Simon Josefsson <simon plus idn at josefsson dot org> wrote: >> It has never been a goal of IDN to create equivalence between >> different character sets. > > This means IDN is not guaranteed to be secure on non-Unicode systems. > There are alot of non-Unicode systems out there today... This problem, which IMHO is overstated anyway, is not confined to Unicode. AFAIK there are no *formal* equivalence tables between all the possible overlapping character sets in existence, whether mapping through Unicode or not. That means if you want your domain name searches to match *only* for the character set you are using, things are fine, but if you want the search to span across different character sets, you are no better off without Unicode than with it, because any mapping tables are informal or proprietary. And without Unicode, the user (or browser or mail agent) is required to declare the encoding for EVERY domain name and derived identifier it sends, because there is no other "obvious" default. ISO 2022 doesn't solve this problem because you still need mapping tables. It's easy to blame the big, monolithic, high-profile Unicode Consortium for "dropping the ball," but their responsibility is to create and maintain Unicode and provide "best available information" mappings for everything else. That is what they have done. They don't create or maintain other standards; national bodies and vendors do. And those national bodies and vendors have extended their standards in proprietary ways, while browsers and e-mail clients have been loose in character encoding terminology (e.g. Outlook Express allows me to format this message in "JIS," which could mean many things). Neither Unicode nor IDN, nor any other body, can be responsible for providing official, authoritative mappings for every character set and corporate extension out there. If national bodies and corporations have *official* mappings between their standards and Unicode, then perhaps those organizations can contribute them to Unicode (and promise to maintain them regularly and promptly!) so they are available in an easily accessible, central location. -Doug Ewell Fullerton, California