Idna-update Digest, Vol 31, Issue 26

[Shawn Steele]

Paul replied...

>> Which is what I meant.  Mapping is RECOMMENDED.  Valid cases not to map may exist.

> And they are....? You can't say to implementers "you must understand the
> full implications of not doing this" with giving them any clues.

I said that there should be clues.  What I'm saying is that we need to provide guidance for wise decisions, but it has to be high-level, we can't micromanage how apps work.

>(I also don't find the "go look it up" response very helpful, it is much more helpful to quote the relevant text and indicate where you see the problem instead of making all of us go look it up and guess where you see the problem)

> Noted. But I also note that you stopped after the definition for SHOULD,
> and didn't quote from section 6 of the document, which is in many ways
> more appropriate for this discussion.

Ah, I believe I was asked to look up "SHOULD".  I don't recall the text of 6 and must go attend a play so will not look it up at this time.

> During the recent discussions, many people have said the opposite: mapping
> can happen between the user's brain and the beginning of the application
> receiving the information.

Anyone expecting that from users has not participated in software usability studies.  It's pretty much a non-starter.

> So, are you saying that "address books SHOULD NOT map"? Or "address books MAY map"?
Yes :)  They need to pick.  Which is my point.

> Almost half of the developers who create software that uses IDNA2008 will have
> below-average understanding of what the full implications of skipping or changing
> the mapping is.

I do not allow for changing the mapping.  Applications MUST map consistently.

I agree there's risk, which is why I say SHOULD map, hopefully then they'd err on the side of mapping.  Also I think that they should have "clues"

For specific cases which we understand very well (maybe browsers and hrefs) we could be very explicit.  But I think that a huge catalog of MUSTs would only introduce errors.  If we say SHOULD, then hopefully only those with a great understanding and well thought out cases will skip the step.

If you'd like, I can live with saying that mapping MUST be done.

-Shawn