NBA

In the context of computer science, NBA stands for Non-deterministic Büchi Automaton. It is a type of automaton used in formal verification and model checking, particularly for systems that operate over infinitely long inputs or paths, such as those found in reactive systems.

An NBA is defined by a set of states, transitions between those states, an initial state, and a set of accepting states. The automaton operates on an input sequence, and a path is accepted if there exists at least one sequence of transitions that visits an accepting state infinitely often. This property makes NBAs particularly useful for verifying systems against temporal logic specifications, where properties such as „eventually“ and „always“ need to be checked over infinite behaviors.

Non-determinism in this context means that for some inputs or states, the automaton can transition to multiple possible next states. This characteristic allows NBAs to express a wider range of properties compared to deterministic models, but it also complicates the analysis and verification processes, requiring techniques that account for the uncertainty in state transitions.