Lookup for reserved LDH labels

Marcos Sanz sanz at denic.de
Wed Nov 7 10:55:56 CET 2012


> mark is correct.

that is not incompatible with my statement. He said

"the intention is to permanently reserve anything of the form "xy--..." 
(where x and y are in [a-z0-9]"

and I agree with that.

> "putative" means that the "--" appears in 3rd and 4th position of 
> the string - it means the label purports to be the prefix of a U-label.

The definition of "putative U-Label" (a.k.a. "unvalidated" or "apparent" 
U-Labels) is found in the last paragraph of Section

"unvalidated U-labels are simply non-ASCII labels that may or may not meet 
the requirements for U-labels."

Thus "ad--acta.de" (plain ASCII) is not a putative U-Label and must not be 
subject of any of the validation bullets listed in the lookup Section 5.4.

Best regards,

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