- From: David Booth <david@dbooth.org>
- Date: Wed, 17 Mar 2010 16:10:49 -0400
- To: Jonathan Rees <jar@creativecommons.org>
- Cc: www-tag@w3.org
Excellent summary! David On Wed, 2010-03-17 at 14:15 -0400, Jonathan Rees wrote: > AWWSW status (F2F prep) > > The AWWSW group was started because Alan Ruttenberg and I were doing > quite a bit of ontology design and ontology advising and didn't > understand the resource/representation relationship (and the > "information resource" idea, which is intimately bound up with it) > well enough to do our work or guide others. The question comes up > when you have things that you want to give a URI to, and you want to > use 200 responses (non-# non-303 URI), but want to be protected > against someone coming along later and saying "hey, that's not an > information resource," or "but you said it's an IR, and that implies > xxx" where you don't mean to say xxx, or "that's an IR, but not the one > you want it to be". > > This is dual (equivalent) to the question: Suppose you get 200 > responses, is it OK to then decide that the named resource > is some particular thing or has certain properties? E.g., if I am > the owner of dx.doi.org, can I say that the URI > http://dx.doi.org/10.1093/bib/bbn051 names the journal article > that's indicated in the representation (so that I can license others to use > the URI when recording metadata)? (Note that this is a subtle > example. The httpRange-14 rule by itself is not adequate to rule this in or > out. In particular the representation might fail to be "of" the > journal article even if we decide the journal article is an IR. Also > there is redirection involved, which complicates things further.) > > Alan and I approached the TAG, which said essentially "you figure it out." > (Shortly thereafter I discovered that I was on the TAG.) > > Some ontologies where this is an issue include FRBR, Dublin Core, > Bibo, SWAN, CiTO, IAO, and IRW, but as the practice of metadata > deployment, document and media annotation, etc. increases > (perhaps with the help of the Link: header?), I expect there to be > many more. > > A broader motivation, which I share with TimBL, is that if we had a > logical framework (perhaps expressible in RDF or OWL), we'd have a > tool that we could use to help clear up a number of number of web > architecture muddles. httpRange-14 is just an example; another > recent one on www-tag was "are HTML elements information > resources?" > > A third motivation is that an RDF vocabulary for webarch could be > useful in a number of application domains, e.g. testing and > validation, or recording change logs (e.g. Memento), or "HTTP over > SPARQL", or further developing Tim's generic resources ontology > (genont). > > Additional concerns have been raised in the group about how > URIs might become bound to things, but I have not pursued > this (yet). My current theory is that URI binding is a personal matter > subject to your belief set, and how you come to that is your > own business. You may choose to let what happens on the > Web influence your beliefs, and there may be a recommended > elective way to allow this to happen, and > perhaps an outcome of this project, in the future, might be > such a way. > > I can't say we've made a lot of visible progress, but I think I do > understand the problem better now that I did before. > > First, Roy Fielding is right: We're not just talking about HTTP > semantics, but rather the semantics of that part of web architecture > that is expressible in HTTP. This includes the > resource/representation relationship, the various redirects (including > 303), and possibly existence (creation and deletion). I think webarch > as deployed might include REST as a subset, but certainly there are > resources deployed using GET+200 that do not obey REST discipline, and > we need to account for these somehow. > > Second, TimBL has provided more information about his view of what is > and isn't an information resource, and he thinks they're like. I have > been unable so far (my > inadequacy) to combine these use cases with other constraints (such as > grandfathering all possible web pages) into an actionable definition > that makes sense to me, but I continue to work at it. > > Third, "authoritative" per the updated http: URI scheme in HTTPbis is, > I think, orthogonal to the R/R problem. The "authoritative" responses > do not determine the resource uniquely, they only say that it belongs > to a class of resources that participate in the R/R relationships > communicated by the responses. A contradiction between an > "authoritative" response and other information believed about the > resource might lead you to discount the "authoritative" response (as > recommended by the GBIF persistent identifiers report) or to > stop using that URI to name the resource, just as easily as it might > lead you to doubt what you thought you knew about the resource. > > Of course, the ability of an agent to speak HTTP-authoritatively about > a resource may be due to the agent's ability to control the resource > and therefore its "representations". For these particular resources, > the R/R relationship holds because the agent says so. For others > (such as Moby Dick) it might hold in spite of what the agent says. > > I am concentrating on the resource/representation relationship. My > ambition is that if we have a story about when this holds and doesn't > hold - in particular how to falsify it - then answering the > question "what is an information resource" will fall out as a side > effect: an IR is simply something which happens to be able to > participate in this relationship. > > So far the best lead I've encountered so far in understanding the > relationship is ABLP logic, as is being pursued by Dan Connolly. It > may be that ABLP can't be used directly, as convincing someone that a > web page is a principal, or that "principal" has any ontological > consequence, might be a tough sell. Or it may be that this, too, is > an ontological wild goose chase, or that ABLP is about > the URI/resource relationship instead of the resource/representation > relationship. But it's worth pursuing. > > Open issues on which these considerations impinge: > ISSUE-50 URNs and registries - persistence vs. trust in "authority" > ISSUE-57 HTTP redirections - consequences of 30x > ISSUE-63 metadata architecture - metadata for http:-named resources > ISSUE-53 generic resources (appears to be closeable) > > Next step (for me): Look in more detail at the kinds of metadata, > including class memberships, one might want to write using the > abovementioned ontologies for some sample resources, > and attempt to generalize from there. > > I'll try to have slideware ready in time for the F2F. > > Thanks to Michael Hausenblas and David Booth for their help. > This email is in the first person because they haven't > seen it to agree with it or not, but I am happy to expand > "I" to "we" for anything they want to take credit for above. > Thanks also to many others including Alan, Tim, Harry Halpin, > Stuart Williams, and Noah for their contributions. > > Jonathan > > too pressed for time to look up URIs for all the things cited. here > are the obscurest ones: > memento: http://www.readwriteweb.com/archives/memento_protocol-based_time_travel_for_the_web.php > gbif: http://www2.gbif.org/Persistent-Identifiers.pdf > iao: http://code.google.com/p/information-artifact-ontology/ > genont: www.w3.org/DesignIssues/Generic.html > the others you should be able to get from google or tracker. > > > -- David Booth, Ph.D. Cleveland Clinic (contractor) Opinions expressed herein are those of the author and do not necessarily reflect those of Cleveland Clinic.
Received on Wednesday, 17 March 2010 20:11:18 UTC