Re: [idn] Prohibit CDN code points

[Patrik Fältström <paf@cisco.com>]

--On 2002-01-22 09.37 +0900 Masahiro Sekiguchi <seki@jp.fujitsu.com> wrote:

>     For example, .cn domain can say "SC/TC mapping must be 
>     enabled for .cn" if it considers that decision serves the
>     .cn domain name users best.  If another domain, say .us,
>     finds contrary, it can say "SC/TC must be disabled for .us".

This will not work because _all_ DNS servers in the world need to be able
to fulfil matchings according to the rules the .cn TLD decides. That in
turn means that all DNS servers need to have matching rules which is the
sum of _all_ rules _all_ TLD's define (and subdomains to TLDs etc, because
of course I want a special matching rule for my subdomain of .com!).

This in turn leads by definition to one to me very complex matching
algorithm which is context dependent and not one for each domain in the
world.

Noone have come up with such an algorithm.

And, one thing DNS likes is when one label have the same matching algorithm
regardless of what "neighbour" labels are in the DNS packet. Leaving this
strategy and have different matching rules for the same octets depending on
context is a _very_ big change to all existing DNS implementations.

Don't go there.

   paf