Re: §2.1.3 IRI/URI Canonicalization does not address IRIs with IDNs

Hi Eric (putting i18n core into the loop),

Eric Prud'hommeaux wrote:
> does not include IDN example or rules.

there is no need for an IDN example or rule. IRI vs. URI, and IRI>URI 
conversion (percent escaping) are a step, which is independent of 
preprocessing necessary for domain name resolution. See also the 
processing described at

> An example (working) IDN IRI:
>   http://www.bravå.nu/
> The IDN is punycoded when the IRI is expressed as a URI:
> == homonyms ==
> å can be written either Ue5 or 'a' + U30a (COMBINING RING ABOVE).
> This results in a different punycoded IDN. 

the punycode is only "seen" by the domain name server which uses it for 
domain name resolution. There is no need to use it for *IRI/URI* 

> Unicode gives *some*
> c14n (or folding) rules, but not all, and they are not cheap to
> implement.
> == fixing ==
> This should probably be addressed in an update of mnot's URISpace Note
> I recommend inserting in Punycode (or maybe IDN) Conversion:
>   • Internationalized Domain Names (IDNs) are converted from their
>     punycode form to Unicode code points.

where does this happen? Note that in IDNA version 2003, roundtripping 
Unicode > punycode < Unicode is not possible, since during the step 
Unicode > punycode, non-reversible mapping (e.g. Eszett > ss) are made. 
But as said above, I think this is out of scope for IRI/URI 


Received on Tuesday, 12 February 2008 00:48:44 UTC