Re: [idn] case folding and Vietnamese

[Maurizio Codogno <mau@beatles.cselt.it>]

> From: RJ Atkinson <rja@inet.org>

> One could imagine a URL:
> 
>          http://www.d-o^ng.vn
> 
> and its capitalised equal:
> 
>          http://WWW.D-O^NG.VN
> 
> It would be broken for users if those two URLs above did not 
> go to the same web page.  If we only case-map [a-z, A-Z], 
> then we would not case-map "d-" with "D-" or case-map "o^" 
> with "O^", thus making the 2 fictional URLs above map to 
> different web pages.  

But the problem is that since the beginning they should have ]
considered d-o^ng and D-O^NG different labels! 
We cannot do this for ASCII roman letters [A-Za-z], since we must
retain backward compatibility, but nobody can stop us from saying
"if in a label there is a character outside [0-9A-Za-z-], then
that label is case sensitive".

This formulation has the advantage that .VN and .vn are the same 
label :-)

This said, I have no problem in accepting UTR#21, providing that 
it is consistent .

ciao, .mau.