What registries might do (was: Consensus Call on Latin Sharp S and Greek Final Sigma)

[Andrew Sullivan]

On Mon, Nov 30, 2009 at 03:52:15PM +0100, Georg Ochsner wrote:

> it takes time. At the end nic.at can also refuse to have sharp s registered
> at all, not even thinking about a possible rollout. So my recommendation
> would be to keep the possibilities open for the future because circumstances
> may change in the near and far future. There should be no exigent reason for
> you to bury the sharp s today for all time. And finally mappings like in
> 2003 will no longer be part of 2008 anyway.

But to be fair, the "registry completely restricts" policy won't work
if ß is PVALID in IDNA2008.  Suppose .at by policy excludes (and
doesn't map) ß.  What will happen then is that IDNA2003 clients will
map ß to ss, and so a label ${example}ß.at will work for them; when
the human on the other side of that client does its next upgrade,
${example}ß.at suddenly stops working.  This is the problem that
opponents of making ß PVALID are talking about.

The complication is worse for ς, but it is approximately the same
issue.  In both cases, we're talking about changing an existing
namespace not just so that new possibilities are now availabl.  So
this is not "just" a sunrise.  The deployed code, as it stands,
actually allows those proposed new parts of the namespace to function
_today_.  So what we are talking about is altering deployed behaviour.
I think therefore that the opponents of PVALID have a perfectly
reasonable point, and we do ourselves no service to wave them away.  

This is particularly important because some of the people who are
objecting loudest and longest about this change are in fact the ones
who _will_ implement mappings like in IDNA2003, whether one likes it
or not.  The plain fact is that it is the announced intention of some
implementers to create such mappings, in an effort to make things
backward compatible.  Therefore, I think Mark Davis is correct,
upthread, to point out that the question the Chair has put to us does
not explicitly mention the practical effects of the choice.  (For what
it's worth, I think the Chair's question is entirely proper anyway,
because it asks in stark terms precisely what the documents must say.
In answering, however, we must consider the practical effects of what
we choose.)

Best,

A

-- 
Andrew Sullivan
ajs at shinkuro.com
Shinkuro, Inc.