What is ESSaRel?
The devices that surround us in all areas of life are becoming more and more comfortable and powerful
due to intelligent embedded subsystems, replacing classical electromechanical solutions. As a result,
the number of embedded systems (ES) that are safety critical has increased significantly and will
continue to do so. Numerous examples can be found in the areas of automotive, medical and avionic
products such as fly-by-wire aircraft controls or the electronic stability program (ESP) used in modern cars.
During the development of safety-critical ES, automation and tight integration of dependability
analyses into the system design process save significant amounts of time and effort. Therefore, the
benefit of comprehensive development tools offering automated analyses based on (unified functional
and non-functional) system models can hardly be overestimated. Detailed models may be very large,
making it necessary to employ modularisation and abstraction mechanisms as well as efficient algorithms
A multitude of techniques have been proposed and used to model, analyse and predict software and
hardware quality characteristics. Among them are fault trees, Markov chains, Petri nets and statistical
reliability models. It may not be possible to obtain realistic results for ES by using a single technique
only. The application of different methods to different parts of a system, combining them into meaningful
results, can be a solution. This requires compositional approaches that integrate a variety of modelling
and analysis methods.
In order to achieve these goals the ESSaRel project has developed a flexible dependability integration
framework for ES. The ESSaRel framework can compose and integrate analysis models with different characteristics,
1. Component fault trees (CFT).
2. State/event fault trees (SEFT).
3. Markov chains.
to support developers of safety-critical ES. Similar to the predecessor tool UWG3
,the ESSaRel component concept makes it easy to model system components independently and to unite them for analysis.
The current version already offers CFT and Markov chains that can be
composed hierarchically. New model and analysis types will be easily addable by the way of plugins.
Try out ESSaRel today: