W3C home > Mailing lists > Public > public-ws-chor@w3.org > May 2003

service type and the Semantic Web

From: Stanislaw Ambroszkiewicz <sambrosz@IPIPAN.Waw.PL>
Date: Tue, 6 May 2003 19:18:22 +0200 (MET DST)
To: public-ws-chor@w3.org
Cc: Stanislaw Ambroszkiewicz <sambrosz@IPIPAN.Waw.PL>
Message-ID: <Pine.GSO.4.44.0305061913090.9688-100000@wars.ipipan.waw.pl>

 >> Jon Dart wrote:
> >> So service type is just a more generic term and a WSDL interface is
> >> just part of the definition of that type.

Consider two services; each of them performs one operation.
Suppose that input data types of the two services are the same as well
as the output data types.
Is it possible that these services perform different operations?

If the answer is NO, then service type is hard-coded in the input and
output data types.
It means that the pair of input and output data types determines the
type of service.
It is a solution to the problem of service type.
The solution is of particular interest for procedural (imperative)
approach to service composition, like BPEL.
Then, the type of composite service as well as the interface can be
created automatically from BPEL code.
Please note that if the service type (proposed by Sanjiva Weerawarna)
had been included in WSDL 1.2,
then it would be hard or even impossible to create the interface of
composite service automatically.
If I am not right, please let me know it.

If the answer is YES, then it is clear that the service type is
necessary, and there must be another means to express the type of
service. The solution proposed by Sanjiva Weerawarna seems to be
insufficient, i.e., something more is needed than just giving a name to
a service type.
IMO the concept of service type is related to the more fundamental
concept of meaning on the Web.
However, it seems that DAML-S did not succeed in achieving its ambitious
goal; it was reduced more or less to WSDL + UDDI + BPEL.
Perhaps it is the high time to come back to the roots of the Semantic Web.

Best regards,
Stanislaw
---
Stanislaw Ambroszkiewicz
Polish Academy of Sciences          http://www.ipipan.waw.pl/mas/
Received on Tuesday, 6 May 2003 13:25:49 GMT

This archive was generated by hypermail 2.2.0+W3C-0.50 : Saturday, 18 December 2010 01:00:17 GMT