Re: [urn] Thread about urnbis-semantics-clarif-03 in the context of updating 3986

[Andrew Newton <[e-mail]>]

On Tue, May 31, 2016 at 4:32 PM, Sean Leonard <[e-mail]> wrote:
> This is a thread about urnbis-semantics-clarif-03 in the context of updating
> RFC 3986, as requested.
>
> draft-ietf-urnbis-semantics-clarif-03 originally started out as (John's)
> polemic against using the URI framework ("syntax and high-level semantics of
> URLs" -- see draft-ietf-urnbis-urns-are-not-uris-00 Section 1) for URNs.
> That draft has a Section 3, which states:

The definition of "polemic" is: a strong verbal or written attack on
someone or something.
The key words being "strong" and "attack" which connote discourse not
becoming of the IETF. I believe this is a mischaracterization of both
John and his work. Let's try to avoid such words in the future.

> That verbal formulation (including the typo...) has survived through the
> drafts into Section 4 of draft-ietf-urnbis-semantics-clarif-03.
>
> Other stuff that purports to get updated: stuff about queries; stuff about
> fragments; and...that's about it. Oh, it also says stuff about how RFC 3401
> and RFC 2483 apply but don't apply and we aren't talking about them.

The references to 2483 and 3401 are in regard to scope of the changes
and seem completely appropriate.

>
> ******
>
> Overall, the problems that need to be addressed are:
>
> draft-ietf-urnbis-semantics-clarif-03 doesn't actually *do anything*. I view
> it as a lot of hot air...either that hot air gets into 2141bis, or blow it
> away. I see nothing implementable here in Internet software or protocols.

"hot air"... again, let's dial it down.

> Julian just re-posted his April 27 message, with quotations from the specs.
> As pointed out, URIs don't have semantic requirements in the ways that
> clarif-03 worries about. This is focusing on the query and fragment
> productions. Specifically, RFC 3986 says:
>
> "If no such representation [a content, including a media type] exists, then
> the semantics of the fragment are considered unknown and are effectively
> unconstrained. Fragment identifier semantics are independent of the URI
> scheme and thus cannot be redefined by scheme specifications."

The entirety of that paragraph is:

   The semantics of a fragment identifier are defined by the set of
   representations that might result from a retrieval action on the
   primary resource.  The fragment's format and resolution is therefore
   dependent on the media type [RFC2046] of a potentially retrieved
   representation, even though such a retrieval is only performed if the
   URI is dereferenced.  If no such representation exists, then the
   semantics of the fragment are considered unknown and are effectively
   unconstrained.  Fragment identifier semantics are independent of the
   URI scheme and thus cannot be redefined by scheme specifications.


As I recall, the issue was that fragments could not be defined by a
URN namespace thus causing the basis for separation of syntax from
semantics.

-andy