Using the Event Calculus for the Performance Monitoring of Service-Level Agreements for Utility Computing

The automated performance monitoring of contracts, in terms of tracking contract state, is an important issue investigated in this work. We define contract state to be the sum of the normative relations that hold between contract parties. In order to facilitate state tracking, we define an XML formalisation of the Event Calculus, ecXML. This language is used to describe how a contract’s state evolves, according to events that are described in the contract. The work is grounded in the domain of Utility Computing (UC). UC is concerned with the provisioning of computational resources (computepower, storage, network bandwidth), on a per-need basis, to corporate businesses. Service-level Agreements (SLAs) contracts between a provider and a customer are a sine qua non in the deployment of UC.