xml-dev - Microsoft's DISCO proposal and XML packaging

[Edd Dumbill <edd@usefulinc.com>]

I've just read http://msdn.microsoft.com/xml/general/disco.asp
"Draft: Discovery of Web Services (DISCO)"

Some thoughts immediately spring to mind, and most of them center around
the uneasy feeling that wheels are being reinvented. For this reason
I'd like to draw the attention of the list to the draft and get some
opinions on it.  Unfortunately, the authors aren't named on the document
itself. I have a couple of nits, which I'll mention here, but the second
half of this message contains what I view to be the more important
thoughts that DISCO provokes.

* the proposals for embedding metadata etc. seem rather similar to RDF.
  Any comments on why RDF is not used here?

* the mechanisms for finding the discovery documents over HTTP seem a
  little odd to me (eg. putting a discovery document in a stylesheet).
  I'm certainly no expert in this domain, which is another reason I'm
  inviting comment.

This work seems to have overlap with various proposals and ideas
circulating about scraping RDF out of web documents and so forth, as
well as P3P policy discovery, robots.txt successors etc. etc. It
would be nice to draw these efforts together, as Microsoft certainly
seem to have a concrete application here for some of the experimental
work done so far.

I will also note that DISCO seems close to Sean McGrath's XFM (XML
Feature Manifest) and Simon St.Laurent's XPDL
<http://purl.oclc.org/NET/xpdl>.  I asked at WWW9 about W3C
initiatives for addressing this kind of "packaging" activity, and got
the response that it was effectively on hold and nothing was happening
on it

I think many of us who would like to see a rise in the provision and
usage of web metadata, as well as the pursuit of XML packaging, would
appreciate as few disparate initiatives as possible. So, to summarize
what I'm asking:

(a) what do people think of this proposal
(b) should it be part of some larger activity
(c) ... and is that activity connected with XML "packaging" aka
    document profiling

Tim Bray introduces the issues around resource discovery in
<http://www.textuality.com/xml/why-pkg.html>

-- Edd