An example of risk assessment of software systems specifications

This paper presents an example of risk assessment in complex real-time software systems at the early stages of development. A heuristic risk assessment technique based on colored Petri net (CPN) models is used to classify software according to its relative importance in terms of such factors as severity and complexity. The methodology of this technique is presented in a companion paper (Ammar et al., 1997). This technique is applied on the Earth Operation Commanding Center; a large component of NASA's Earth Observing System (EOS) project. Two specifications of the system are considered: a sequential model and a pipeline model. Results of applying the above technique to both CPN-based models yield different complexity measures. The pipeline model shows clearly a higher risk factor than the sequential model. Whereas using traditional complexity measures, the risk factors were similar in both models.