Follow-up to Monday's discussion of digits

[Andrew Sullivan]

On Wed, Nov 26, 2008 at 08:26:52AM -0500, Vint Cerf wrote:
> Alireza,
>
> surely it is apparent that this problem (letter I and number 1 or letter 
> O and number zero) is of ancient origin and it is far too late to 
> introduce repairs at protocol level. That would impact ACE encodings 
> among other things.
>
> On the other hand, the situation with multi-lingual use of the arabic  
> script is a current matter and we have an opportunity to adopt practices 
> that can learn from the past.
>
> It appears that many of your colleagues find the ban on mixing of  
> European, Arabic-Indic and Eastern Arabic-Indic either reasonable or  
> even necessary.

It seems to me this exchange is landing us squarely back into the
issue of confusability, and we already adopted a principle that
confusability rulings ought to be made by registries and handled by
policy, rather than getting bound up in the protocol.  Confusability
isn't enough for the restriction in the protocol.

John's argument for some restriction (in Minneapolis) was, I thought,
dependent on the premise that a majority (or siginficant minority) of
user agents do so many funky things with the encoding in between the
keyboard and the wire that it's all but impossible to guarantee
results without this change to the protocol.

Without that premise, I don't think there's any principled way to
include the restriction in the protocol.  Therefore, we need to know
whether the premise is true.

A

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