The set of tools developed by Informatik IV comprises amongst others HIT, a modelling environment which supports the specification of modular and hierarchical descriptions of especially large and complex models. The analysis techniques provided by HIT include simulation and a large variety of exact and approximative, analytical and numerical techniques. These models are mapped onto a Markov chain for numerical analysis or simulative techniques are applied. HiQPN-Tool supporting the analysis of hierarchical QPN models, a superset of Coloured GSPNs and Queueing Networks. These models can be analysed with respect to qualitative and quantitative aspects.
All tools provide a graphical user interface and are available for usual type of workstations.
They are tested exhaustively and have been employed for the evaluation of operating systems in the development phase, future hardware architectures, and the assessment of distributed and telecommunication systems. The tools also suit for an evaluation of flexible manufacturing systems. Their practical usability has been proved by a large number of external installations in universities, research institutes and industry. On the combination of PE and other evaluation techniques Methods for a combined evaluation of functional and performance aspects are getting more and more important in the field of performability, and fault-tolerant and distributed systems. In performability models the rates between events concerning the normal system operations and the occurrence of error indicating events normally differ several orders of magnitude.