State-space modelling of software for distributed systems has been effective in exposing design faults and has provided a method for the placement of software fault-tolerant structures. The most widely known methods (in the United Kingdom) have used Petri-net modelling. However, Petri nets are not the only representations available to the designer. The paper considers the use of the UCLA Graphical Model of Behaviour (GMB) in the design and simulation of software for distributed systems with emphasis on the study of dynamic interprocess interactions. It is shown that GMB possesses a number of analytical features which improve the models. A case study of the design of robust software for a safety critical application shows that GMB provides a complementary, and in some respects superior, method to Petri-net modelling.
['Geoffrey F. Carpenter', 'Andrew M. Tyrrell']
The use of GMB in the design of robust software for distributed systems