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

Paul Hoffman phoffman at
Mon May 5 16:26:21 CEST 2008

At 7:48 AM +0200 5/5/08, Harald Tveit Alvestrand wrote:
>I THINK, but do not know, that what Paul means by:
>   11.  Make some currently-legal, non-IDNA labels illegal
>. . .
>And the resulting rule is:
>   o  The first character may not be an EN (European Number) or an AN
>      (Arabic Number).

Correct, in part (see below). This rule prohibits thousands of 
current domain names like,, and a whole lot 
of others. It could be changed to be a registry recommendation 
instead of a prohibition on all labels, even ones that don't appear 
in IDNs.

>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.)

There is a second place. In draft-klensin-idnabis-issues-07.txt, 
section prohibits labels that have a hyphen in positions 3 
and 4 unless they are A-labels. This is completely unnecessary.

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