In computer science, „NBA“ stands for „Nondeterministic Büchi Automaton.“ It is a type of finite-state machine that is used in the field of formal verification, particularly in model checking. An NBA extends the concept of a nondeterministic finite automaton (NFA) by incorporating acceptance conditions that are based on infinite sequences.
In an NBA, a run (an infinite sequence of transitions) is considered accepted if it visits a designated set of states, called accepting states, infinitely often. This feature allows NBA to express properties of systems that operate over infinite runs, which is crucial for verifying systems that can run indefinitely, such as reactive systems or those involving concurrent processes.
The significance of NBA lies in their ability to model and verify properties of systems described by linear temporal logic (LTL). They provide a powerful tool for reasoning about the behaviors of systems in situations where decisions may not be fully predictable or where multiple paths of execution can occur based on nondeterministic choices.