Re: [precis] Ambiguity in specification of case mapping in RFC 7613 and draft-ietf-precis-nickname

[Peter Saint-Andre <[e-mail]>]

Thanks, John!

On 10/27/15 8:12 AM, John C Klensin wrote:
> I am most of the way through a response now... should be able to
> mail it within an hour or so if I'm not interrupted again; later
> today in any event.
>
>     john
>
>
> --On Tuesday, October 27, 2015 07:52 -0600 Peter Saint-Andre
> <[e-mail]> wrote:
>
>> This issue has greater urgency now because
>> draft-ietf-precis-nickname is now in AUTH48...
>>
>> On 10/26/15 3:51 PM, Peter Saint-Andre - &yet wrote:
>>
>>> After all that, I have 3 questions:
>>>
>>> (1) Is my proposed text enough of a clarification that we
>>> should make that change before the nickname I-D is published
>>> as an RFC?
>>
>> I think so.
>>
>>> (2) Should we modify draft-ietf-precis-nickname so that case
>>> folding is applied only as part of comparison and not as part
>>> of enforcement? If so, should we make that change before this
>>> document is published as an RFC?
>>
>> Although it seems to be the case that Unicode case folding is
>> primarily designed for the purpose of matching (i.e.,
>> comparison), I have a concern that applying the PRECIS case
>> mapping rule after applying the normalization and
>> directionality rules might have unintended consequences that
>> we haven't had a chance to consider yet. The PRECIS framework
>> expresses a preference (actually a hard requirement) for
>> applying the rules in a particular order. We made a late
>> change to the username profiles (RFC 7613), such that width
>> mapping is applied first (in order to accommodate fullwidth
>> and halfwidth characters in certain East Asian scripts).
>> Making a late change to the nickname profile also concerns me,
>> even though both of these late changes seem reasonable on the
>> face of it. I will try to find time to think about this
>> further in the next 24 hours.
>>
>>> (3) Should we update RFC 7613 so that case folding is applied
>>> only as part of comparison and not as part of enforcement?
>>
>> That is less urgent so I suggest that we address the nickname
>> spec first.
>>
>> Peter
>>