[Errata Held for Document Update] RFC5890 (4823)

[John C Klensin]

Martin and Markus,

As you may have guessed from my response to Jefsey, I largely
agree about the erratum.  I was just trying to get a bit ahead
on the document and this comment --for the distribution of which
I've removed the RFC Editor and IESG-- is very much in
anticipation of a future update that is not now on the radar.  

After reading and thinking about your notes, I now believe that
it is probably useful to explain what is going on and why, but
that, as you surmise, there may be two types of readers.  For
those who are adequately familiar with Unicode, a comment in
terms of code points is likely to be sufficient and comments
about encoding forms will either add nothing or be confusing.
For someone without that level of knowledge, a comment about the
compressibility of various encoding forms is not likely to be
helpful and we really need to figure out how to explain what is
going on.  I recommend the task of figuring that out as an
exercise for the authors and contributors to that future
revision (if you have ideas/ suggestions, write me off-list and
I'll add it to my collection of pre-IDNA2008bis materials).

best,
    john


--On Saturday, October 08, 2016 19:23 +0900 "Martin J. Dürst"
<duerst at it.aoyama.ac.jp> wrote:

> Hello Markus, John,
> 
> I would be fine either way, but I'd at least keep the current
> wording for the errata for the following (partially
> overlapping) reasons:
> 
> - The main point of an erratum (in my view at least) is to fix
> a clear
>    problem, not to engage in detailed wordsmithing.
> - The errata review process isn't at the same level as a WG
> process,
>    so trying to find a final wording on the erratum sounds
> slightly
>    premature.
> - I don't think "held for document update" does in any way
> imply
>    that the update has to use the exact wording.
> - The current RFCs have counts like 236. The explanations that
> were
>    just approved as errata help see where this number came
> from.
>    This is (somewhat) more important in an erratum (which is
> approved
>    just on the level of AD) than in a new document (which is
> approved
>    by IETF consensus).
> - The error was not just a calculation error; I think there
> was indeed
>    an intent in the WG to warn implementers about the
> expansion problem).
> 
> Also, Markus said: "Anyone dealing with Unicode strings has an
> idea how they store them.". I'd say: "We'd better hope so!".
> But implementers in the DNS area are not necessarily familiar
> with Unicode strings. So a hint can help, and shouldn't hurt.