Can we verify complex systems reliably? This paper presents a model of a queue system comprising two non-deterministic finite-state machines, each augmented with reversal-bounded counters, connected by an unbounded queue. Unlike traditional models, the writer can make conditional moves that test the emptiness of the queue, enabling a conditional move. The researchers investigated the decidability of various verification problems, including reachability, safety, and blocking, while also exploring extensions such as pushdown stacks and two-way communication. They then consider some reachability questions concerning machines operating in parallel. This research is valuable for computer scientists and software engineers interested in formal verification, automata theory, and the design of concurrent systems. It offers insights into the limits of decidability for queue-connected machines and provides new approaches for modelling and verifying complex systems.
This paper, published in the International Journal of Foundations of Computer Science, is highly relevant to the journal's scope, which centers on the theoretical foundations of computer science. Its investigation into the decidability of verification problems in queue-connected multicounter machines aligns with the journal’s focus on automata theory, formal languages, and computational complexity.