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“Where is My Service, Dude?“ How Semantics Solves and Makes Problems. Muhammad Fadlisyah ASNA PhD-Day Enschede, 09 June 2006. Contents. Discovery in Web services. Discovery in Semantic Web Services. Web services.
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“Where is My Service, Dude?“How Semantics Solves and Makes Problems Muhammad Fadlisyah ASNA PhD-Day Enschede, 09 June 2006
Contents • Discovery in Web services. • Discovery in Semantic Web Services.
Web services • Aspects of communication and interaction between Service Provider and Service Requester in Web services: • Activities • Service description • Implementation architecture
Web services • Aspects of communication and interaction between Service Provider and Service Requester in Web services: • Activities • Service description • Implementation architecture Publishing, discovery, selection, execution, composition, contract agreement
Web services • Aspects of communication and interaction between Service Provider and Service Requester in Web services: • Activities • Service description • Implementation architecture Architectural type(Broker, matchmaker, P2P), resource management, etc.
Web services Automated • Special interest: to support dynamic reconfiguration of services.
Discovery in Web services • Discovery: matching service request – service offer. • Service description: using WSDL (Web Service Description Language).
Discovery in Web services • Example: flight_reservation.wsdl
Discovery in Web services • Example: flight_reservation.wsdl
Discovery in Web services • Using WSDL,syntactical matching: • Keyword based search • Type based matchers • Problem: Automated discovery (to support automated composition): limited. • To support automated discovery: • Need to know meanings of inputs/outputs. • Need to know preconditions and postconditions. • Need to know the relation among operations and messages.
Semantic Web Services • Semantics: to increase level of automation. • Provider and Requester share same semantics.
Semantic Web Services • Service description: • Functionality: precondition (input,assumption), postcondition (output,effect) . • Non-functionality • Behaviour: sequences of operations.
Discovery in Semantic Web Services Discovery in SWS (3 approaches): • Matching based on semantic information. • Matching based on relationship among functionality elements: precondition (input, assumption), postcondition (output, effect) [1]. • Matching based behavior [3].
Discovery in Semantic Web Services • Semantic matching between service request and service offer: set-based modeling (appr. 1 and 2) [1].
Semantics Interop. Problems and Discovery • SWS Problem: not share same semantics (semantics interoperability problem, SIP). x
Service Description • Solutions to SIP? Semantics mapping. • How the solutions are decribed in Service Description? In Implementation Architecture?
Service Description Problems in service discovery • Identify the SIP: before or after matchmaking? • How to find the solutions or mapping?
Discovery in Semantic Web Services • Existing SWS Conceptual Frameworks
Discovery in Semantic Web Services • Notes: • OWL-S: Ontology Web Language-Service • WSMO: Web Service Modeling Language • SWSO: Semantic Web Services Ontology • DSD: DIANE Service Description (Uni Jena and Karlsruhe) • WSDL-S: Web Service Description Language-Service
References • WSMO Web Service Discovery, D5.1 v0.1, Keller et al., 2004 • Semantic matching of Web service capabilities, Paolucci et al. 2002 • Web service discovery based on behavior signatures, Shen and Su, 2005 • Web Service Semantics-WSDL-S, Akkiraju et al. • Semantic Web Services Ontology, Battle, 2005 • What is needed for Semantic Service Descriptions? A Proposal for Suitable Lagugae Constructs, Klein et al.