Coordinated Atomic Actions for Dependable Distributed Systems: the Current State in Concepts, Semantics and Verification Means

Coordinated Atomic Actions (CAAs) have been introduced about ten years ago as a conceptual framework for developing fault-tolerant concurrent systems. All the work done since then extended the CAA framework with the capabilities to model, verify, and implement concurrent distributed systems following pre-defined development methodologies. As a result, CAAs, compared to other approaches available, offer a rich set of means for engineering dependable systems. Nevertheless, it is sometimes difficult to have a global and analytical view of all the features available as this concept provides a number of features which need to be applied in combination. The main contribution of this paper is in presenting a complete state-of-the-art overview of the work done around CAAs from the three perspectives: the definitions of the fundamental concepts, their various semantics and the means supporting formal verification. This paper is useful for the potential CAAs users in helping them to avoid misinterpretation when employing all the available features. Finally, our paper should contribute in better understanding of the likely directions in which the CAA framework may evolve in the near future.