Re: IANA URN registration enquiry - Rules for Lexical Equivalence of NSS

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

First, you are quoting from draft-ietf-urnbis-rfc3406bis-urn-ns-reg, not
from RFC 3406. Until and unless the Internet-Draft you cite is approved,
RFC 3406 is still the operative specification.

Second, RFC 3406 says "If":

      If there are particular algorithms for determining equivalence
      between two identifiers in the underlying namespace (hence, in the
      URN string itself), rules can be provided here.

It is not necessary to define namespace-specific rules for lexical
equivalence. However, if you do then this part of the registration is
the place to describe them.

Third, yes it is true that the NSS is not registered with the IANA, but
the NID is registered and as part of the process of registering a NID we
want to make sure that the manager of the namespace has clear policies
and procedures in place for issuance of identifiers (i.e., URNs). One
such policy consists of the rules for lexical equivalence, if any.

Fourth, the IANA does not publicize the rules for lexical equivalence
for any particular namespace, but the RFC that is published as part of
the NID registration process does specify the rules (and the IANA
registry points to the RFC). As a result, anyone who wants to use
identifiers issued by the relevant NID manager can determine if there
are namespace-specific rules for that NID.

I hope that clarifies the matter.

Peter

On 4/21/11 9:48 AM, DTG Registration wrote:
> Dear Peter,
> 
> Thank you for your answer, the information provided does still not
> make clear why NSS lexical equivalence rules are required, if the NSS
> is not registered with IANA. The text in RFC 3406 implies that NSS
> lexical equivalence rules are required as part of the NID
> registration, see extract below.
> 
> Rules for Lexical Equivalence of NSS part:
> 
> [[ Editorial Note: This clause moved into vicinity of "syntax". ]]
> 
> [[ Editorial Note: In the past, there has been iterated trouble in 
> tentative registration documents with regard to what rules can be 
> imposed for lexical equivalence.  Since the "urn:" prefix and the NID
> part both are invariably case-insensitive per RFC 3986 and RFC 
> 2141[bis], in order to avoid repeated confusion, this version of the
> template tentatively restricts this clause to only the NSS part of
> the new URN namespace definition documents. ]]
> 
> { If there are particular algorithms for determining equivalence 
> between two identifiers in the underlying namespace (and hence, in 
> the URN string itself), rules can be provided here.
> 
> Some examples include: -  equivalence between hyphenated and
> non-hyphenated groupings in the identifier string; -  equivalence
> between single-quotes and double-quotes; -  namespace-defined
> equivalences between specific characters, such as "character X with
> or without diacritic marks".
> 
> Note that these are not normative statements for any kind of best 
> practice for handling equivalences between characters; they are 
> statements limited to reflecting the namespace's own rules. }
> 
> Perhaps I am unclear on the process after the urn has been
> successfully registered. Are NSS lexical equivalence rules stored and
> publicised by IANA, so that people wishing to make use of dtg defined
> resources know how to correctly address them?
> 
> Best regards,
> 
> Will Godfrey
> 
> 
> 
> 
> -----Original Message----- From: Peter Saint-Andre
> [mailto:[e-mail]] Sent: 20 April 2011 04:35 To: DTG
> Registration Cc: Benja Fallenstein; Ted Hardie; Dave Walton;
> [e-mail] Subject: Re: IANA URN registration enquiry -
> Rules for Lexical Equivalence of NSS part - Email found in subject
> 
> On 4/19/11 3:25 AM, DTG Registration wrote:
>> Hello,
>> 
>> When declaring rules for lexical equivalence of NSS part, is this 
>> section valid if only the URN NID is being registered with IANA?
> 
> I assume you're referring to Appendix A of RFC 3406. Because the
> entire text of that document is about the registration of a
> namespace identifier with IANA (or, to be precise, "the processes by
> which a collection of identifiers satisfying certain constraints can
> become a bona fide URN namespace by obtaining a NID"), it's not clear
> to me what you mean by your question "is this section valid if only
> the URN NID is being registered with IANA?" Only the NID is ever
> registered with IANA because specific URNs under that NID are issued
> by the administrative entity that registers the NID in the first
> place. However, part of the process of registering a NID is
> specifying the rules for lexical equivalence. As with the other
> requirements of RFC 3406, defining the rules for lexical equivalence
> will help the administrative entity to clarify its processes and
> procedures regarding URN issuance, and also will help developers of
> software for handling the issued URNs to implement consistent parsing
> algorithms.
> 
> Did I misunderstand your question?
> 
> Peter
> 
> -- Peter Saint-Andre https://stpeter.im/
>