Comments on draft-ietf-idnabis-defs-10
james.mitchell at ausregistry.com.au
Tue Sep 1 06:14:37 CEST 2009
> > XN--KGBECHTV is a valid A-label;
> No. Because it cannot be produced by the defined transformation
> from a U-label, it is not. The difference between it an a valid
> A-label is harmless, and both translate back to exactly the same
> U-label, but that doesn't make it a valid A-label.
Punycode does not require output to be in any particular case. I have copied from RFC3492 Page 8 below for convenience
'An encoder SHOULD output only uppercase forms or only lowercase forms, unless it uses mixed-case annotation'
Therefore KGBECHTV and kgbechtv are both valid outputs of the punycode algorithm.
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