TY - GEN
T1 - Dependability assessment of an industrial programmable logic controller via parametric fault-tree and high level Petri net
AU - Gaeta, Rossano
AU - Bobbio, Andrea
AU - Franceschinis, Giuliana
AU - Portinale, Luigi
N1 - Publisher Copyright:
© 2001 IEEE.
PY - 2001
Y1 - 2001
N2 - The case-study presented in this paper is aimed at assessing the dependability of a Programmable Logic Controller (PLC)devoted to safety functions. This case study has been brought to our attention by a national environmental agency and has been partially abstracted and anonymized to protect proprietary information. The PLC consists of a triplicated channel with a (2 ; 3) majority voting logic and is modeled by means of a recently proposed extension of the classical Fault Tree (FT)formalism called Parametric Fault Tree (PFT). In the PFT replicated units are folded and Parameterized so that only one representative of the various similar replicas is explicitly included in the model. The quantitative analysis of the PFT assumes s-independence among components and is based on combinatorial formulas. In order to include dependencies both in the failure and repair process, the PFT is directly converted into a particular class of High Level Petri Nets, called SWN. The paper illustrates the PFT formalism and the automatic conversion algorithm from a PFT into a SWN. Moreover; it is shown how various kind of dependencies can be accommodated in the obtained SWN model.
AB - The case-study presented in this paper is aimed at assessing the dependability of a Programmable Logic Controller (PLC)devoted to safety functions. This case study has been brought to our attention by a national environmental agency and has been partially abstracted and anonymized to protect proprietary information. The PLC consists of a triplicated channel with a (2 ; 3) majority voting logic and is modeled by means of a recently proposed extension of the classical Fault Tree (FT)formalism called Parametric Fault Tree (PFT). In the PFT replicated units are folded and Parameterized so that only one representative of the various similar replicas is explicitly included in the model. The quantitative analysis of the PFT assumes s-independence among components and is based on combinatorial formulas. In order to include dependencies both in the failure and repair process, the PFT is directly converted into a particular class of High Level Petri Nets, called SWN. The paper illustrates the PFT formalism and the automatic conversion algorithm from a PFT into a SWN. Moreover; it is shown how various kind of dependencies can be accommodated in the obtained SWN model.
UR - http://www.scopus.com/inward/record.url?scp=0012344568&partnerID=8YFLogxK
U2 - 10.1109/PNPM.2001.953353
DO - 10.1109/PNPM.2001.953353
M3 - Conference contribution
AN - SCOPUS:0012344568
T3 - Proceedings - 9th International Workshop on Petri Nets and Performance Models, PNPM 2001
SP - 29
EP - 38
BT - Proceedings - 9th International Workshop on Petri Nets and Performance Models, PNPM 2001
PB - Institute of Electrical and Electronics Engineers Inc.
T2 - 9th International Workshop on Petri Nets and Performance Models, PNPM 2001
Y2 - 11 September 2001 through 14 September 2001
ER -