HYPHEN-MINUS

[John C Klensin]

Chris,

While I disagree with several aspects of your analysis, I think
you have correctly identified an edge case that exposes a bug.
Unless others disagree, I'm make the change to Protocol that you
suggest, meaning that Patrik can remove the contextual rule.

    john 


--On Wednesday, July 29, 2009 00:50 +1000 Chris Wright
<chris at ausregistry.com.au> wrote
>...
> To clear any confusion that may have arisen during limited
> discussion last week, the context rule is applied to the
> putative U-label, therefore the DNS and host name syntax
> restrictions do not apply (yet). Consider the label
> b[U+00FC]cher-. The output of this label through the punycode
> algorithm when appended with the ACE prefix gives gives
> xn--bcher--3ya. Note this label conforms to the host name
> syntax.  
> Thus for consistency, simplicity and clarity sake I propose
> the following:  
> In protocol change: 
> 
> 4.2.3.1. Consecutive Hyphens
> The Unicode string MUST NOT contain "--" (two consecutive
> hyphens) in the third and fourth character positions.  
> to
>  
> 4.2.3.1. Hyphen Restrictions
> The Unicode string MUST NOT contain "--" (two consecutive
> hyphens) in the third and fourth character positions and MUST
> NOT start or end with a "-" (hyphen).  
> And then remove the context rule from the tables document and
> return hyphen to PVALID status as with all other LDH characters
> 
> Thanks
> 
> Chris
> 
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