referencing IDNA2008 (and IDNA2003?)

Andrew Sullivan ajs at
Fri Oct 22 00:21:59 CEST 2010

On Thu, Oct 21, 2010 at 05:45:51PM -0400, John C Klensin wrote:
> 	(2) The application insists that all IDNs, including
> 	especially what is stored in cookies, use A-labels and
> 	then behaves in a fashion that is as ignorant as
> 	possible as far as details & versions of IDNA are concerned.

I will note that my personal preference is very much this option.  I
think it would be an excellent idea to suggest that this is the best
option, because it's the most interoperable (IDNA-ignorant systems
don't spit up on it, for instance), because it's always possible to
get the U-label back out, and because it means that you do the
A/U/A/U-label dance only one time, at the end, when it's time to
display.  But if people are going to put U-labels anywhere, I agree
with John that the best advice we can give is "follow the rules".


Andrew Sullivan
ajs at
Shinkuro, Inc.

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