Enabling execution of service workflows in grid/cloud hybrid systems

Cloud computing systems provide on demand access to computational resources for dedicated use. Grid computing allows users to share heterogeneous resources from multiple administrative domains applied to common tasks. In this paper we discuss the characteristics and requirements of a hybrid system composed of both grid and cloud technologies. We propose an infrastructure which is able to manage the execution of service workflows in such system. We show how the infrastructure can be expanded by acquiring computational resources on demand from the cloud during the workflow execution, and how it manages these resources and the workflow execution without user interference.