Re: [comment] URI/IRI canonicalization in powder-grouping

On 2007-11-14 12:43:24 +0100, Thomas Roessler wrote:

> - It is not clear to me whether you want to consider a
>   human-readable representation in case of internationalized domain
>   names occuring in the authority part of the URI, or whether you
>   consider the ASCII representation in that case.
>   This specifically affects the case-insensitive part of the host
>   name comparison (only US-ASCII domain names are case-insensitive).

On this topic, also note RFC 3490, section 2.

   In IDNA, equivalence of labels is defined in terms of the ToASCII
   operation, which constructs an ASCII form for a given label,
   whether or not the label was already an ASCII label.  Labels are
   defined to be equivalent if and only if their ASCII forms
   produced by ToASCII match using a case-insensitive ASCII
   comparison. ASCII labels already have a notion of equivalence:
   upper case and lower case are considered equivalent.  The IDNA
   notion of equivalence is an extension of that older notion.
   Equivalent labels in IDNA are treated as alternate forms of the
   same label, just as "foo" and "Foo" are treated as alternate
   forms of the same label.

Thomas Roessler, W3C  <>

Received on Saturday, 17 November 2007 22:36:40 UTC