SABA: A security-aware and budget-aware workflow scheduling strategy in clouds

• In this paper we address the Workflow Scheduling in Clouds.
• We consider security and cost considerations.
• We propose a Security-Aware and Budget-Aware algorithm.
• We present rigorous theoretical analysis and verify on six different real datasets.
• We demonstrate a trade-off relationship between make span and the monetary cost.

High quality of security service is increasingly critical for Cloud workflow applications. However, existing scheduling strategies for Cloud systems disregard security requirements of workflow applications and only consider CPU time neglecting other resources like memory, storage capacities. These resource competition could noticeably affect the computation time and monetary cost of both submitted tasks and their required security services. To address this issue, in this paper, we introduce immoveable dataset concept which constrains the movement of certain datasets due to security and cost considerations and propose a new scheduling model in the context of Cloud systems. Based on the concept, we propose a Security-Aware and Budget-Aware workflow scheduling strategy (SABA), which holds an economical distribution of tasks among the available CSPs (Cloud Service Providers) in the market, to provide customers with shorter makespan as well as security services. We conducted extensive simulation studies using six different workflows from real world applications as well as synthetic ones. Results indicate that the scheduling performance is affected by immoveable datasets in Clouds and the proposed scheduling strategy is highly effective under a wide spectrum of workflow applications.