Re: [idn] I-D ACTION:draft-ietf-idn-idna-08.txt

[Patrik Fältström <paf@cisco.com>]

--On 2002-06-09 17.47 -0500 "Eric A. Hall" <ehall@ehsco.com> wrote:

>> I'm not sure what you mean by "encoding form".  The ACE form (which
>> involves both Nameprep and Punycode) is not guaranteed to be reversible
>> to the original capitalization.
> 
> Okay, that's a problem. May have to use something else entirely.

The problem is not capitalization. If you ask for preservation, you should
ask for preservation of the original string. Just looking at case
preservation is a very very tiny issue.

In the beginning (eons ago) we looked at the ability to keep the original
string, and the conclusion was that that was not possible without doing a
lot of changes to how DNS works, or at least, create new RR types which
include both the string one do comparison on, and the one which is given
back. Question is then how to see that the relationsship between them stays
the same etc etc.

But, DNS doesn't work that way _today_. It uses one string to match on, and
that is also the string which is given back. If a different string is given
back, many resolvers reject the strings due to risk of cache-poisoning.
And, caches will have issues with it, and the compression algorithm and...

The list is long, very long.

So, the result was that at the end, we always to conversion of strings when
they go "into the system" of application and DNS protocols. Within that
world, that f(X) is what is used. Period.

   paf