Model-driven specification of adaptive cloud-based systems

In cloud-based systems, business process models compose loosely coupled services to fulfill a certain goal. In order to ensure a high quality of service (QoS) of these systems, irregularities and violations need to be detected and handled at runtime by adapting the system. As a consequence, engineering such systems requires an explicit modeling of adaptation rules, which define how the system is adapted under certain conditions. These rules are defined based on models that specify QoS agreements as well as service bindings and business processes that are adapted. In this paper, we present a modeling approach for adaptive, cloud-based systems which supports the explicit specification of adaptation rules. We are introducing a metamodel for specifying bindings between business processes and cloud services considering Service Level Agreements that define the required QoS. In order to express adaptations of business processes on different levels of granularity, we are using an extended metamodel including fragments that group multiple process elements.