Eszett and IDNAv2 vs IDNA2008

Shawn Steele (???) Shawn.Steele at
Thu Mar 12 22:55:56 CET 2009

> - If you try to look up a WHOIS record at Denic for a domain spelled
> with ß (e.g. süß you will get an error message that the domain
> is not valid. The registrant who registered sü never had two
> domains, people just had the option, that in some applications (featuring
> INDA2003) they were redirected from süß to his domain instead of
> getting an error.

That's what IDNA does.  Of course süß doesn't work, IDNA makes that work by mapping ü and ß. So if you now tried to register süß with an IDN aware registrar, it would find the existing domain sü and disallow the new registration.  Ergo süß *IS* currently a valid domain, registered to the same person that owns sü (because they're the same).

Having a distinct mapping for süß in a future version of IDN would break the current behavior.  That might be acceptable, but I seriously doubt it is worth the effort and risk.  Suppose you have the domain name "" in English.  Probably someone's name or something.  What about ""?  Completely different meaning.  ß and ss can probably coexist just like casing does.

Consider a little-used word like Fußball and point it somewhere other than  Regardless of the linguistic subtleties of some words, most users will expect ß and ss to behave the same.  Even if it weren't true in Germany, would a German web site really want to risk that a Swiss or Austrian customer might hit a competitor's site?

So what if someone can't register buß and someone else  AAA Locksmith can't register either.  The problem isn't that they both NEED to be distinct and registerable.  The problem is that one you've registered it, you need to tell people whether you're gonna help with their busses or psyche, so you need a decent way to show your preferred display name.

- Shawn

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