Targeting safety-related errors during software requirements analysis

ABSTRACT

This paper provides a Safety Checklist for use during the analysis of software requirements for spacecraft and others safety-critical, embedded systems. The checklist specifically targets the two most common causes of safety-related software errors: (1) inadequate interface requirements and (2) discrepancies between the documented requirements and the requirements actually needed for correct functioning of the system. The analysis criteria represented in the checklist are evaluated by application to two spacecraft projects. Use of the checklist to enhance the software-requirements analysis is shown to reduce the number of safety-related software errors.

REFERENCES

• 1: ANSI/IEEE Standard Glossary of Software Engineering Terminology. New York: IEEE, 1983.
• 2: Proceedings of the Berkeley Workshop on Temporal and Real-Ttme Specijcatton. Eds. P. B. Ladkin and F. H. Vogt. Berkeley, CA: International Computer Science Institute, 1990, TR-90- 060.
• 3: J. Cullyer, "Safety-critical Control Systems ," Computing and Control Engineering Journal, Vol. 2, No. 5, Sept 1991, pp. 202-210.
• 4: Alan M. Davis, Software requirements: analysis and specification, Prentice Hall Press, Upper Saddle River, NJ, 1990
• 5: E. P. Doolan, Experience with Fagan's inspection method, Software—Practice & Experience, v.22 n.2, p.173-182, Feb. 1992 [doi>10.1002/spe.4380220205]
• 6: S/W Development Formai Inspections Course. Version H, Sept, 1992, D-8925, Software Product Assurance, Sect. 522, Jet Propulsion Laboratory.
• 7: M. K. Franklin and A. Gabrelian, "A Transformational Method for Verifying Safety Properties in Real-Time Systems," in Proceedings of the ReaLTime Systems Symposium, 1989, pp. 112 -123.
• 8: Carlo Ghezzi , Dino Mandrioli , Sandro Morasca , Mauro Pezzè, A Unified High-Level Petri Net Formalism for Time-Critical Systems, IEEE Transactions on Software Engineering, v.17 n.2, p.160-172, February 1991 [doi>10.1109/32.67597]
• 9: E. M. Gray and R. H. Thayer, "Requirements," in Aerospace Software Engineering, A Collection of Concepts, Ed. C. Anderson and M. Dorfman. Washington: AIAA, 1991, pp. 89-121.
• 10: Tom Henzinger , Zohar Manna , Amir Pnueli, Temporal proof methodologies for real-time systems, Proceedings of the 18th ACM SIGPLAN-SIGACT symposium on Principles of programming languages, p.353-366, January 21-23, 1991, Orlando, Florida, United States [doi>10.1145/99583.99629]
• 11: Matthew S. Jaffe , Nancy G. Leveson , Mats P. E. Heimdahl , Bonnie E. Melhart, Software Requirements Analysis for Real-Time Process-Control Systems, IEEE Transactions on Software Engineering, v.17 n.3, p.241-258, March 1991 [doi>10.1109/32.75414]
• 12: F Jahanian , A K Mok, Safety analysis of timing properties in real-time systems, IEEE Transactions on Software Engineering, v.12 n.9, p.890-904, Sept. 1986
• 13: John C. Kelly , Joseph S. Sherif , Jonathan Hops, An analysis of defect densities found during software inspections, Journal of Systems and Software, v.17 n.2, p.111-117, Feb. 1992 [doi>10.1016/0164-1212(92)90089-3]
• 14: Nancy G. Leveson, Software safety in embedded computer systems, Communications of the ACM, v.34 n.2, p.34-46, Feb. 1991 [doi>10.1145/102792.102799]
• 15: R. Lutz, "Analyzing Software Requirements Errors in Safety-Critical, Embedded Systems," Proceedings of the IEEE International Symposium on Requirements Engineering, Jan 1993, pp. 126-133.
• 16: Robyn R. Lutz , Johnny S. K. Wong, Detecting Unsafe Error Recovery Schedules, IEEE Transactions on Software Engineering, v.18 n.8, p.749-760, August 1992 [doi>10.1109/32.153384]
• 17: N. Lynch and H. Attiya, "Using Mappings to Prove Timing Properties," MIT/L CS/TM- ll?. b, Dec 1989.
• 18: P. G. Neumann, "The Computer-Related Risk of the Year: Weak Links and Correlated Events," in Proceedings of the Sixth Annual Conference on Computer Assurance. NIST/IEEE, 1991, pp. 5-8.
• 19: R. Razouk , M. Gorlick, Real-time interval logic for reasoning about executions of real-time programs, Proceedings of the ACM SIGSOFT '89 third symposium on Software testing, analysis, and verification, p.10-19, December 13-15, 1989, Key West, Florida, United States
• 20: John Rushby , Friedrich von Henke, Formal verification of algorithms for critical systems, Proceedings of the conference on Software for citical systems, p.1-15, December 04-06, 1991, New Orleans, Louisiana, United States
• 21: Jeannette M. Wing, A Specifier's Introduction to Formal Methods, Computer, v.23 n.9, p.8-23, September 1990 [doi>10.1109/2.58215]

INDEX TERMS

Primary Classification:
  D. Software
  D.2 SOFTWARE ENGINEERING

Additional Classification:
  D. Software
  D.2 SOFTWARE ENGINEERING
      D.2.2 Design Tools and Techniques
          Subjects: User interfaces

  K. Computing Milieux
  K.6 MANAGEMENT OF COMPUTING AND INFORMATION SYSTEMS
      K.6.3 Software Management
          Subjects: Software development

General Terms:
Design, Human Factors, Management, Measurement, Performance, Reliability, Theory