Discovery and Mediation using the DIANE Service Description

In this short paper, we briefly introduce the DIANE Service Description (DSD) and show how it can be used to support the problems stated in the exemplary Moon scenario of the SWS-Challenge-2006. 1 What is DSD? The goal of service-oriented computing is the ability to dynamically discover and invoke services at run-time, thus forming networks of loosely-coupled participants. The most important prerequisite is an appropriate semantic service description language – and with DIANE Service Description (DSD) [1] we try to provide such a language together with an efficient matching algorithm. One main difference between DSD and other semantic service description languages is its own light-weight ontology language that is specialized for the characteristics of services and can be processed efficiently at the same time. The basis for this ontology language is standard object orientation which is extended by four additional elements: – Services perform world-altering operation (e.g., after invoking the Donau supplier service, you own some computer equipment and your credit card has been charged) which is captured by operational elements. Thus, in DSD, services are primarily described by their effects – all other aspects (as flow of information, choreography etc.) are seen as secondary, derived properties. An effect is comprehended as the achievement of a new state, which in DSD is an instance from a state ontology. – Services offer/request more than one effect (e.g., you can obtain more than one product from the Donau supplier service) which is captured by aggregational elements. Thus, the effect of a service is typically a set of states. In DSD, these are declaratively defined which leads to descriptions as acyclic directed graphs (see example in the next section). – Services allow to choose among the offered effects (e.g., with the Donau supplier service, you can select which item you want to buy, where to ship it, and which credit card to be charged) which is captured by selecting elements. In DSD, selecting elements are represented as variables that can be integrated into set definitions, thus leading to configurable sets. Therefore, a service offer in DSD is represented by its effects as configurable sets of states.