Re: I-D ACTION:draft-ietf-idn-idna-08.txt

John C Klensin wrote:

> As has been pointed out, "undefined" means "undefined" and,
> given interoperability and the robustness principle, something
> that should not be (attempted to be) used.  It doesn't mean
> "non-alphabetic" -- that constitutes defining it.

They are "undefined" for interpretation, but they are "defined" as
eight-bit code values for the purposes of storage and transfer.

Consider the lowly cache. What if a client and server exchange eight-bit
domain names linked with an expiremental RR which the cache knows
absolutely nothing about? What if eight-bit owner names are explicitly
interpreted for that RR? Clearly there is only one interpretation that
works in the distributed model.

I suppose you could argue that the ~standard RRs from STD13 are special
and do not have any such meaning, although I would argue against it. You
could also argue that sending eight-bit codes with the ~standard RRs from
STD13 is a bad idea but not prohibited and I would agree with you.

-- 
Eric A. Hall                                        http://www.ehsco.com/
Internet Core Protocols          http://www.oreilly.com/catalog/coreprot/