Comments about URI/URL/URN definitions going forward

I was asked by members of the Web and TV IG to post this comment to the public list, so here it is.

Thanks!
-Paul

Paul Gausman, Service Architect
Architecture and Engineering
AT&T Services

_____________________________________________
From: GAUSMAN, PAUL
Sent: Wednesday, February 11, 2015 12:03 PM

There was a question about the definition of URI and URN (and perhaps URL). Here's my 2 cents:

I would like to think of a URN as an entity identifier, preferably a unique one. I don't think it is practical or necessary for all entities to be uniquely identified but I think it is important for any entity that requires authentication, e.g. a commercial/licensed content asset or a subscription service.

I think of a URI as a complete address to an entity, including protocol, host, path and URN (as defined above). So you see, I think of a the last segment of a web path (i.e. URI) as being a URN. However, there are many other places that one could use or find a URN, such as a catalog, etc.

A URL would be the path to an entity from the host part through all path indicators up to but not including the last segment, which contains the URN. A URL (or URI) can arguably contain the protocol, user ID/password and port, or not.

Of course there is the possibility of a URL (i.e. location) not taking a standard web address format. The important thing is that it is the location which pertains to the URN in question.

I'm thinking that things like Content Centric Networking (CCN) may have a major impact on what can be considered a URL, URI and URN. Handling of content level URNs and asset level URNs in a CCN context will likely also have an impact on these definitions. (Use of CCN addressing and networking functions could be very beneficial to commercial content owners and providers in reducing misuse of content and efficiency of distribution.)

Lastly, I would like to add that in my view, every entity in the digital services space are potentially "content", in that I would define content as any digital entity which is offered or requested as content by another digital entity. So, AAA security, DRM and other functions which previously have pertained narrowly to a process/service, user, media asset, etc., is potentially applicable to any entity. Therefore, the ideas of URN, URI and URL should be capable of pertaining to any digital entity, dependent on the role that the entity is engaged in (e.g. content, meta-content, consumer, producer, etc.)

Thanks!

-Paul