A comparative reliability analysis of ETCS train radio communications

StoCharts have been proposed as a UML statechart extension for performance and dependability evaluation, and were applied in the context of train radio reliability assessment to show the principal tractability of realistic cases with this approach. In this paper, we extend on this bare feasibility result in two important directions. First, we sketch the cornerstones of a mechanizable translation of StoCharts to MoDeST. The latter is a process algebra-based formalism supported by the Motor/Möbius tool tandem. Second, we exploit this translation for a detailed analysis of the train radio case study

From StoCharts to MoDeST: a comparative reliability analysis of train radio communications

StoCharts have been proposed as a UML statechart extension for performance and dependability evaluation, and have been applied in the context of train radio reliability assessment to show the principal tractability of realistic cases with this approach. In this paper, we extend on this bare feasibility result in two important directions. First, we sketch the cornerstones of a mechanizable translation of StoCharts to MoDeST. The latter is a process algebra-based formalism supported by the Motor/Möbius tool tandem. Second, we exploit this translation for a detailed analysis of the train radio case study

A comparison of Spin and the mu mu CRL toolset on HAVi leader election protocol

This paper describes an attempt to compare two toolsets allowing generation of finite labeled transition systems from underlying concurrent specification languages. The comparison is done on a specification of the leader election protocol from Home Audio/Video interoperability (HAVi) architecture. Some important semantical differences of PROMELA and $mu$CRL are identified, that lead to big differences in size of the state spaces generated for equivalent specifications

Linearization in parallel pCRL

AbstractWe describe a linearization algorithm for parallel pCRL processes similar to the one implemented in the linearizer of the μCRL Toolset. This algorithm finds its roots in formal language theory: the `grammar' defining a process is transformed into a variant of Greibach Normal Form. Next, any such form is further reduced to linear form, i.e., to an equation that resembles a right-linear, data-parametric grammar. We aim at proving the correctness of this linearization algorithm. To this end we define an equivalence relation on recursive specifications in μCRL that is model independent and does not involve an explicit notion of solution

Behavioural analysis of an I2C Linux driver

We present an analysis of the behaviour of an I2C Linuxdriver, by means of model checking with the mCRL2 toolset and static analysis with UNO.We have reverse engineered the source code to obtain the structure and interactions of the driver. Based on these results, we have semi-automatically created an mCRL2 model of the behaviour of the driver, on which we have checked mutual exclusion properties. This revealed non-trivial potential errors, like unprotected usage of shared memory variables due to inconsistent locking and disabling/enabling of interrupts. We also applied UNO on the instrumented source code and were able to find the same errors. These defects were confirmed by the developers

Synthesis and Stochastic Assessment of Cost-Optimal Schedules

We present a novel approach to synthesize good schedules for a class of scheduling problems that is slightly more general than the scheduling problem FJm,a|gpr,r_j,d_j|early/tardy. The idea is to prime the schedule synthesizer with stochastic information more meaningful than performance factors with the objective to minimize the expected cost caused by storage or delay. The priming information is obtained by stochastic simulation of the system environment. The generated schedules are assessed again by simulation. The approach is demonstrated by means of a non-trivial scheduling problem from lacquer production. The experimental results show that our approach achieves in all considered scenarios better results than the extended processing times approach

Equivalence of recursive specifications in process algebra

We define an equivalence relation on recursive specifications in process algebra that is model-independent and does not involve an explicit notion of solution. Then we extend this equivalence to the specification language $mu$CRL