ADASS discussions

[Guy Rixon]

On Mon, 22 Sep 2003, Alasdair Allan wrote:
>
> I would certainly anticpate a "web service" stage before everyone moves on
> to full OGSA/OGSI grid services, I mean, alot of what we want to do doesn't
> need the complications of OGSI. Why make life difficult for people trying
> to access your service? It would be rather nice if you could talk to a
> service endpoint using straight SOAP as well as a full OGSI compliant
> toolkit if persistence isn't needed for your query...

Quite. I never expected to deploy dynamic grid services where stateless web
services would do the whole job.  I've been expecting to have a mixed
architecture with some OGSI services (e.g. AstroGrid mySpace) amongst ordinary
web-services.

Recently, I'm beginning to wonder if OGSI is worth the bother.  Here in Java
land, we're stuck with GT3 as the only implementation, which makes development
slow and difficult.  Parastatidis et al. have questioned the usefulness of
OGSI as a standard, proposing an alternative that matches better to web
services standards.  If we don't do OGSI now, I'm wondering if it will have
become obsolete by the time we need to exploit it.

AstroGrid's new tack is to be able to use OGSI services at the bottom of the
architecure, mainly as data-selection services.  E.g., we want to be able to
talk, via some gateway to be designed in detail next month, to an OGSA-DAI
instance as if it were one of the catalogue services in our data-access layer.
(Which is not yet the IVOA DAL, BTW.)  This puts us in the position of
wrapping grid services inside advanced web services.  We probably won't be
using OGSI at critical locations elsewhere in the architecture.

Guy Rixon 				        gtr at ast.cam.ac.uk
Institute of Astronomy   	                Tel: +44-1223-337542
Madingley Road, Cambridge, UK, CB3 0HA		Fax: +44-1223-337523