RE: [idn] Re: stringprep and unassigned code points

[Paul Hoffman / IMC <phoffman@imc.org>]

At 4:34 PM -0800 10/30/01, Yves Arrouye wrote:
>I will be glad to understand that I am wrong in saying that this scenario
>shows that some queries from older applications won't have the expected
>result against more recent servers (older/recent as far as Stringprep goes).
>But can you please point out where my reasoning is then?

"won't have the expected result" is quite different than "breaks". In 
your scenario, the application has no idea what the expected result 
is. The application simply knows that it is entering a character that 
is (according to the version of nameprep it is using) unassigned. 
Thus, a response of "no such name" makes perfect sense to the 
application. Remember, the client might be talking to a server that 
is using the same version of nameprep, and such a server will 
certainly generate "no such name" for any name that contains an 
unassigned character.

There is no expectation that entering random unassigned characters 
will work. As you point out, those characters may be mapped or they 
may be prohibited in the version of nameprep that is running on the 
server. Further, even though the server might be running newer 
software, the character might still be unassigned.

In short, a client has no particular "expected result" for a query 
with unassigned characters in it.

--Paul Hoffman, Director
--Internet Mail Consortium