Re: [idn] IDNA applicability: per RR/Class or DNS-wide

["Adam M. Costello" <idn.amc+0@nicemice.net.RemoveThisWord>]

"Eric A. Hall" <ehall@ehsco.com> wrote:

> > If we allow multiple profiles, that's the same as allowing different
> > comparison rules for different labels.
>
> The question formation differs, comparison is identical.

We're just using different terminology.  When I say "comparison",
I'm refering to everything involved in the comparison, including the
preparation, even if it's done at a different time.

Consider this scenario:  One user types a domain label containing an
uppercase letter O-umlaut, another user types a domain label containing
a lowercase letter o followed by a combining umlaut.  Do these two
labels match?  Yes, no, or "well maybe, it depends"?  For ASCII domain
names, the answer has never been (and never will be) "maybe", there
is always a yes or no answer that is apparent to anyone, without any
additional information.  That simple model underlies everything that
has been built on top of domain names.  I think trying to work out the
implications of throwing "maybe" into the mix is more trouble than it's
worth.

AMC