Re: [idn] time to move

["Adam M. Costello" <amc@cs.berkeley.edu>]

Dan <Dan.Oscarsson@trab.se> wrote:

> If we decide that DNS should use UTF-8 and ACE is a transition
> mechanism...

Please remember that DNS is not the problem.  DNS is just one of many
protocols that embed domain names.  Others include message headers,
SMTP, URIs, ssh keys, PGP keys, and on and on.  All these protocols, and
the software that implements them, will need to be revised if domain
names are allowed to contain non-LDH characters.

Also note that if ACE is a transition to UTF-8, then there are really
two transitions: one from LDH-only to ACE, and another from ACE
to UTF-8.  If ACE is seen as the solution, then there is only one
transition.

Finally, note that UTF-8 has issues with encoding efficiency (the length
of the encoded string).  It's excellent for Latin scripts, good for CJK
scripts, bad for some other popular scripts like Cyrillic and Arabic,
and horrible for most Indian and southeast Asian scripts.  UTF-16 is
excellent for CJK and bad for everything else.  An ACE can be designed
to be more balanced, achieving good or at least decent efficiency for
all scripts.

AMC