Venn diagram in -defs-06

John C Klensin klensin at
Tue Mar 3 20:53:43 CET 2009

--On Tuesday, March 03, 2009 14:41 -0500 Andrew Sullivan
<ajs at> wrote:

> So, in case it wasn't clear before, in my opinion the diagram
> as it stands is not consistent with the definitions in the
> document; but it can be made consistent just by drawing a box
> around the text I already indicated.  Other than that, I think
> the diagram is useful.

The additional box is in the queue and will be in -07, assuming
I can make it fit, unless I hear objections RSN.

> It is possible to construct an argument that a bit string
> label could happen to fall entirely inside the 7 bit range and
> not be an "ASCII label" as such.  As far as I can see, there
> would be no way to tell the difference between such a bit
> string label and an ASCII label, so I don't grasp how the
> additional distinction will help understanding.

If you substitute "binary" for "bit string" in the comment
above, I agree.

If you stick with "bit string", then the label type indicator
should do the job.

Unfortunately, any confusion about terminology in IDNA draws on
extensive DNS precedent.   Any comments about the clarity and
precision of that DNS terminology should be referred to wherever
you would like to refer it.  

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