RE: two-week review: registering formal "rdns" NID

["Ing-Wher (Helen) Chen" <[e-mail]>]

Hello again,

I've taken Dale's advice to restrict the rdns URNs to be entirely lowercase
letters (by eliminating uppercase letters in <URN chars>), to bypass the need for
case-insensitive and case-sensitive comparison for lexical equivalence.
The latest version is -05.

URL:            https://www.ietf.org/internet-drafts/draft-chen-rdns-urn-05.txt
Status:         https://datatracker.ietf.org/doc/draft-chen-rdns-urn/
Htmlized:       https://tools.ietf.org/html/draft-chen-rdns-urn-05
Diff:           https://www.ietf.org/rfcdiff?url2=draft-chen-rdns-urn-05

The diff between the latest version -05 and the previous version I posted 
on this list, -03 (not -04), is here:

<https://www.ietf.org/rfcdiff?url1=https://www.ietf.org/archive/id/draft-chen-rdns-urn-03.txt&url2=https://www.ietf.org/id/draft-chen-rdns-urn-05.txt>

Thanks,
Helen

> -----Original Message-----
> From: Ing-Wher (Helen) Chen
> Sent: Monday, February 22, 2016 5:38 PM
> To: 'Martin J. Dürst' <[e-mail]>; Dale R. Worley
> <[e-mail]>
> Cc: [e-mail]
> Subject: RE: two-week review: registering formal "rdns" NID
> 
> Hi Martin and Dale,
> 
> Thanks for pointing out that "urn:rdns" should be case insensitive.
> I've updated the section on "Rules for Lexical Equivalent".
> 
> URL:            https://www.ietf.org/internet-drafts/draft-chen-rdns-urn-03.txt
> Status:         https://datatracker.ietf.org/doc/draft-chen-rdns-urn/
> Htmlized:       https://tools.ietf.org/html/draft-chen-rdns-urn-03
> Diff:           https://www.ietf.org/rfcdiff?url2=draft-chen-rdns-urn-03
> 
> Thanks,
> Helen
> 
> > -----Original Message-----
> > From: Martin J. Dürst [mailto:[e-mail]]
> > Sent: Friday, February 19, 2016 11:09 PM
> > To: Dale R. Worley <[e-mail]>; Ing-Wher (Helen) Chen
> > <[e-mail]>
> > Cc: [e-mail]
> > Subject: Re: two-week review: registering formal "rdns" NID
> >
> > Hello Dale, Helen, others,
> >
> > Indeed as Dale says, the "urn" and "rdns" components are
> > case-insensitive, and a namespace registration cannot change that.
> >
> > Regards,   Martin.
> >
> > On 2016/02/20 05:41, Dale R. Worley wrote:
> > > Comments on draft-chen-rdns-urn-02:
> > >
> > > "Ing-Wher (Helen) Chen" <[e-mail]> writes:
> > >>> Comments on draft-chen-rdns-urn-00:
> > >>
> > >> [Helen]  Just a note that at the time that I submitted to
> > >>                 [e-mail] for review, the latest version was -01.
> > >
> > > I should have noticed that!
> > >
> > > I think your changes take care of the problems that I've noticed.
> > >
> > >>> The rule for lexical equivalence can't be implemented because
> > >>> there is no algorithm for parsing an "rdns" URN into <reverse-dns>
> > >>> and <dss>, and the lexical equivalence rule specifies that
> > >>> <reverse-dns> is case-insensitive and <dss> is case-sensitive (as
> > >>> far as I can tell; you
> > should update the wording).
> > >>
> > >> [Helen]  I updated the section on "Rules for Lexical Equivalence".
> > >> On
> > second
> > >>                 thought, because "rdns" URNs are meant to be XML
> > >>                 namespaces of enterprise YANG modules, I think the
> > >>                 rules for lexical equivalence for "rdns" URNs should be
> > >>                 as defined for those of XML namespaces.
> > >
> > > There might be a problem, as RFC 2141 prescribes that "urn" and the
> > > NID
> > > ("rdns") are case-insensitive, whereas the draft prescribes that all
> > > of the URN is to be compared case-sensitively.  Looking at RFC 3406,
> > > the definition of the NID registration template, Appendix B.1 gives
> > > an
> > > example:
> > >
> > >     Rules for Lexical Equivalence:
> > >
> > >        FQDNs are case-insensitive.  Thus, the portion of the URN
> > >
> > >                    urn:<assigned number>:<FQDN>:
> > >
> > >        is case-insensitive for matches.  The remainder of the identifier
> > >        must be considered case-sensitive.
> > >
> > > The syntax for rdns URNs is
> > >
> > >         "rdns" URN    ::= urn:rdns:<reverse-dns>:<dss>
> > >         <reverse-dns> ::= registered domain name in reverse, each label
> > >                           separated by a colon (":")
> > >         <dss>         ::= 1*<URN chars>
> > >
> > > I think we are constrained to require (for URN comparison) that "urn"
> > > and "rdns" be case-insensitive, whereas you can specify whatever
> > > rule you want for the reverse-dns and dss parts.
> > >
> > > But perhaps other people on this list have more knowledge of how
> > > this issue has been handled for other URN namespaces.
> > >
> > > Dale
> > >
> > > .
> > >