1 Discovery and Mediation using Diane Service Descriptions Ulrich Küster University Jena Germany

2 What is DSD?  Goal of DIANE Service Descriptions: Complete efficient automation of discovery and invocation:  Discovery of suitable services (Focus on efficient matching of request – offer)  Correct invocation (filling of parameters) Semantic description of services: „DSD- DIANE Service Descriptions“

3 Basic Ideas  Concentrate on the basic, but don't block extensions  Basic Services:  two-phase choreography (n estimation steps, 1 execution step)  DSD language:  Intuitive, simple language  Extended by special constructs  Keep automated processing in mind  Provide efficient matcher

4 Main characteristics of DSD (1)  Own layered ontology language  special elements for service descriptions  Operational elements  to capture world altering effects  expressed as states (instance of state ontology)  purely state oriented  Aggregational elements  to capture sets of effects  Moon sells more than one item  offers as configurable sets of effects

5 Main characteristics of DSD (2)  Selecting elements  to support configuration by the requestor  via input/output variables  Valuing elements  to express preferences of the requestor  via fuzzy sets, strategies, …  unbiased matching  How does it look like?  How to solve discovery challenge?

6 Excerpt from Donau supplier service offer service instance

7 Example request service instance

8 How to solve the mediation problem?

9 Summary & Conclusion  Very well suited for discovery scenario  modelling of the given services straightforward  all aspects can be covered  Not as strong w.r.t. mediation scenario  no support for complex choreographies  need for BPEL wrapper  "overkill"?

10 Thank you for your attendance! Questions? Ulrich Küster DIANE project (services in ad hoc networks)