RE: potential users of web services

Thomi,

I would agree with most of what Anne says (especially the part about
there being no clear definition of web services).  The one part I would
disagree with is that UI should be separate from web services.  It is
certainly true that today, neither ASP pages or HTML forms are web
services.  In the current world, the UI is always the end of the chain.
However, there is some work taking place that aims to change this.

There is an OASIS TC called "Web Services for Interactive Applications"
(WSIA) whose goal is to allow web services to deliver their own UI along
with the functionality they provide.  Here is a link to the TC's web site
where you can get more info http://www.oasis-open.org/committees/wsia/.

To expand on Anne's example below, lets suppose that someone wants
to take the catering application and use it as part of an application that
helps plan corporate events.  One option would be for me to use the
same services as the catering application and rebuild all the logic that
connects them together and creates the UI.  For simple examples, the
cost of this is low; but in many cases it means that I'm going to be
replicating a lot of work that has already been done.  It would be much
better if I could treat the catering application (including its UI) as a
service that I could reuse.  Of course I would need the ability to adapt
this service so it fits in my new application.  This is part of what the
WSIA is addressing.

IMO, this kind of multi-level chain, where each party can add their own
unique value (including UI) is going to be necessary if web services are
to reach their full potential.

Anyway, check out the WSIA site if you interested in some more info
on this.

Sean Fitts
CTO, CrossWeave

At 02:04 PM 4/4/2002 -0500, Anne Thomas Manes wrote:
>Thomi,
>
>Ask five people the definition of "web service" and you'll get six answers.
>
>I generally describe a web service as a service that communicates over the
>web. A service is a component that exposes a programmatic interface. The
>service interface must be described; and the service implementation must be
>discoverable.
>
>When you relate this abstract definition to current technologies, you can
>implement a web service by creating a service that exposes a SOAP interface,
>which is described by WSDL, and which is registered in UDDI. But I wouldn't
>want to use current technologies to *define* the basic concept. I also don't
>think that it's essential to use any of these technologies to create a web
>service. I can certainly create a web service using XML-RPC or RosettaNet or
>a host of other technologies.
>
>That said, I would concur that web services are intended to be consumed by
>applications rather than humans. But keep in mind that a user interface is
>an application. If I wanted to arrange food for 500 people for two weeks in
>Dubai, I would use a catering application, which in turn uses web services
>to find caterers that can provide services in Dubai. The UI isn't the web
>service. The UI uses web services to accomplish its work. Hence an ASP page
>or HTML form aren't web services, they are an interface to web services.
>
>Best regards,
>
>Anne Thomas Manes
>CTO, Systinet
>
> > -----Original Message-----
> > From: www-ws-request@w3.org [mailto:www-ws-request@w3.org]On
> > Behalf Of Thomi Pilioura
> > Sent: Thursday, April 04, 2002 9:09 AM
> > To: www-ws@w3.org
> > Subject: potential users of web services
> >
> >
> > Hi all,
> >
> > I'm little confused about the notion of the term "web services".
> > When I'm reading papers related to UDDI,WSDL,SOAP they present
> > web services
> > as a new age of distributed computing and as such they are only useful to
> > developers (who are trying to build web applicattions) and not to the
> > end-users. But when I'm reading papers related to DAML-S the idea I'm
> > getting for web services is different. They are also useful to
> > end users as
> > it shown by DAML-S motivating scenarios:
> >
> > Web service discovery
> > Find me a shipping service that transports goods to Dubai.
> >
> > Web service invocation
> > Buy me 500 lbs. powdered milk from www.acmemoo.com
> >
> > Web service selection, composition and interoperation
> > Arrange food for 500 people for 2 weeks in Dubai.
> >
> > Web service execution monitoring
> > Has the powdered milk been ordered and paid for yet?
> >
> > There are also numerous papers that use the term service (and not "web
> > service") and are talking about UDDI, WSDL and DAML-S. What's the
> > difference
> > between "web service" and "service" if both of them work over
> > Internet? For
> > example, a search engine (such as google) is a service, but when it is
> > described in WSDL, published in UDDI and can be invoked using
> > SOAP becomes a
> > web service? Ia a asp or an HTML form a service or a web service?
> >
> > In summary which are the potential users of web services (web service
> > providers, developers, end-users)?
> >
> > could you please shed some light on this?
> > regards
> > Thomi Pilioura
> >
> >
> >
> >

Received on Thursday, 4 April 2002 15:08:55 UTC