Semantics-Based Activity Synthesis: Improving On-Demand Provisioning and Planning

In the previous chapter, the possible role of semantics in Grid resource matching and brokerage is discussed. This chapter introduces semantics-based synthesis of activities for automatic workflow generation and improving on-demand resource provisioning. On-demand synthesis of Grid activities plays a significant role in automatic workflow composition and in improving service quality of a Grid resource provisioner. However, in the Grid, synthesis of activities has not been considered due to limited expressiveness of the representation of activity capabilities and the lack of adapted resource management means to take advantage of such activity synthesis. This chapter introduces a new mechanism for automatic synthesis of available activities for the Grid by applying ontology rules. Rule-based synthesis combines multiple primitive activities to form new compound activities. The synthesis process generates new compound activities that can be provisioned as new or alternative options for negotiation and advance reservation. This is a major advantage compared to other approaches that only focus on resource matching. The newly generated compound activities provide aggregated capabilities that otherwise may not be possible; this leads towards an automatic generation of complex workflow applications. Furthermore, we introduce semantics in capacity planning for improving optimization in resource allocation. We demonstrate advantages of semantic-based automatic synthesis of Grid activities.