Tutorial 1: Semantic Service Descriptions - Relevance for Mobile Applications, Requirements and State of the Art

Speakers

Michael Klein, University of Karlsruhe, Germany & Dr. Birgitta König-Ries, University of Jena, Germany

Abstract

Service oriented computing (SOC) is a promising programming paradigm to create robust, context-aware applications in mobile environments independent from the underlying network. This paradigm will enable mobile users to access resources on-the-fly even in unknown environments and even using small devices with limited capabilities.

A main task here is to automate the complete process from service search over matching, selecting and invocation. The most important technique to achieve this is an appropriate description of the services. Therefore, in this tutorial, an overview over existing syntactic (like WSDL) and semantic (like OWL-S, WSMO, and DSD) service descriptions is given.

Outline

1. Why should I care about semantic service descriptions? (30 min)
   In this first part of the tutorial, we will motivate, why service orientation is a (if not the) suitable paradigm for mobile computing. We will explain how mobile users with small devices that move in unknown environments will be able to access a wealth of information and functionality, if a service-oriented approach is used. We will further motivate why this requires semantic service descriptions.
2. What should a semantic service description look like? (30 min)
   The second part of the tutorial deals with requirements towards semantic service descriptions. It explains what is needed in such a description to fully exploit the potentials of service- orientation. A central concept that will be introduced in this section is “matching”, the (automatic) comparison of service offers and requests to find an offer that is able to fulfil a given request.
3. What is out there? (Part 1: Basics, WSDL) (45 min)
   The third part of the tutorial covers the basics of service-orientation. It introduces the service triangle as well as WSDL, SOAP und UDDI as today’s standards for service oriented applications. It also explains why these are not enough to achieve the goal of resource sharing in dynamic environments.
4. What is out there? (Part 2: OWL-S) (45 min)
   OWL-S is the oldest and probably most widely used semantic service description language. This part of the tutorial introduces the main concepts of OWL-S, explains how matching is done in this technology and gives an overview of the tool support provided for this language. Also, we will analyze the current status of this language and discuss whether it is suitable to support our requirements.
5. What is out there? (Part 3: WSMO) (45 min)
   WSMO is a rather young but promising competitor of OWL-S. Analogous to the OWL-S part, we will look at the key concepts, the matching, the tool support and the status of WSMO. We will discuss whether WSMO is suitable to fulfil all the requirements we have identified earlier.
6. What is out there? (Part 4: DSD) (45 min)
   To wrap up the discussion of semantic service descriptions, we give a brief introduction to our own DIANE Service Description, a prototypical ontology language and service description language that enables the exploitation of the full potential of service orientation.
7. What was all this about? (30 min)
   Returning to the beginning of the tutorial, we will summarize how and if each of the techniques presented can enable resource sharing in dynamic environments and can thus support mobile users.

Intended audience

The tutorial is of interest to researchers and practitioners trying to achieve resource sharing in dynamic environments. The tutorial does not require any particular prior knowledge; however some background on distributed data management might be helpful.

Biographies

Michael Klein studied computer science at the University of Karlsruhe in Germany. Since 2001, he is working towards his PhD at the Institute for Program Structures and Data Organization at the University of Karlsruhe. His main research area is semantic descriptions for mobile services. Michael has published extensively on this and related topics, and has been involved in teaching mobile information systems technology.

Birgitta König-Ries recently became an Associate Professor with the Institute for Computer Science at the Friedrich-Schiller-University Jena, Germany. Before that, she has spent time as a postdoctoral research associate with the University of Louisiana at Lafayette and Florida International University and as an assistant professor at the University of Karlsruhe, Germany, She got her PhD from that school in 1999. Currently, her research is focused on resource sharing in dynamic, in particular mobile, environments. Birgitta is chair of the working group on mobile databases and information systems within the German Informatics Society (GI). She has (co-)organized several workshops and seminars on mobile information management (e.g. the EDBT 2004 Workshop "Pervasive Information Management" and the Dagstuhl seminar "Mobile Information Management" (October 2004)), has been a member of the program committees of a number of related workshops and conferences, and has been teaching advanced courses on mobile information management and resource sharing for several years.