An Empirical Comparison of Formalisms for Modelling and Analysis of Dynamic Reconfiguration of Dependable Systems
This work addresses the problem of selecting appropriate formal methods for dynamic reconfiguration in dependable systems, which is incremental as it compares existing formalisms rather than introducing new ones.
The paper empirically compares three formalisms (VDM, CPOGs, and basic CCSdp) for modeling and analyzing dynamic reconfiguration in dependable systems, using an office workflow case study to evaluate their suitability based on modeling ability, verification of requirements, and adherence to ideal formalism criteria.
This paper uses a case study to evaluate empirically three formalisms of different kinds for their suitability for the modelling and analysis of dynamic reconfiguration of dependable systems. The requirements on an ideal formalism for dynamic software reconfiguration are defined. The reconfiguration of an office workflow for order processing is described, and the requirements on the reconfiguration of the workflow are defined. The workflow is modelled using the Vienna Development Method ($\mathrm{VDM}$), conditional partial order graphs ($\mathrm{CPOGs}$), and the basic Calculus of Communicating Systems for dynamic process reconfiguration (basic $\mathrm{CCS^{dp}}$), and verification of the reconfiguration requirements is attempted using the models. The formalisms are evaluated according to their ability to model the reconfiguration of the workflow, to verify the requirements on the workflow's reconfiguration, and to meet the requirements on an ideal formalism.