Re: [idn] UTF-8 / RACE

[Alan Barrett <apb@cequrux.com>]

On Mon, 28 May 2001, James Seng/Personal wrote:
> Aside, I am a bit confuse by your defination of "UTF-8 with Fast
> Nameprep". When you mean "Fast Nameprep", do you mean we don't do
> Nameprep at all?

Dan Bernstein's "fast nameprep" means "early nameprep", where nameprep
happens once, as early as possible when the user types a domain name,
and everything outside the keyboard interface can assume that nameprep
has already been done.  Dan's "slow nameprep" means "late nameprep",
where just about anything that wants to do an IDN lookup needs to do
nameprep.

I don't believe that doing early nameprep removes the need for late
nameprep, because any number of intermediate transformations
(involving different encodings of UCS, different normalisations, or
even completely different character sets) might have happened between
the keyboard and the lookup.

--apb (Alan Barrett)