  A register automaton is a finite automaton with finitely many registers
ranging from an infinite alphabet. Since the valuations of registers are
infinite, there are infinitely many configurations. We describe a technique to
classify infinite register automata configurations into finitely many exact
representative configurations. Using the finitary representation, we give an
algorithm solving the reachability problem for register automata. We moreover
define a computation tree logic for register automata and solve its model
checking problem.
