RE: FWD [Work in Progress on Semantics for Web Services (Advance Notice)]

Dear Dr. Bournez:

I joined this working group and mailing list but cannot add my comments into
the archive. Maybe my opinion is not welcome but I hope more and more people
can understand what' wrong for those research approaches on semantic Web
services research when they are used in real world development. I think I
contacted you and many other W3C staffs, directors and writers of OWL-S,
WSMO, WSDL-S. I hope people in this working group will not keep silence on
those known problems.

In my opinion, the mechanism of OWL-S looks like a backward-engineering
process. Since WSDL is the outcome of OOP, then what OWL-S can do is only
restore the object hierarchy and relationship in the development process of
OOP. In this way, every object used in the Web services can be associated
with others under such framework but OWL-S cannot describe the meaning of
the objects used in the OOP. 

WSDL-S makes things worse since it only “adds” semantics onto certain
objects while remains the others undefined, that is to say, given the
example of Address Finder Web Service (URL can be accessed at:
http://arcweb.esri.com/services/v2/AddressFinder.wsdl ), WSDL-S would only
add semantics onto such WSDL elements like street, intersection, city,
state_prov, zone, country, user name, password, but ignore the other
elements such LocationInfo, ArrayOfLocation, Location[], description1,
description2, addressFinderOptions, token, matchType, etc. just because they
are not meaningful. Thus the whole WSDL file will be a mess for requesters
to understand and use. 

WSMO creates a conceptual model to describe the meaning of the service and
probably can be a useful approach to develop semantic Web services.
Unfortunately, WSMO by now has to “ground” to WSDL to connect both systems
together and to derive the service semantics. If WSDL is NOT the appropriate
source from which to derive data and service semantics, WSMO just associates
with a wrong object and thus cannot get the correct result. Thus if there is
no way to “ground” to WSDL, WSMO is useless as a stand-alone framework.

In conclusion, the source of the problem in their research on semantic Web
services is that researchers just used some simple business transaction
models and then the whole process is simplified. That is to say, all WSDL
elements used in such simple models are intuitive and self-understandable.
However, given the example in Address Finder Web Service, most of WSDL
elements are meaningless, redundant, and irrelevant to the users to set up a
direct relation between the input variables and output results. When we try
to use such real-life cases to test those mechanisms, then we can find the
true problems. I tried to CMU's WSDL2OWLS tool to convert the WSDL file of
Address Finder Web Service into OWL-S, the result is almost meaningless and
users still cannot understand the meaning of the service. Unfortunately,
CMU's Web site for testing their tool is down and maybe they just knew OWL-S
approach cannot solve the problem.

What's the semantics for Address Finder Web Service? The direct and explicit
meaning of this Web service is: if the user can provide user name, password,
and address information on street, city, state (or province), zip/post code,
then the service will return the location of the input address.

I suggest that researchers should give up dealing with those simple business
transaction models. I know SWS now is a big "business" but please test your
approaches and see if your approach can describe the meaning of "Address
Finder Web Service". If it fails, you have to consider what's wrong and
reformat your approach. Don't tell people that your approach can work find
with credit card transaction, buy book, ticket, purchase order, etc. etc....
They are just meaningless in the real world.

Any comments and suggestions will be greatly appreciated. I hope W3C and SWS
committee members will not keep silence any more to this challenge since
many of them already knew the content of this message for a rather long
time. I look forward to hearing from you.

Best wishes,

Xuan



-----Original Message-----
From: Carine Bournez
To: Battle, Steven Andrew
Cc: public-sws-ig@w3.org
Sent: 9/1/05 6:11 AM
Subject: Re: FWD [Work in Progress on Semantics for Web Services (Advance
Notice)]


On Thu, Sep 01, 2005 at 10:50:47AM +0100, Battle, Steven Andrew wrote:
> 
> Carine,
> Can you shed any light on the decision here to establish a charter for
a
> new working group rather than - or perhaps in addition to - a lighter
> weight incubator activity. The attendee poll at the FSWS workshop
found
> little enthusiasm for such a working group. What caused this shift in
> opinion at the W3C?
> Steve.

Steve, all,

This "Advance Notice" is precisely aiming at gathering feedback about
the
way to go. W3C Members are aware of lightweight process and should react
on member-ws@w3.org about this process.
Thank you for raising this point.

Received on Thursday, 1 September 2005 12:55:21 UTC