idna-bis and 'ß'

Paul Hoffman phoffman at
Fri Nov 23 16:06:10 CET 2007

At 6:07 PM -0500 7/26/07, Thomas Roessler wrote:
>In the current IDNA environment, the 'ß' character (latin small
>letter sharp s) is mapped to the all-Latin string "ss".  Therefore,
>no traces of that character can be found in zone files or
>registration databases; however, references to domain names (even
>all-ASCII ones) can be written in that fashion, and presented on
>business cards, in printed material, and in IRIs.
>I understand that the current state of idna-bis would lead to
>treating 'ß' as a "usual" character, causing a different encoding of
>relevant input strings.  Taking that step in idna-bis would cause
>existing references written with the 'ß' character (and possibly
>resolving to all-ASCII domain names) to break.
>As a cure, the current mapping behavior should be preserved as an

To Patrik, John, et. al.: Is there a list of characters from IDNA 
that are mapped to ASCII that are proposed to map to non-ASCII in 

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