Re: [idn] Debunking the ACE myth

[Dan Oscarsson <Dan.Oscarsson@trab.se>]

D. J. Bernstein said:

>
>Wrong again. UTF-8 poses no problems for DNS servers. As Mark Andrews
>says: ``UTF8 does not require a server upgrade.''
>

No that is not correct. For both ACE and UTF-8 there are two
ways that it can be done:
1) All names are transmitted in a form/semantic insensitive format
   (that is what nameprep is for) so that names can be compared
   using binary matching.
   
   In this case a server upgrade is NOT required.
   
2) Names are transmitted with form retained (that is any form, though
   they should be normalised).
   In this case the applications that do name comparing need to to
   convert them into the form/semantic insensitive format before comparing
   them (or do it on the fly while comparing them).
   
   In this case the DNS servers need to be upgraded.
   
   
1) Is the IDNA case and also in Microsofts draft-skwan-utf8-dns.
   This results in that for example upper case characters cannot be
   used in responses from DNS. Probably very irritating some people
   who have spent a lot of mony on their nice company name which uses
   mixed case and will break some programs expecting mixed case
   in PTR responses.
   

   Dan