Applications Messaging Standard

[Doug Tody]

I think we are talking about two different things here.  The VO registry
would be used to discover applications or services available somewhere
on the Internet; the scope is world wide.  A "message bus" on the other
hand (PLASTIC is a simple version of one), registers connected apps for
a desktop session.  The types of apps used in a desktop session often
would not be available as services via the Internet (but they might
still be described in the VO registry just so that one can find out
about them).  The "hub" or message bus type of registry is more a type
of naming service.

On the issue of using files to store/exchange metadata: this is just
too problematic for a distributed system (except maybe for simple
startup stuff).  Messaging is often used to link together modules in a
distributed system, and this may well span multiple computers.  Files
may not be visible from all participating nodes, plus there can be
synchronization, caching, and platform issues.  Best to avoid files
except perhaps for startup on the login/head node.

	- Doug


On Mon, 12 Feb 2007, John Taylor wrote:

> Hi Bob - thanks for that link.  Yes, I do remember the discussion
> getting a bit bogged down with issues such as whether the cost of the
> software ought to go in the registry entry.
>
>
>
> On 12 Feb 2007, at 20:32, Robert Hanisch wrote:
>
> >>
> >>
> >> You seem to be thinking about getting app metadata out of an IVOA
> >> registry.  This is something we haven't done: the Hub only knows
> >> about applications that are currently running.  I think this is an
> >> idea well worth exploring.
> >
> > We started discussing applications metadata and adding it into the
> > registry about two years ago, but the effort has kind of stalled.
> > There are some notes from the Madrid Interop meeting that are
> > relevant ( http://www.ivoa.net/twiki/bin/view/IVOA/
> > InterOpOct2005ResReg), and at the bottom of this page you will see
> > a link to ApplicationsSoftwareMetadata.pdf.  I am curious whether
> > this is the kind of information of interest, or if this information
> > can be augmented to support the messaging needs.
> >
> > Bob
> >>>
> >>>
> >>
> >>
> >
>
>