ACTION-282 = Draft a finding on metadata architecture

Jonathan Rees, 2 December 2009

Not ready to draft a finding because:

  1. I need a clearer idea of what needs to be said and why
  2. I need to do more research (tracking down examples and analyzing them) - in particular, nearly every bullet point below needs some thought and at least one example

Here are some thoughts on organizing these two tasks.

Why should the TAG get into this?

Why should the TAG care about metadata?

What is the division of responsibility between TAG and others (e.g. W3C working groups)?

What could we possibly do? We're not a WG.


In more or less chronological order:

  1. Metadata on the Web: A survey Feb 2009
  2. Discussion of first-party-provided metadata (as opposed to metadata from other sources). This has mostly fallen under ISSUE-62 (303, LRDD)
  3. Larry Masinter email on July 21 announcing ISSUE-63: Metadata Architecture for the Web, closing ACTION-254. This frames the issue, saying what the components of any metadata architecture ought to be.
  4. Steve Rowat's writings:
    1. US patent 6782394 "Representing object metadata in a relational database system"
    2. email to www-tag 21 August "Goals of a W3C-mediated Global Metadata System"
    3. email to www-tag 21 Sep "Ten Use-Cases of Individual Content Authors Requiring Rights/Commerce Metadata"
    I found these to be interesting as they raise the issue of attaching metadata to resource parts such as sections, passages, tracks, time intervals. This relates to RDFa which (among other things) supports metadata reffering to parts of XHTML documents (I believe!? - verify this), and our previous discussion of URIs for video segments.
  5. Metadata-as-deployed thread started by Dan


For further research:

Does metadata have any special role on the web (as compared to other kinds of content)?

Yes, metadata makes the data (and therefore the Web) more valuable in particular ways that both promote interoperability and benefit from it.

Is there a problem? In what ways is metadata on the web less webby (connected, open, inclusive) than it ought to be?

Not enough of it (example?) - poor incentives for creating it

Difficult to deploy

Hard to validate

A lot of what's there is closed, e.g.

Difficult to use at scale

Being a master consumer of metadata is complicated (XMP, GIF, <link>, LRDD, 303, RDFa, ...)

Doubt and uncertainty regarding data identity

Unclear lines of authority, thus difficult to evaluate for trustworthiness (but how is this different from any other content on the web?)

How to consistently identify people, organizations, places (organize bookmarks by author, photos by place)

What metadata do we care about?

Is there such a thing as data that is not metadata? Metadata that is not data? Can non-data have metadata? If X is about Y, does that mean X is in scope of this project, or is X only in scope when Y is data?

Are OpenID and XRD a metadata use case, or just application-related data?

Is RDF nose-following (linked data) a metadata use case, a world unto itself, or an intersecting world?

Should we focus our attention on particular metadata profiles (e.g. Dublin Core), or on the meta-metadata problem (bibliographic would be a special case, offers to sell might another, audio another, etc.)?

Is "metadata" even the right word to cover this project?

What deployments / use cases are inspirational?

Both private and public, that is. Figure out business models, especially for the more public sources.

What potential technical opportunities are there?

Things someone might do in RDF-land to advance web metadata:


Does "metadata architecture" make sense? Is it something to be discovered (empirical), designed (invented), or some of each?

Is anything different now compared to 10 years ago when RDF and Dublin Core were published?

The Metadata Activity Statement (1998) is worth a look.