An approach to modelling and evaluating AGG based reliable software systems

AGG is a well established development environment which is used to model software systems in terms of graphs. Though AGG provides an appropriate basis for system modelling and verification, it can neither analyze nor evaluate the system reliability. In this paper, we propose an AGG-based strategy which, by combining generalized stochastic petri net (GSPN) and tools for reliability analysis, supports software system reliability modelling and evaluation. This work expands this idea in three directions: First, we give an AGG reliability model in which we add error attribute to AGG graph for capturing system error information, and at the same time performing the system error state transition through the AGG production. Second, we present how to map rules from the AGG reliability model into the GSPN one, which in turn can be used for reliability evaluation. The other direction is to use a Client/Server application to demonstrate our approach.