Standards and localization (was Dot-mapping)

Yangwoo Ko newcat at
Thu Dec 13 03:05:30 CET 2007

John C Klensin wrote:
> (snip)
> depend on anything tricky.   I think what is needed here is not
> a part of the IDNA standard but a separate document that says, 
> 	If you are an implementer of something that calls a
> 	resolver and are in your right mind, you will accept
> 	anything plausible, including these explicit
> 	recommendations (the IDNA2003 list goes here), as a dot,
> 	nothing that they are all prohibited (as punctuation) in
> 	IDN labels.  you will do case mapping for any script for
> 	which that is defined (with a pointer to the Unicode
> 	mapping table), and so forth.  You will immediately map
> 	those to the target characters and make whatever
> 	decisions seem sensible to you about warning the user
> 	about what you have done (such decisions might range
> 	from silence to 'do you want me to do this' messages).
> 	And any registry in its right mind (including zones deep
> 	in the tree) should accept only those strings for
> 	registration that can be reversed-mapped from A-labels
> 	back to the U-labels, i.e., with no mappings from one
> 	character to another at all.
> I don't know what is in "and so forth", but I imagine that other
> cases will be discovered.  

Simplified <-> Traditional Chinese character equivalence/mapping (as 
exemplified in RFC3743) could be one of those "and so forth".

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