follow up IDN wg's nameprep efforts and submit a
> draft if necessary.
>
> Soobok Lee
> lsb@postel.co.kr
>
> ----- Original Message -----
> From: "Paul Hoffman / IMC" <phoffman@imc.org>
> To: "Adam M. Costello" <amc@cs.berkeley.edu>; <idn@ops.ietf.org>
> Sent: Friday, June 01, 2001 12:38 PM
> Subject: Re: [idn] nameprep
>
>
> > At 3:07 AM +0000 6/1/01, Adam M. Costello wrote:
> > >Paul Hoffman / IMC <phoffman@imc.org> wrote:
> > >
> > >>  need to finish nameprep, which at this point is finished other than
it
> > >>  does not address the new characters added in Unicode 3.1.
> > >
> > >Nameprep currently includes the following steps:
> > >
> > >     KC-normalize
> > >     map
> > >     KC-normalize
> > >     prohibit
> >
> > Er, no it doesn't. It only includes map->normalize->prohibit.
> >
> > --Paul Hoffman, Director
> > --Internet Mail Consortium
> >
>
>