Secure multi-level parallel execution of scientific workflows on HPC grid resources by combining taverna and UNICORE services

Scientific workflows have emerged as a flexible and easily comprehensible way to implement complex multi-step data analysis problems. With surging data volumes and rising complexity of these workflows the demand for parallel, distributed execution of such workflows in high performance computing (HPC) and high throughput computing (HTC) environments has increased significantly. One of the major challenges when migrating client based tools to large distributed environments is security. Some workflow management systems (WMS) like Taverna, a system widely used in the life science community, provide basic security features. Hence, during the execution of a Taverna workflow on the client individual workflow steps can be securely distributed via UNICORE on the Grid. But WMS generally lack extended security mechanisms, such as trust delegation to support an extended distributed Grid submission mechanism of entire workflows. We describe a novel security propagation mechanism in this paper to enable a secure workflow submission. Additionally, we describe our optimization use case and its performance in an established three tier Grid architecture.