Deadlock detection by fair reachability analysis: multi-cyclic protocols and beyond

Fair reachability analysis is generalized to multi-cyclic protocols defined in the communicating finite state machine model as networks of n ≥ 2 processes with a multiple unidirectional ring topology and with arbitrary process structures. As a result, the deadlock detection problem is shown to be decidable for multi-cyclic protocols whose fair reachable global state space is finite. A sufficient condition for this finiteness is also given. Finally, it is advocated that the technique of fair reachability analysis is inherently infeasible beyond multi-cyclic protocols.