[Back] [PDF

Open Issues and Challenges in Security-aware Real-Time Scheduling for Distributed Systems

Tao Xie1    Xiao Qin1    Man Lin2    

1 Department of Computer Science
   New Mexico Institute of Mining and Technology
   801 Leroy Place, Socorro, New Mexico 87801
2 Department of Computer Science

St. Francis Xavier University

Antigonish, NS, B2G 2W5, Canada

Task Scheduling for real-time distributed systems has been investigated extensively in the literature. However, conventional wisdom in dynamic scheduling ignores security requirements in real-time applications. As such, in addition to factoring quality of security in real-time applications running in the system, real-time scheduling algorithms need to be security-aware in nature. In this paper we first identify the open issues and challenges involved in designing and implementing security-aware real-time scheduling schemes, which are intended to consider both security and real-time constraints for distributed systems. Then five approaches towards achieving security aware in real-time scheduling are described: a security-aware architecture, a uniprocessor real-time scheduling algorithm with security awareness (EDF_OPTS) using a preliminary security overhead model and overall system performance metrics, security-aware real-time scheduling for homogeneous and heterogeneous distributed systems, and a feedback control mechanism to improve quality of security and schedulability in run time. Discussions on future security overhead models are also provided. Simulation results show that our EDF_OPTS algorithm significantly improves system performance in terms of quality of security and schedulability over three baseline algorithms under a wide range of workload characteristics.

Appeared in Journal of Information, Vol. 9, No. 2, 2006.