Outstanding issues(2): Rationale document

[John C Klensin]

In the hope of getting some discussion going that focuses on 
unresolved issues in the WG's charter, I'm about to post four 
notes that contain a list of substantive outstanding issues and 
loose ends with the documents for which I hold the pen.   This 
is the second of those four.  Please, for all four, if you open 
up significant new topics, change the subject line.   And, for 
this one and the third and fourth, please use separate threads 
for each issue so that we can discuss them, rather than 
addressing omnibus notes to the editor: if these topics were not 
at least somewhat uncertain or controversial, they would have 
been resolved and reflected in the documents by now.

draft-ietf-idna-rationale-00 contains explicit questions or 
placeholders for the following issues.  Additions to the list 
would be welcome (please start separate threads, as mentioned 
above).  Discussion on these issues is important if we are going 
to start converging at least on the issues about which we agree 
and those that need further discussion.  Again, please used 
separate threads that identify the particular issue.

Of course, if we decide to drop the Rationale document entirely 
(see the note about Document Organization), most of what follows 
becomes irrelevant although discussion of what material, if any, 
should be retained and moved elsewhere would become important.


** PROTOCOL-VALID Explanation

    Section 6.1.1 contains an overview of Protocol-Valid.  Is
    that explanation adequate?  If more is needed, what?
    Suggested text would be appreciated.

** Contextual rules and their application

    Section 6.1.1.2 contains a discussion of contextual rules
    and a placeholder for an in-depth explanation of the syntax
    for those rules.  This material is really part of the fourth
    note in this series (on Contextual Rules and their
    definitions), but this section should be examined carefully
    for clarity at least.

** Permanence of DISALLOWED

    There has been extensive on-list discussion about whether
    migration of characters from DISALLOWED to PROTOCOL-VALID
    (or CONTEXTO) should be easy, or at least easier than
    migration from PROTOCOL-VALID to DISALLOWED.   I do not
    believe we have reached consensus even though the material
    in 6.1.2 reflects what I believe to have been the general
    trend of the discussions when they ran down.  Does anyone
    have anything new to say about this and, if not, should I
    remove the placeholder?

** User agents and warnings

    The last paragraph in Section 6 (actually 6.3 on layered
    restrictions) explicitly points out the role of user agents,
    and then concludes with a warning against threats that
    cannot be completely prevented or blocked.   That sentence
    is redundant with a disclaimer in Security Considerations.
    Should it be removed (I believe that someone explicitly
    asked that something along these lines be said in 6.3, but
    it is redundant, so I'm checking).  Silence will be
    interpreted as "leave the text, drop the placeholder".

** Explanation of removal of symbols

    Section 10.5 discusses the reasons why symbols are not
    permitted in IDNA2008.   There has been controversy about
    some of the statements and examples, with some disagreement
    about whether some of them are even factually correct.   We
    either need to identify everything that is controversial out
    of this section and trim it out (which might leave very
    little), fix specific examples on which we can agree, accept
    (and possibly note) the disagreements, or adopt some other
    strategy.    Of course, if we drop rationale and explanatory
    material in favor of a "this is just how it is" approach,
    the specific issues with this section vanish.

** Mechanisms for updating the context registry

    Section 13.2 ("IDNA Context Registry") contains a discussion
    of the updating rules for the Contextual Rules registry.
    This topic is discussed further in the fourth note of this
    series.

Again, if there are other significant issues, I don't have them 
marked and they should be identified as soon as possible.

     john