Abstract
Contemporary safety standards prescribe processes in which system safety requirements, captured early and expressed in the form of Safety Integrity Levels (SILs), are iteratively allocated to architectural elements. Different SILs reflect different requirements stringencies and consequently different development costs. Therefore, the allocation of safety requirements is not a simple problem of applying an allocation "algebra" as treated by most standards; it is a complex optimisation problem, one of finding a strategy that minimises cost whilst meeting safety requirements. One difficulty is the lack of a commonly agreed heuristic for how costs increase between SILs. In this paper, we define this important problem; then we take the example of an automotive system and using an automated approach show that different cost heuristics lead to different optimal SIL allocations. Without automation it would have been impossible to explore the vast space of allocations and to discuss the subtleties involved in this problem.
This is a preview of subscription content, log in via an institution to check access.
Access this chapter
Tax calculation will be finalised at checkout
Purchases are for personal use only
Preview
Unable to display preview. Download preview PDF.
References
Ward, D.D., Crozier, S.E.: The uses and abuses of ASIL decomposition in ISO 26262. In: 7th IET International Conference on System Safety, incorporating the Cyber Security Conference (2012)
Allen, M.: Cost Versus ASIL. ISO 26262 Functional Safety [LinkedIn] (February 2, 2012), http://www.linkedin.com/groups/Cost-versus-ASIL-2308567.S.92692199?view=&srchtype=discussedNews&gid=2308567&item=92692199&type=member&trk=eml-anet_dig-b_pd-ttl-cn&ut=1evtvoEm1QcBw1 (accessed May 1, 2014)
Papadopoulos, Y., Walker, M., Reiser, M.-O., Weber, M., Chen, D., Törngren, S.D., Abele, A., Stappert, F., Lönn, H., Berntsson, L., Johansson, R., Tagliabo, F., Torchiaro, S., Sandberg, A.: Automatic Allocation of Safety Integrity Levels. In: Proceedings of the 1st Workshop on Critical Automotive applications: Robustness and Safety (CARS 2010), Valencia, Spain, April 27, pp. 7–10. ACM, New York (2010), doi:10.1145/1772643.1772646, ISBN: 978-1-60558-915-2
Azevedo, L.S., Parker, D., Walker, M., Papadopoulos, Y., Araujo, R.E.: Assisted Assignment of Automotive Safety Requirements. IEEE Software 31, 62–68 (2014)
Papadopoulos, Y., Walker, M., Parker, D., Rüde, E., Hamann, R., Uhlig, A., Grätz, U., Lien, R.: Engineering Failure Analysis & Design Optimisation with HiP-HOPS. Journal of Engineering Failure Analysis 18(2), 590–608 (2011) doi:10.1016/j.engfailanal.2010.09.025, ISSN: 1350 6307
Mader, R., Armengaud, E., Leitner, A., Steger, C.: Automatic and Optimal Allocation of Safety Integrity Levels. In: Proceedings of the Reliability and Maintainability Symposium (RAMS 2012), Reno, NV, USA, January 23-26, pp. 1–6 (2012), doi:10.1109/RAMS.2012.6175431, ISBN: 978-1-4577-1849-6
Bieber, P., Delmas, R., Seguin, C.: DALculus – theory and tool for development assurance level allocation. In: Flammini, F., Bologna, S., Vittorini, V. (eds.) SAFECOMP 2011. LNCS, vol. 6894, pp. 43–56. Springer, Heidelberg (2011)
Parker, D., Walker, M., Azevedo, L.S., Papadopoulos, Y., Araújo, R.E.: Automatic decomposition and allocation of safety integrity levels using a penalty-based genetic algorithm. In: Ali, M., Bosse, T., Hindriks, K.V., Hoogendoorn, M., Jonker, C.M., Treur, J. (eds.) IEA/AIE 2013. LNCS, vol. 7906, pp. 449–459. Springer, Heidelberg (2013)
Azevedo L.S., Parker D., Walker M., Papadopoulos Y., and Araujo R. E.: Automatic Decomposition of Safety Integrity Levels: Optimisation by Tabu Search. 2nd Workshop on Critical Automotive applications: Robustness & Safety (CARS), at the 32nd International Conference on Computer Safety, Reliability, and Security (SAFECOMP 2013), Toulouse, France (2013)
Hansen, P., Lih, K.-W.: Heuristic reliability optimization by tabu search. Annals of Operations Research (63), 321–336 (1996)
Azevedo, L.P.: Hybrid Braking System for Electrical Vehicles: Functional Safety, M.Sc. thesis, Dept. Elect. Eng., Porto Univ., Porto, Portugal (2012)
de Castro, R., Araújo, R.E., Freitas, D.: Hybrid ABS with Electric motor and friction Brakes. Presented at the IAVSD2011 - 22nd International Symposium on Dynamics of Vehicles on Roads and Tracks, Manchester, UK (2011)
Author information
Authors and Affiliations
Editor information
Editors and Affiliations
Rights and permissions
Copyright information
© 2014 Springer International Publishing Switzerland
About this paper
Cite this paper
Azevedo, L.S., Parker, D., Papadopoulos, Y., Walker, M., Sorokos, I., Araújo, R.E. (2014). Exploring the Impact of Different Cost Heuristics in the Allocation of Safety Integrity Levels. In: Ortmeier, F., Rauzy, A. (eds) Model-Based Safety and Assessment. IMBSA 2014. Lecture Notes in Computer Science, vol 8822. Springer, Cham. https://doi.org/10.1007/978-3-319-12214-4_6
Download citation
DOI: https://doi.org/10.1007/978-3-319-12214-4_6
Publisher Name: Springer, Cham
Print ISBN: 978-3-319-12213-7
Online ISBN: 978-3-319-12214-4
eBook Packages: Computer ScienceComputer Science (R0)