As events arrive, they are stored in the repository, which is analyzed for goal satisfaction. The results may be presented on a dash board or they may guide active responses, such as selecting alternative services. The service monitoring repository stores event data as well as analysis results. It consists of five layers.
• Level 0(events): The lowest layer stores raw data such as, “agent x receives message m from agent y”.
• Level 1(ontology): The next layer stores an interpretation of the event data using terms form a selected ontology.
• Level 2(Transaction Properties): Properties of level 1 events are stored at layer
2, for example, the property “agent x never violates a commitment” is true.
• Level 3(Metaproperties): Properties about properties are stored at layer 3, for example, “property p1 has a 75 percent success to failure ratio over the last 72 hours”.