Enhancing Fault Tolerance of Real-Time Systems through Time Redundancy

  • Sandra R. Thuel
  • Jay K. Strosnider
Part of the The Kluwer International Series in Engineering and Computer Science book series (SECS, volume 285)


Fault-tolerant, real-time systems require correct, time-constrained results in the presence of faults. Missed deadlines in many high dependability systems can result in significant property damage or loss of human life. Historically, designers relied almost exclusively upon massive hardware replication to achieve their dependability goals. Research suggests that not only is this approach inadequate for dealing with certain fault classes, but also that it is inappropriate for many applications with strict space, weight, and cost constraints. Alternatively, time redundancy can be used to complement replication as a means to improve fault coverage and reduce the required level of replication for fault-tolerant system design. Although previous work has advocated the use of time redundancy to provide protection against hardware and software faults, there exists no formal methodology for allocating and managing such time. This chapter provides an overview of recent work in developing a comprehensive analytical framework for allocating and managing time redundancy to preserve the timing correctness of priority-driven, real-time systems in the presence of faults.


Priority Level Periodic Task Recovery Operation Aperiodic Task Schedule Overhead 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.


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Copyright information

© Kluwer Academic Publishers 1994

Authors and Affiliations

  • Sandra R. Thuel
    • 1
  • Jay K. Strosnider
    • 2
  1. 1.AT&0026;T Bell LaboratoriesHolmdel
  2. 2.Department of Electrical and Computer EngineeringCarnegie Mellon UniversityPittsburgh

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