Sommario: | Performance and dependability evaluation of complex systems by means of dynamic stochastic models may be impaired by the combinatorial explosion of their state space. Among the possible methods to cope with this problem, symmetry-based ones can be applied to systems including several similar components.
However, symmetry-based methods are less effective in case of partially symmetric systems (i.e., systems with mostly symmetric behavior and occasional local asymmetric behavior). To cope with this limitation, two approaches called Extended Symbolic Reachability Graph and Dynamic Symbolic Reachability Graph have been proposed in literature. In this paper we will discuss the effectiveness and applicative interest of these two methods by means of four model patterns. |