- From: <Patrick.Stickler@nokia.com>
- Date: Mon, 7 Jul 2003 10:33:49 +0300
- To: <uri@w3.org>
- Cc: <www-rdf-interest@w3.org>
Hi folks, The following is a proposal for an alternative solution meeting the goals of urn: URIs but with http: URIs so that the full richness of the web architecture can be exploited. (sincerest apologies to all the folks who have worked long and hard on DDDS... perhaps now to no avail) The combination of HTTP, PURLs, URIQA and a new top level domain make for a powerful solution that completely eliminates any need for the urn: URI scheme, or anything similar, as well as provides an immediate migratory path for all urn: schemes to http: URIs. The long term integrity of URN schemes are dependent on the longevity of the managing authority, though one would also hope that URNs would remain valid long after a given managing authority has ceased to exist and mint new URNs for that scheme. The greatest argument for urn: URIs over http: URIs is that (a) domain names do not last forever and and if the managing authority changes, the function and meaning of URIs grounded in that domain might change or become ambiguous; and (b) domain names reflect legal entities that one may not wish reflected in ones URI, if the denote resources that can be transferred to new owners. Well, this can be addressed with a very simple solution. I propose that a new top level domain .urn should be defined, managed by the same folks that manage the registration of urn: subschemes, whereby for any URN subscheme urn:X: there would rather be issued a subdomain X.urn. Then, the managing authority of that subdomain can mint http: URIs (URNs) based on that subdomain (regardless as to any services that might be offered by any web server operating in that subdomain). Thus rather than, e.g. urn:issn:1560-1560 you'd have something like http://issn.urn/1560-1560 and the need for solutions such as DDDS disappears, since HTTP now does the job quite nicely. The managing authority for the ISSN URN scheme could then host a server at http://issn.urn to provide access to representations and descriptions of the resources, or simply information about the owner of the URI -- or even nothing, which is no worse than present urn: URIs now. And since domains can be subdivided, and subpaths of URIs redirected to entirely different servers, the managing authority has a tremendous amount of flexibility in how it organizes its namespace and services provided for accessing representations and descriptions of the resources denoted by the URNs in question. A given managing authority could simply maintain a PURL like redirection service to customer-specific URIs, providing a consistent, opaque point of access to the resource that is nevertheless managed by the resource owner. E.g. if Example Inc. was issued ISSN 1560-1560, then an HTTP request to http://issn.urn/1560-1560 could be automatically redirected to http://example.com/issn/1560-1560 providing exactly the functionality that DDDS promises, but using the existing and proven web infrastructure. If Example Inc. later transferred ownership of that resource to e.g. Wombat Inc. then the redirection could be redefined to something like http://issn.wombat.org/1560-1560 etc. and agents would continue to interact with the resource in terms of its HTTP-URN transparently, with no manditory impact from the change in ownership. This solution also allows URIQA to be used for obtaining descriptions of such HTTP-URN denoted resources in a standardized manner, since in the same way as requests for representations would be redirected to the customer-specific servers, likewise, requests for descriptions would also be redirected. Note that the creation of the .urn top level domain is based purely on practical considerations, not technical ones, as this HTTP+PURL+URIQA approach will work equally well regardless of the domain name. Creating the top level domain .urn also allows for every URN subscheme now in existence to immediately be provided an HTTP resolvable namespace which has a regular transformation from the URN structure, allowing agents to work effectively with legacy content containing urn: URIs. Thus, the mapping urn:X:Y -> http://X.urn/Y becomes a poor-man's DDDS. And this approach likely has application to a number of other URI schemes as well... Simple. Eh? Cheers, Patrick -- Patrick Stickler Nokia, Finland patrick.stickler@nokia.com
Received on Monday, 7 July 2003 03:34:03 UTC