- From: Hammond, Tony (ELSLON) <T.Hammond@elsevier.com>
- Date: Fri, 17 Oct 2003 11:20:34 +0100
- To: 'Larry Masinter' <LMM@acm.org>, 'Graham Klyne' <GK@ninebynine.org>, 'Gustaf Liljegren' <gustaf.liljegren@bredband.net>, uri@w3.org
> Let us imagine a policy where namespaces that have (interesting, useful) > operational definitions get to be registered as URI schemes, namespaces > that have a definition which establishes a (possibly delegated) > naming authority / registration mechanism get to be registered as > URN namespaces... Allowing for the plausibility of the concept of URN (which becomes somewhat problematic if the concept of URL is suddenly deprecated), then it must be asserted that URN could be applied to multiple URI schemes and not just pegged to a single URI scheme that so happens to call itself 'urn'. That would be to introduce a point of gross non-uniformity into a system of resource identification that champions its uniformity. However, my personal view is that while I understand that the IANA would like to keep everything nice and tidy and ship-shape and to distinguish names from addresses, the reality is quite simply otherwise. The horse has truly bolted (and been gone some time now I might add). It would appear to be too late to retrofit these conceptual categorizations onto the URI continuum. RDF and XML Namespaces, as two URI applications among others, have fully put paid to that. There is also a view that the 'cost of introduction of new URI schemes is high'. I would take exception with this, and note that this view presumably arises from the common expectation that URI schemes are necessarily dereferencable and that transport protocols need to be supported. This is not the case. The 'info' URI scheme, for one, expressly excludes dereference for simplicity's sake. So what cost then to a URI processor? If it is aware of certain URI schemes and the operations that can be performed upon those URIs (e.g. retrieval), then fine. Otherwise it can profitably recognize a URI for what it is in a given URI context and reliably use that for identity purposes. There is another aspect to this. Are the number of URN namespaces to be likewise restricted? Or can they be allowed to multiply since evidently they are apparently not 'interesting' or 'useful'. In short, are such namespaces to be considered the lumpenproletariat of the URI world? > ... and namespaces that have neither get to be debated endlessly > on uri@w3.org, until the definers give up or else fit their schemes > into one of the two camps. By 'give up' I expect this is intended to refer to registration under the IANA. The authors of the 'info' URI scheme already have existing applications that will make good use of the 'info' URI scheme and have no intention to 'give up'. (I assume BTW that the 'two camps' reference is to 'urn' URIs and not-'urn' URIs. Bit of an odd carve-up of the URI terrain. But that's just a personal opinion.) Tony Tony Hammond Advanced Technology Group, Elsevier 32 Jamestown Road, London NW1 7BY, UK <tel:+44-20-7424-4445> <mailto:t.hammond@elsevier.com>
Received on Friday, 17 October 2003 06:21:27 UTC