International Symposium on Services Science, Leipzig, March 23-25, 2009. A Service Description Language for the Internet of Services Jorge Cardoso, Matthias Winkler, Konrad Voigt SAP Research Chemnitzer Strasse 48 01187 Dresden, Germany {jorge.cardoso|matthias.winkler|konrad.voigt}@sap.com Abstract: Services currently govern economies and will unquestionably become even more significant in the near future. This trend is supported by the launch of a proposal for a Directive on Services in the Internal Market 1 1 Introduction from the European Commission. Informa- tion and communication technology are presently being explored to provide infrastructures to support the notion of the Internet of Services which will enable providers to sell and consumers to purchase services. Such infrastructures will require research and develop- ment of new theories, concepts, models and technologies. As such, in this paper, we pre- sent a Universal Service Description Language (USDL), an approach to model service descriptions to enable the publication, discovery, selection, contracting and monitoring of service. Services currently govern economies and will unquestionably become even more significant in the near future. Outsourcing is one of the main reasons behind the growing number of service available since it allows companies to concentrate on their core competencies, reduce costs and take advantage of highly specialized external expertise. IBM, for example, which is a main producer of goods, has generated in 1998 more than half its revenues from services [IBM98]. The European directive for services 1 promises to increase the trade of services in the future. In business, a service is the non-material equivalent of a good. It is considered to be an activity which is intangible by nature which is provided by a service provider to a service consumer to create a value possibly for both parties. Services normally provide a human value in the form of work, information, advice, skills and expertise. In traditional economies, services are typically discovered and invoked manually, but their realization maybe performed by automated or ma- nual means (or a combination of both). Services can also be defined as a diverse group of eco- nomic activities not directly associated with the manufacture of goods, mining or agriculture [OEC00]. Examples of services include hair cutting, house painting or letter typing. Services can be categorized according to their economic area. For example, engineering servic- es, healthcare services, telecommunications services, distribution services and retailing services. We use the term universal services to refer to any type of services independently of their eco- nomic area. The term Internet of Services (IoS) [ST07] refers to the infrastructure that enables 1 http://ec.europa.eu/internal_market/services/services-dir/proposal_en.htm