New versions of Protocol (-04) and Rationale (-02)

[Erik van der Poel]

On Tue, Sep 16, 2008 at 8:44 AM, JFC Morfin <jefsey at jefsey.com> wrote:
> At 17:09 16/09/2008, Erik van der Poel wrote:
>> If an attempt is made to convert the label to Unicode, the Punycode
>> decoding algorithm MUST be used, and if that fails, the label MUST be
>> rejected. If it succeeds, the tests in Section 5.5 and conversion in
>> Section 5.6 MUST be performed, and if either of those fail or the
>> resulting label is not identical to the original label that started
>> with "xn--", then the label MUST be rejected.
>>
>> Or is this beginning to look too much like the algorithmic description
>> found in IDNA2003?
>
> Since we know that:
>
> - 50% of the U-label cannot result in A-label using punycode

U-labels and A-labels are interconvertible (U-label <-> A-label) by
definition. That is why I was careful to use such terms as "label",
"Unicode" and "Punycode".

Maybe you meant "50% of all possible labels that start with 'xn--' are
not A-labels."?

Erik