TY - GEN
T1 - Environment-friendly safety
AU - Kupferman, Orna
AU - Weiner, Sigal
PY - 2013
Y1 - 2013
N2 - Of special interest in verification are safety properties, which assert that the system always stays within some allowed region. For closed systems, the theoretical properties of safety properties as well as their practical advantages with respect to general properties are well understood. For open (a.k.a. reactive) systems, whose behavior depends on their on-going interaction with the environment, the common practice is to use the definition and algorithms of safety for closed systems, ignoring the distinction between input and output signals. In a recent work, Ehlers and Finkbeiner introduced reactive safety - a definition of safety for the setting of open systems. Essentially, reactive safety properties require the system to stay in a region of states that is both allowed and from which the environment cannot force it out. In this paper we continue their study and extend it to other families of properties. In the setting of closed systems, each safety property induces a set of finite bad prefixes - ones after which the property must be violated. The notion of bad prefixes enables a reduction of reasoning about safety properties to reasoning about properties of finite computations. We study reactive bad prefixes, their detection in theory and in practice, and their approximation by either a non-reactive safety property or by reasoning about the syntax of the formula. We study the dual notion, of reactive co-safety properties, and the corresponding theory of reactive good prefixes. For both safety and co-safety properties, we relate the definitions in the closed and open settings, and argue that our approach strictly extends the range of properties for which we can apply algorithms that are based on finite computations. Since the reactive setting is particularly challenging for general properties, such an application is significant in practice.
AB - Of special interest in verification are safety properties, which assert that the system always stays within some allowed region. For closed systems, the theoretical properties of safety properties as well as their practical advantages with respect to general properties are well understood. For open (a.k.a. reactive) systems, whose behavior depends on their on-going interaction with the environment, the common practice is to use the definition and algorithms of safety for closed systems, ignoring the distinction between input and output signals. In a recent work, Ehlers and Finkbeiner introduced reactive safety - a definition of safety for the setting of open systems. Essentially, reactive safety properties require the system to stay in a region of states that is both allowed and from which the environment cannot force it out. In this paper we continue their study and extend it to other families of properties. In the setting of closed systems, each safety property induces a set of finite bad prefixes - ones after which the property must be violated. The notion of bad prefixes enables a reduction of reasoning about safety properties to reasoning about properties of finite computations. We study reactive bad prefixes, their detection in theory and in practice, and their approximation by either a non-reactive safety property or by reasoning about the syntax of the formula. We study the dual notion, of reactive co-safety properties, and the corresponding theory of reactive good prefixes. For both safety and co-safety properties, we relate the definitions in the closed and open settings, and argue that our approach strictly extends the range of properties for which we can apply algorithms that are based on finite computations. Since the reactive setting is particularly challenging for general properties, such an application is significant in practice.
UR - http://www.scopus.com/inward/record.url?scp=84880752659&partnerID=8YFLogxK
U2 - https://doi.org/10.1007/978-3-642-39611-3_22
DO - https://doi.org/10.1007/978-3-642-39611-3_22
M3 - منشور من مؤتمر
SN - 9783642396106
T3 - Lecture Notes in Computer Science (including subseries Lecture Notes in Artificial Intelligence and Lecture Notes in Bioinformatics)
SP - 227
EP - 242
BT - Hardware and Software
PB - Springer Verlag
T2 - 8th International on Hardware and Software: Verification and Testing, HVC 2012
Y2 - 6 November 2012 through 8 November 2012
ER -