David Martin for DAML-S Coalition 05/08/2003 OWL-S: Bringing Services to the Semantic Web David Martin SRI International [email protected]

David Martin for DAML-S Coalition 05/08/2003

OWL-S:Bringing Services tothe Semantic Web

David Martin

SRI [email protected]

http://www.daml.org/services/

David Martin for DAML-S Coalition 05/08/2003

These slides will be available here:

www.daml.org/services/materials/swmu

and will be linked from the SWMU Agenda page

David Martin for DAML-S Coalition 05/08/2003

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)

David Martin for DAML-S Coalition 05/08/2003

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

David Martin for DAML-S Coalition 05/08/2003

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

David Martin for DAML-S Coalition 05/08/2003

URI, HTML, HTTPStaticWWW

500 million usersmore than 3 billion pages

Why Semantic Web Services?T

hanks to Dieter F

ensel (U. of Innsbruck)

for use of this material

David Martin for DAML-S Coalition 05/08/2003

URI, HTML, HTTPStaticWWW

Serious Problems in information•finding

•extracting•representing•interpreting

•and maintaining

RDF, RDF(S), OWLSemantic Web

Why Semantic Web Services?T

hanks to Dieter F

ensel (U. of Innsbruck)

for use of this material

David Martin for DAML-S Coalition 05/08/2003

Static

Dynamic

Bringing the computer back as a device for computation

URI, HTML, HTTP RDF, RDF(S), OWL

WWW Semantic Web

UDDI, WSDL, SOAP

Web Services

Why Semantic Web Services?T

hanks to Dieter F

ensel (U. of Innsbruck)

for use of this material

David Martin for DAML-S Coalition 05/08/2003

Bringing the web to its full potential

Static

Dynamic UDDI, WSDL, SOAP

Web Services

URI, HTML, HTTP RDF, RDF(S), OWL

WWW Semantic Web

Intelligent Web Services

Why Semantic Web Services?T

hanks to Dieter F

ensel (U. of Innsbruck)

for use of this material

David Martin for DAML-S Coalition 05/08/2003

“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

Commercial Web Services: Definition

David Martin for DAML-S Coalition 05/08/2003

• 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.

Commercial Web Services:Business Vision

David Martin for DAML-S Coalition 05/08/2003

Commercial Web Services:Emerging Standards

URI HTML HTTP

UDDI WSDL SOAP

David Martin for DAML-S Coalition 05/08/2003

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.

David Martin for DAML-S Coalition 05/08/2003

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?

David Martin for DAML-S Coalition 05/08/2003

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.

David Martin for DAML-S Coalition 05/08/2003

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”.

David Martin for DAML-S Coalition 05/08/2003

Sweet Spot: Matchmaking

From “Web Services Architecture W3C Working Draft”http://www.w3.org/TR/2002/WD-ws-arch-20021114/

Commercial Web Services:Basic Architecture

David Martin for DAML-S Coalition 05/08/2003

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.