Re: [idn] lowercased hostnames (was: naming syntax rules)

["Eric A. Hall" <ehall@ehsco.com>]

Dan Oscarsson wrote:

> What I can see the names encoded in ACE for IDNA must be not just
> lower cased but also have all the transformations done on the
> characters without case, that we will define to match as equal.
> Otherwise IDNA will not work.

Right.

> But for solutions using native UCS (in the form of UTF-8) in the DNS
> protocol, we can allow DNS to work like today matching names
> case-insensitively.

Isn't this mutually-exclusive? If the hostname is defined with UCS
characters of mixed case, then the PTR will have to always provide that
case form, but ACE will not be able to provide the PTR data in mixed case.
Therefore, ACE will always break the PTR if a hostname is defined in mixed
case. And if people are allowed to define mixed case (the canonical UCS
form works), then they will always be getting shafted by ACE PTR RRs.

It seems that if we are forced to lowercase everything but ASCII for ACE
then we have to always lowercase everything but ASCII regardless of the
encoding that may or may not be used.

-- 
Eric A. Hall                                        http://www.ehsco.com/
Internet Core Protocols          http://www.oreilly.com/catalog/coreprot/