
"Charme." In Lecture Notes in Computer Science, edited by D. Geist and E. Tronci. Vol. 2860. Springer, 2003. ISSN: 354020363X. DOI: 10.1007/b93958.



Antonio Bucciarelli, and Ivano Salvo. "Totality, Definability and Boolean Circuits." 1443 (1998): 808–819. Springer. DOI: 10.1007/BFb0055104.
Abstract: In the type frame originating from the flat domain of boolean values, we single out elements which are hereditarily total. We show that these elements can be defined, up to total equivalence, by sequential programs. The elements of an equivalence class of the totality equivalence relation (totality class) can be seen as different algorithms for computing a given settheoretic boolean function. We show that the bottom element of a totality class, which is sequential, corresponds to the most eager algorithm, and the top to the laziest one. Finally we suggest a link between size of totality classes and a well known measure of complexity of boolean functions, namely their sensitivity.



Giuseppe Della Penna, Benedetto Intrigila, Igor Melatti, Enrico Tronci, and Marisa Venturini Zilli. "Exploiting Transition Locality in Automatic Verification of Finite State Concurrent Systems." Sttt 6, no. 4 (2004): 320–341. DOI: 10.1007/s1000900401496.
Abstract: In this paper we show that statistical properties of the transition graph of a system to be verified can be exploited to improve memory or time performances of verification algorithms. We show experimentally that protocols exhibit transition locality. That is, with respect to levels of a breadthfirst state space exploration, state transitions tend to be between states belonging to close levels of the transition graph. We support our claim by measuring transition locality for the set of protocols included in the Mur$\varphi$ verifier distribution. We present a cachebased verification algorithm that exploits transition locality to decrease memory usage and a diskbased verification algorithm that exploits transition locality to decrease disk read accesses, thus reducing the time overhead due to disk usage. Both algorithms have been implemented within the Mur$\varphi$ verifier. Our experimental results show that our cachebased algorithm can typically save more than 40% of memory with an average time penalty of about 50% when using (Mur$\varphi$) bit compression and 100% when using bit compression and hash compaction, whereas our diskbased verification algorithm is typically more than ten times faster than a previously proposed diskbased verification algorithm and, even when using 10% of the memory needed to complete verification, it is only between 40 and 530% (300% on average) slower than (RAM) Mur$\varphi$ with enough memory to complete the verification task at hand. Using just 300 MB of memory our diskbased Mur$\varphi$ was able to complete verification of a protocol with about $10^9$ reachable states. This would require more than 5 GB of memory using standard Mur$\varphi$.



Enrico Tronci. "Introductory Paper." Sttt 8, no. 45 (2006): 355–358. DOI: 10.1007/s100090050212y.
Abstract: In todayÃ¢â‚¬â„¢s competitive market designing of digital systems (hardware as well as software) faces tremendous challenges. In fact, notwithstanding an ever decreasing project budget, time to market and product lifetime, designers are faced with an ever increasing system complexity and customer expected quality. The above situation calls for better and better formal verification techniques at all steps of the design flow. This special issue is devoted to publishing revised versions of contributions first presented at the 12th Advanced Research Working Conference on Correct Hardware Design and Verification Methods (CHARME) held 21Ã‚â€“24 October 2003 in LÃ¢â‚¬â„¢Aquila, Italy. Authors of well regarded papers from CHARMEÃ¢â‚¬â„¢03 were invited to submit to this special issue. All papers included here have been suitably extended and have undergone an independent round of reviewing.



Giuseppe Della Penna, Benedetto Intrigila, Igor Melatti, Enrico Tronci, and Marisa Venturini Zilli. "Finite horizon analysis of Markov Chains with the Mur$\varphi$ verifier." Int. J. Softw. Tools Technol. Transf. 8, no. 4 (2006): 397–409. SpringerVerlag. ISSN: 14332779. DOI: 10.1007/s1000900502167.
Abstract: In this paper we present an explicit diskbased verification algorithm for Probabilistic Systems defining discrete time/finite state Markov Chains. Given a Markov Chain and an integer k (horizon), our algorithm checks whether the probability of reaching an error state in at most k steps is below a given threshold. We present an implementation of our algorithm within a suitable extension of the Mur$\varphi$ verifier. We call the resulting probabilistic model checker FHPMur$\varphi$ (Finite Horizon Probabilistic Mur$\varphi$). We present experimental results comparing FHPMur$\varphi$ with (a finite horizon subset of) PRISM, a stateoftheart symbolic model checker for Markov Chains. Our experimental results show that FHPMur$\varphi$ can handle systems that are out of reach for PRISM, namely those involving arithmetic operations on the state variables (e.g. hybrid systems).



Igor Melatti, Robert Palmer, Geoffrey Sawaya, Yu Yang, Robert Mike Kirby, and Ganesh Gopalakrishnan. "Parallel and distributed model checking in Eddy." Int. J. Softw. Tools Technol. Transf. 11, no. 1 (2009): 13–25. SpringerVerlag. ISSN: 14332779. DOI: 10.1007/s100090080094x.
Abstract: Model checking of safety properties can be scaled up by pooling the CPU and memory resources of multiple computers. As compute clusters containing 100s of nodes, with each node realized using multicore (e.g., 2) CPUs will be widespread, a model checker based on the parallel (shared memory) and distributed (message passing) paradigms will more efficiently use the hardware resources. Such a model checker can be designed by having each node employ two shared memory threads that run on the (typically) two CPUs of a node, with one thread responsible for state generation, and the other for efficient communication, including (1) performing overlapped asynchronous message passing, and (2) aggregating the states to be sent into larger chunks in order to improve communication network utilization. We present the design details of such a novel model checking architecture called Eddy. We describe the design rationale, details of how the threads interact and yield control, exchange messages, as well as detect termination. We have realized an instance of this architecture for the Murphi modeling language. Called Eddy_Murphi, we report its performance over the number of nodes as well as communication parameters such as those controlling state aggregation. Nearly linear reduction of compute time with increasing number of nodes is observed. Our thread task partition is done in such a way that it is modular, easy to port across different modeling languages, and easy to tune across a variety of platforms.



Roberto Gorrieri, Ruggero Lanotte, Andrea MaggioloSchettini, Fabio Martinelli, Simone Tini, and Enrico Tronci. "Automated analysis of timed security: a case study on web privacy." International Journal of Information Security 2, no. 34 (2004): 168–186. DOI: 10.1007/s1020700400379.
Abstract: This paper presents a case study on an automated analysis of realtime security models. The case study on a web system (originally proposed by Felten and Schneider) is presented that shows a timing attack on the privacy of browser users. Three different approaches are followed: LHTimed Automata (analyzed using the model checker HyTech), finitestate automata (analyzed using the model checker NuSMV), and process algebras (analyzed using the model checker CWBNC). A comparative analysis of these three approaches is given.



Enrico Tronci. "Equational Programming in LambdaCalculus via SLSystems. Part 1." Theoretical Computer Science 160, no. 1&2 (1996): 145–184. DOI: 10.1016/03043975(95)001050.



Enrico Tronci. "Equational Programming in LambdaCalculus via SLSystems. Part 2." Theoretical Computer Science 160, no. 1&2 (1996): 185–216. DOI: 10.1016/03043975(95)001069.



Corrado BÃ¶hm, and Enrico Tronci. "About Systems of Equations, XSeparability, and LeftInvertibility in the lambdaCalculus." Inf. Comput. 90, no. 1 (1991): 1–32. DOI: 10.1016/08905401(91)900579.

