Changing the xn-- prefix

Shawn Steele Shawn.Steele at
Wed Mar 26 02:13:20 CET 2008

> If all chars in the label can be represented in Unicode 3.2, xn--
> domains are generated, otherwise xx--. On the reverse, a sanity check
> is mandated for all xx-- that its round-trip must end up with xx--
> label otherwise it fails.

In that case a prefix change isn't necessary since the set of labels being added (those after Unicode 3.2) won't conflict with the existing xn-- space anyway.

> I suggest we remain silent on whether prefix change.

As I've said before, I think the amount of disruption such a change causes warrants very strong language opposing it.  Your example isn't as disruptive, but it also doesn't require a change in prefix.  I'll happily reconsider my position if someone has a strong case where it is necessary AND non-disruptive, but so far none have been presented.

Assuming we use the "MUST NOT have a prefix change" language, then if a case is discovered that is severe enough to require a prefix change, I would imagine that we would readily gather the consensus to change the charter.  If that consensus wasn't easy to get, then probably the need wouldn't be great enough to warrant a change in prefix.

- Shawn

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