Domain names with leading digits (Re: Determining the basic approach)

Harald Tveit Alvestrand harald at
Mon May 5 07:48:12 CEST 2008

Paul Hoffman skrev:
> Greetings again. According to our charter, one of the first tasks of 
> this WG is to determine whether we are going to make "a change to the 
> basic approach taken in the design team documents". To that end, I 
> have circulated a few versions of a draft that lists all of the basic 
> approaches embodied in the current design team documents:
> In order to make our deadlines (and I really like Patrik's suggestion 
> in his most recent document that we call this effort IDNA2008 so we 
> try to meet that goal), we should start that discussion sooner rather 
> than later.
> Using the draft's numbering of topics that are different between 
> IDNA2003 and the design team documents,
> I support the WG adopting: 1, 2, 3, 4, 5, 6, 7, 10,
> I am neutral on the WG adopting: 8, 9
> I am against the WG adopting: 11, a, b 
I THINK, but do not know, that what Paul means by:

   11.  Make some currently-legal, non-IDNA labels illegal

is pointed at this piece from -bidi:

   When labels pass the test, they can be used with a minimal chance of
   these labels being displayed in a confusing way by a bidirectional
   display algorithm.  In order to achieve this stability, it is also
   necessary that the test be applied to labels occuring before or after
   the label containing right-to-left characters, which prohibits some
   LDH-labels that are permitted in other contexts.

The -bidi requirement that necessitates this test is:

   o  In a display of a string of labels, the characters of each label
      should remain grouped between the characters delimiting the

And the resulting rule is:

   o  The first character may not be an EN (European Number) or an AN
      (Arabic Number).

I don't know of any other part of the idnabis work that affects LDH-compliant labels.
(There's also the minor point of codifying the existing prohibition against leading and
trailing hyphen, but that's a stretch of the term "currently legal". If that was intended,
please holler.)


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