Re: Re: Standardizing on IDNA 2003 in the URL Standard

On Thu, Jan 16, 2014 at 10:07:36AM +0800, Jiankang Yao wrote:
> 
>   In which section of rfc idnabis does say some meaning related to  that " "Aà.com" is not PVALID"?

Upper case characters are not PVALID.  This is because of B:
toNFKC(toCaseFold(toNFKC(cp))) != cp.  In appendix B.1 it's
illustrated in this entry:

003A..0060  ; DISALLOWED  # COLON..GRAVE ACCENT
 
> I check Aà.com in verisign conversion tool, it shows "xn--a-sfa.com"
> 
> http://mct.verisign-grs.com/convertServlet?input=A%C3%A0.com 
> 
> does it follow idna2003 instead of idnabis?

I have no idea.  Maybe it has a bug.  Or maybe it does case mapping
before it touches the string; that's what RFC 5895 suggests.  In that
case, of course, the Verisign conversion tool includes some things
that applications are supposed to do.

A

-- 
Andrew Sullivan
ajs@anvilwalrusden.com