Re: Choreography and the Semantic Web

At 11:01 AM 8/12/2002 -0400, Mark Baker wrote:

>On Mon, Aug 12, 2002 at 09:45:38AM -0400, Christopher B Ferris wrote:
> >
> > Mark,
> >
> > And there is much that SOAP/WSDL do that RDF doesn't.
>
>Yes, but very little of it is necessary when you don't have a priori
>knowledge of the type of service you're interacting with, as the Web
>presumes.
>
>SOAP/WSDL, in common use, presupposes that when the code is written,
>it knows the difference between a thermometer and a television.  REST
>does not.

REST, may or may not. Programs and programmers, however do know what sort
of resources they understand, and to a much lesser extent, what sort of 
resources
they don't understand. (They have a very precise understanding of things 
they understand
and very little understanding of anything they don't understand.)

Programs don't start invoking services without context, nor without goals 
and specific
capabilities. At the end of the day, software can only couple up to the 
services and
resources it understands. A program attempting to determine the current 
temperature
in New York City is not only likely to understand what a thermometer is, it 
is unlikely
to want to talk to anything that *isn't* a thermometer. Ignoring, for the 
moment, how it
came to chose a specific URI to invoke, a program trying to interact with 
another chunk
of code is going to be able to do no more, and no less than what it is 
programmed to do.

- David


> > There is NOTHING that prevents one from using RDF in the context of Web
> > services technologies (e.g. carrying RDF graphs in the SOAP header or
> > body,
> > extending WSDL with RDF, or even representing a WSDL description using
> > RDF), or not as one sees fit.
>
>There's nothing that *prevents* RDF from being used with SOAP/WSDL, but
>as I said, the earlier form of binding with SOAP/WSDL makes RDF
>unnecessary (note, this is a *bad* thing 8-).
>
>MB
>--
>Mark Baker, CTO, Idokorro Mobile (formerly Planetfred)
>Ottawa, Ontario, CANADA.               distobj@acm.org
>http://www.markbaker.ca        http://www.idokorro.com

David W. Levine
IBM Thomas J. Watson Research Center
Autonomic Computing Tooling and Standards

Received on Monday, 12 August 2002 14:25:07 UTC