OWL-S: Bringing Services to the Semantic Web

1. OWL-S:Bringing Services tothe Semantic Web David Martin SRI Internationalmartin@ai.sri.com http://www.daml.org/services/

2. These slides will be available here: www.daml.org/services/materials/swmu and will be linked from the SWMU Agenda page

3. Acknowledgements Material on “Why Semantic Web Services” and on “Commercial Web Services” borrowed from a ISWC 2002 tutorial presentation with kind permission from Dieter Fensel (U. of Innsbruck) & Christoff Bussler (Oracle)

4. Outline • Overview & Background • Why Semantic Web Services? • Commercial Web Services • WSDL, UDDI, SOAP, … • OWL-S Technical Overview • Profile, Process & Grounding ontologies • Next Steps & Future Directions • SWSI, SWSL & SWSA • Resources & Building Blocks • Applications, Tools, Components

5. Convergence on Services • Commercial vendors, media, forecasters, etc. • Intranets, not just internets • W3C Web services efforts • Semantic Web community • DAML-S/OWL-S; WSMF & other EU efforts • ISWC 2002: 10 services-related papers, 7 posters • Grid computing (OGSA) • Ubiquitous computing (devices) • Mobile access to services  A remarkable opportunity • Bringing behavioral intelligence to the Web

6. Why Semantic Web Services? Thanks to Dieter Fensel (U. of Innsbruck)for use of this material 500 million users more than 3 billion pages WWW URI, HTML, HTTP Static

7. Semantic Web RDF, RDF(S), OWL Why Semantic Web Services? Thanks to Dieter Fensel (U. of Innsbruck)for use of this material • Serious Problems in information • finding • extracting • representing • interpreting • and maintaining WWW URI, HTML, HTTP Static

8. Web Services UDDI, WSDL, SOAP Why Semantic Web Services? Thanks to Dieter Fensel (U. of Innsbruck)for use of this material Bringing the computer back as a device for computation Dynamic WWW Semantic Web URI, HTML, HTTP RDF, RDF(S), OWL Static

9. Intelligent Web Services Why Semantic Web Services? Thanks to Dieter Fensel (U. of Innsbruck)for use of this material Bringing the web to its full potential Web Services UDDI, WSDL, SOAP Dynamic WWW Semantic Web URI, HTML, HTTP RDF, RDF(S), OWL Static

10. Commercial Web Services: Definition “Web services are a new breed of Web application. They are self-contained, self-describing, modular applications that can be published, located, and invoked across the Web. Web services perform functions, which can be anything from simple requests to complicated business processes. … Once a Web service is deployed, other applications (and other Web services) can discover and invoke the deployed service.” IBM web service tutorial

11. Commercial Web Services:Business Vision • Business services can be completely decentralized and distributed over the Internet and accessed by a wide variety of communications devices. • The internet will become a global common platform where organizations and individuals communicate among each other to carry out various commercial activities and to provide value-added services. • Dynamic enterprise and dynamic value chains become achievable and possibly even mandatory for competitive advantage.

12. Commercial Web Services:Emerging Standards SOAP WSDL UDDI HTTP HTML URI

13. Commercial Web Services The web is organized around URIs, HTML, and HTTP. • URIs provide defined ids to refer to elements on the web, • HTML provides a standardized way to describe document structures (allowing browsers to render information for the human reader), and • HTTP defines a protocol to retrieve information from the web. ==> Not surprisingly, web services require a similar infrastructure around UDDI, WSDL, and SOAP.

14. Commercial Web Services • UDDI provides a mechanism for clients to find web services. • A UDDI registry is similar to a CORBA trader, or it can be thought of as a DNS service for business applications. • White pages: Who is the service provider? • Yellow pages: What is the service providing? • Green pages: How can I make use of the service?

15. Commercial Web Services • WSDL defines services as collections of network endpoints or ports. • The abstract definition of endpoints and messages is separated from their concrete network deployment or data format bindings. • The concrete protocol and data format specifications for a particular port type constitute a binding. • A port is defined by associating a network address with a binding; a collection of ports define a service.

16. Commercial Web Services • SOAP is a message layout specification that defines a uniform way of passing XML-encoded data. • In also defines a way to bind to HTTP as the underlying communication protocol. • SOAP is basically a technology to allow for “RPC over the web”.

17. Commercial Web Services:Basic Architecture Sweet Spot: Matchmaking From “Web Services Architecture W3C Working Draft”http://www.w3.org/TR/2002/WD-ws-arch-20021114/

18. Commercial Web Services:Summary • UDDI, WSDL, and SOAP are important steps into the direction of a web populated by services. • However, they only address part of the overall stack that needs to be available in order to achieve the above vision eventually. • Essentially, syntax and communication. • More is required to maximize reasoning & automation of Web service provision & use across the WS lifecycle • Development, discovery, selection, composition, monitoring, mediation, execution, monitoring & recovery, etc.