Subject: Re: [idn] spoofing by combining diacritical marks

From: "James Seng/Personal" <[email-masked]>
Date: Thu, 30 Aug 2001 14:40:19 +0800

Sorry didnt finish the last statement.

I disagree not because I do not think optional filtering is good. I
disagree about making filtering as part of Nameprep standard, especially
one which is optional.

If KRNIC decides that it will do filtering on its zone and registrations
only to accept hanguel characters and not any han ideographs and
european scripts, then it is KRNIC choice. Likewise, other NICs may
decide what is valid or not valid. However, this is a policy decision of
any particular NICs and should not be defined in any standard.

Nameprep is to do preparation of names for names matching, not to impose
filterings rules some NICs thinks it is useful to have.

-James Seng

> > "Postpone" cannot be put into nameprep, mechanical filtering.
clear.
> > "Guidelines for zone-masters", optional human filtering in
> registration phase,
> >  is the only feasible choice in this case.
>
> I disagree. What makes you sure that there wouldn't be a valid reason
to
> use a double or triple accute?
>
> -James Seng
>

---

From: "Soobok Lee" <[email-masked]>
Date: Thu, 30 Aug 2001 15:57:27 +0900

----- Original Message ----- 
From: "Soobok Lee" <[email-masked]>
 > 
> BTW, Unicode Standard Chap2. Section 2.6, Figure 2-10 has an example:
> 
>   <latin a><combining dot below><combining dot above>
>   <latin a><combining dot above><combining dot below>
> 
>  These two sequences are defined to have the same look
>  But, I can't find yet any _NORMALIZATION_ rules to unify them.
> 
>  Does unicode standards have any rules to unify them  ?

Let me answer for myself. :-)

Yes.   UTR15 (unicode normalization)
 http://www.unicode.org/unicode/reports/tr15/

describes the concept of canonical ordering  and combining class 
of combining characters.

The two sequences in the example are normalized into one in NFC/NFKC.

Great!

>  Soobok

---

From: Eric Brunner <[email-masked]>
Date: Thu, 30 Aug 2001 13:32:46 -0400

> Is anyone working on such a document?
> 
> On Thu, 30 Aug 2001, James Seng/Personal wrote:
> 
> > What you are looking for is a Best Current Practice draft for operation
> > of IDN. Currently there is none so my best suggestion is to write a new
> > I-D on this.

The subject has come up on a gtldc (ICANN) list. The proposant assumed that
a standard was sufficient, universal, easy, and RSN, and that cc and g rules
were or would be harmonized. Last time I checked there were 267 TLDs in the
root, and a _larger_ number of delegated zones ...

Please see the discussion of scope, "[30]", earlier in this list.

Eric

---

From: Eric Brunner <[email-masked]>
Date: Thu, 30 Aug 2001 13:41:13 -0400

> patched one, allowing <acute><acute> in IDN label  should be postponed
> for security reasons.

Several North American languages use two or more diacriticals. Penobscot
uses as many as four on a single "character", as in (visualize as stacked )

	e''''

E''''ric