Consensus Call on Latin Sharp S and Greek Final Sigma

Wil Tan wil at
Tue Dec 1 08:12:42 CET 2009

> (1) Both characters should be PVALID

I support the above position. While I'm concerned about the
transitioning issues, I believe that biting the bullet and having
equivalence of U-label and A-label forms will go a long way in
ensuring a clean protocol.

Transitioning is about raising awareness and educating the parties
involved: developers, users, registries, registrars, registrants.
These are not the only two characters that has compatibility
implications so we have work to do anyway.

Outside the protocol, I support the adoption of UTS46 as part of the
transition, possibly along with mechanisms to educate the users to
rely less on mapping.

I don't believe we have heard from other registries, especially gTLDs,
who started accepting IDN registrations early on and specifically
advertised "German IDN" which would've created the expectations among
registrants that ß can be used. So, .DE and .AT are aware of the
changes, but I'm not sure if others know what they're in for. For
example, .INFO in their IANA table, says:

> The Eszet Character: ß
> Based on the Nameprep [RFC3491] specification for a Stringprep [RFC3454] profile
> for IDNA [RFC3490], the Eszet ß character used in the German script will be mapped
> to a double s string (i.e. ss).

They need to be aware that eventually links will break and what used
to be resolvable will either stop working or go to someplace else
unless they do something to minimize the ill-effects.


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