<access> and IRI equivalence

Two points:

1. I think it's a good thing to phrase this in terms of the BNF from  
3986 and 3987.  I don't think it's obvious that this piece of the spec  
needs to reuse the HTML URI parser.

2. Equivalence of ASCII domain names is defined in terms of an ASCII  
case insensitive comparison.  Equivalence of IDN labels is defined in  
terms of case insensitive comparison of their ASCII representations.   
Given various troubles and instabilities in IDN space, the only IDNs  
that can be put into files safely are U-labels, i.e., labels that are  
mapped onto themselves when ToUnicode is applied to the result of  
ToASCII.

The relevant references here are:

   http://tools.ietf.org/html/rfc3490
   http://tools.ietf.org/html/draft-klensin-idnabis-issues-07

You'll also want to say something about URI encoding in the path part  
of the IRI reference.

Regards,
--
Thomas Roessler, W3C  <tlr@w3.org>