<br><br><div class="gmail_quote">On Wed, Sep 2, 2009 at 12:36 AM, Andrew Sullivan <span dir="ltr"><<a href="mailto:ajs@shinkuro.com">ajs@shinkuro.com</a>></span> wrote:<br><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex;">
<div class="im">On Tue, Sep 01, 2009 at 02:14:37PM +1000, James Mitchell wrote:<br>
><br>
> Punycode does not require output to be in any particular case. I<br>
> have copied from RFC3492 Page 8 below for convenience<br>
><br>
> 'An encoder SHOULD output only uppercase forms or only lowercase<br>
> forms, unless it uses mixed-case annotation'<br>
><br>
> Therefore KGBECHTV and kgbechtv are both valid outputs of the<br>
> punycode algorithm.<br>
<br>
</div>Hrm, so actually it is possible that all ASCII characters in an<br>
A-label are upper case, even though the input from the U-label is not<br>
allowed to have upper case in them. This seems to be bad, because the<br>
returned result from the Punycode decoding could make the U-label<br>
ASCII characters upper case, right?<br><br></blockquote><div><br></div><div>Yes, that's indeed a good catch, James.</div><div><br></div><div>I haven't encountered any implementation that encodes using uppercase characters as output, though I can't claim to have seen them all.</div>
<div><br></div><div>=wil </div></div>