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A. Dogac. Grenoble Ecole de Management MEDFORIST Workshop. 2/14. Why do we need Web Service Semantics?. In order to exploit services in their full potential their properties must be defined:The methods of charging and paymentThe channels by which the service is requested and providedConstraints
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1. A. Dogac Grenoble Ecole de Management MEDFORIST Workshop 1 Semantics of Web Services Asuman Dogac
Middle East Technical University
Software R&D Center
Ankara, Trkiye
2. A. Dogac Grenoble Ecole de Management MEDFORIST Workshop 2/14 Why do we need Web Service Semantics? In order to exploit services in their full potential their properties must be defined:
The methods of charging and payment
The channels by which the service is requested and provided
Constraints on temporal and spatial aspects
Availability
Service quality
Security, trust and rights attached to a service
3. A. Dogac Grenoble Ecole de Management MEDFORIST Workshop 3/14 Why do we need Web Service Semantics? To be able to describe service properties
and later search for services according to their properties
This search needs to be done in a machine processable and interoperable manner
This in turn is possible only by describing the semantics of Web services through ontology languages
4. A. Dogac Grenoble Ecole de Management MEDFORIST Workshop 4/14 WSDL does not describe Web service semantics
5. A. Dogac Grenoble Ecole de Management MEDFORIST Workshop 5/14 Taxonomies are not enough to define service semantics:An Example Taxonomy: UNSPSC
6. A. Dogac Grenoble Ecole de Management MEDFORIST Workshop 6/14 An Example Ontology for Travel Domain
7. A. Dogac Grenoble Ecole de Management MEDFORIST Workshop 7/14 Properties of ReserveAFlight Generic Service
8. A. Dogac Grenoble Ecole de Management MEDFORIST Workshop 8/14 Ontology Languages Resource Description Framework
DAML+OIL by
DARPA and
On-To-Knowledge project (European Commission, IST-1999-10132)
Extends RDF with more sophisticated class and property definitions
OWL (Web Ontology Language) by W3C
Based on DAML+OIL
DAML-S by DAML Services Coalition
9. A. Dogac Grenoble Ecole de Management MEDFORIST Workshop 9/14 Ontology Languages Have formal specification and thus can be queried
Provide the means to define sophisticated class properties
10. A. Dogac Grenoble Ecole de Management MEDFORIST Workshop 10/14 DAML-S
11. A. Dogac Grenoble Ecole de Management MEDFORIST Workshop 11/14 How do we define and use service semantics? There are two key issues:
Where to store the generic semantics of the services
How to associate the ontology classes with the services advertised?
12. A. Dogac Grenoble Ecole de Management MEDFORIST Workshop 12/14 Where to store the service ontologies? UDDI does not provide an internal mechanism to store generic service semantics
ebXML, on the other hand, through its classification hierarchy mechanism allows domain specific ontologies to be stored in the registries
13. A. Dogac Grenoble Ecole de Management MEDFORIST Workshop 13/14 DAML-S ServiceProfile Class Some of the properties of ServiceProfile class are:
parameter property
For example, a subproperty is input, another output
serviceParameters, subproperties of which may be max response time, geographicRadius,
serviceType, high level classification of service such as B2B or B2C
serviceCategory, refers to an ontology of services
And more
14. A. Dogac Grenoble Ecole de Management MEDFORIST Workshop 14/14 DAML-S Provides an upper ontology, that is, defines a class called Service
It is necessary to define the lower levels, i.e, domain specific ontologies
Grounding them in upper ontologies like DAML-S makes them
more consistent and
interoperable