AW: Sharp-S and Final Sigma Consensus Call Results

Vint Cerf vint at
Wed Dec 9 22:13:13 CET 2009

in the absence of another other non-LDH character,
the label with the sharp-S loses its U-Label-ness and
becomes simply an LDH string when sharp-S is mapped
into "ss". I understand your point, however, to be that
it sort of depends on when and where the mapping
takes place.


On Dec 9, 2009, at 4:02 PM, Andrew Sullivan wrote:

> On Wed, Dec 09, 2009 at 03:55:48PM -0500, Vint Cerf wrote:
>> wouldn't mapping of pvalid chars would disrupt the A-Label/U-label
>> equivalence?
> Well, what do you mean by "mapping"?
> Suppose ß were PVALID.  If an application always took "ß" and
> converted it to "ss" before handing it to the IDNA subsystem, how is
> the U-label spelled?  With ß or ss?  (I can make an argument either
> way, I think.)
> A
> -- 
> Andrew Sullivan
> ajs at
> Shinkuro, Inc.
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