Formal verification

Formal verification that this result actually satisfies Equation (14.13) is an exercise in partial differentiation, but a physical interpretation will confirm its validity. Consider a small group of molecules that are in the reactor at position z at time t. They entered the reactor at time i = t — (zju) and had initial composition a t, z) = ai (t ) = ai (t — z/u). Their composition has subsequently evolved according to batch reaction kinetics as indicated by the right-hand side of Equation (14.14). Molecules leaving the reactor at time t entered it at time t — t. Thus,... 

In formal verification, we verify that a system is correct with respect to a specification. When verification succeeds and the system is proven to be correct, there is still a question of how complete the specification is, and whether it really covers all the behaviours of the system. 

Mead95 Catherine A. Meadows Formal Verification of Cryptographic Protocols A Survey Asiacrypt 94, LNCS 917, Springer-Verlag, Berlin 1995, 133-150. 

In Australia a formal verification protocol was developed with independent auditors. A company site is selected by the PACIA and the site is asked to nominate one of the auditors. Since 1995 some 104 self-assessments have been verified. A similar third-party certification process is currently being developed in the UK, and this became a mandatory requirement for CIA members at the end of 2000. 

Following connection of the analytical equipment to the core LIMS, formal verification of data values within the core LIMS database, screen displays and reports may be performed. The vehicle for this testing will be the second stage OQ Protocol. 

Formal verification - A series of techniques used to create mathematical proof that a piece of code will deliver predictable outcomes. 

Abstract. This paper introduces an agent-hased approach to analyze the dynamics of accidents and incidents in aviation. The approach makes use of a number of elements, including formahzation of a real world scenario, agent-based simulation of variations of the scenario, and formal verification of dynamic properties against the (empirical and simulated) scenarios. The scenario formalization part enables incident reconstruction and formal analysis of it. The simulation part enables the analyst to explore various hypothetical scenarios under different circumstances, with an emphasis on error related to human factors. The formal verification part enables the analyst to identify scenarios involving potential hazards, and to relate those hazards (via so-called interlevel relations) to inadequate behavior on the level of individual agents. The approach is illustrated by means of a case study on a runway incursion incident, and a number of advantages with respect to the current state-of-the-art are discussed. 

Formal Verification Proofs of properties of the specification and proofs of properties of the refined implementation against the specification. 

SM96] M. Srivas and S. Miller. Applying formal verification to the aamp5 microprocessor A case study in the industrial use of formal methods. J. on Formal Methods in System Design 8 153-188, 1996. 

In order to establish firm grounds for the definition of RTL synthesis subsets, and allow the formal verification of model equivalence, where one description is written in VHDL and the other in Verilog, the most obvious approach is to define the semantics of both languages in the same formal mathematical model. The advantage is twofold first it is possible to reduce the complexity of the task by reducing the many syntactic variations of the same behavior to a single normal form, and reason on that normal form second, one can benefit from the existence of formal verification software, by providing a relatively simple translator from a kernel format for the semantic model to the input format of a formal verification tool that can reason on the semantic model. 

The rest of this paper is organized as follows. Section 2 presents our approach to Verilog-VHDL interoperability around a Hierarchical Finite State Machine semantic model. Section 3 defines a common interpretation in that model for a RTL subset of Verilog and VHDL, the emphasis being on the illustration of the approach taken rather than on a complete formal derivation, which would exceed the space of this paper. Section 4 presents an implementation of a translator from SMP to Blif-mv, the intermediate formats for the semantic model in the Prevail and VIS systems, enabling formal verification of VHDL-Verilog equivalence in the VIS environment... 

UNKING VHDL AND VERILOG FOR FORMAL VERIFICATION AND SYNTHESIS... 

Hakim Bouamama was a research engineer at Laboratoire TIMA until June 97 where he worked on formal verification from VHDL, and was involved in the Prevail project. He now is associated with Silvaco, Santa Clara (Ca), U.S.A. He received the Engineer degree from ENSIMAG, Grenoble, France. 

However, we expect to use a more deterministic semantics for formal verification, since the proofe can be expected to be dramatically smaller. 

We are currently pursuing further research in exploring the theoretical properties of the logic, justifying the semantics, and refining and integrating our formalization approach into a formal verification system. 

Salem, A. and Borrione, D. (June 1990) Automatic Formal Verification of VHDL Descriptions A First Prototype. ARTEMIS Tedmical Report RR-823-I, Grenoble. 

HDDs and symbolic techniques have undergone major improvements in the last decade in different fields of CAD and symbolic FSM state space exploration techniques represent one of the major recent results of formal verification. 

CheckOfF-M is a formal verification tool which performs model checking. Model checking allows you to find errors in a design and to verify critical properties, such as the absence of deadlocks and whether the design performs specified functions. You provide a set of logical properties which the design should possess, and CheckOff-M tells you if the design omits required behavior or includes unwanted behavior. For example, you can check that (i) mutually exclusive events cannot occur concurrently, or (ii) a desired event will occur at a specific time. 

Coudert, O. k Madre, J. C. (1990), A unified firamework for the formal verification of sequential circuits, in International Conference on Computer-Aided Design . 

Zhou, Z., Song, X., Tahar, S., Corella, F., Cemy, E. Langevin, M. (1996), Formal verification of the island tunnel controller using multiway decision graphs, in Proc. of International Conference on Formal Methods in Computer Aided Design (FMCAD 96) , Palo Alto, CA, USA, pp. 233-247. 

Moreover, Nepal is able to deal with real network topologies and with the real implementation of protocols, instead of a mathematical model. Thus, it can discover problems related to all the features of protocols, including those features that are impossible to handle with formal verification techniques. 

Claesen, L., Proesmans, F., Verlind, E. DeMan, H. (1990), SFG-tracing a formal verif. methodology, in Proc. ACM-SIGDA Worksh. , Miami. 

Software systems are debugged by the user community over time. Every software product is followed by a potentially infinite sequence of patches. The same is true of hardware products, including processors, although sometimes compilers help us with die work arounds. It seems clear that hardware designers will be using formal verification both within and between levels, and test vectors, for die foreseeable future. 

So industry lowers high-level design specifications by hand, and formal verification s chief role is to make sure that it has been done right. 

Fault tolerance is a challenge in all complex systems. The simulation of the behaviour of the system in the event of faults helps in the definition of the fault tolerance techniques to be applied. We presented a fault injection tool at model level that currently is used as a tool to complement formal verification methods. This... 

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