Non-deterministic finite automata tree structure application apparatus and method

A method includes processing event data to detect a status of a network function. The event data is processed based on two or more conditions defined by a correlation policy. The correlation policy includes a non-deterministic finite automata tree (NFAT) structure correlation policy having a policy type. The method also includes determining a first value of a first condition of the two or more conditions. The method further includes determining a second value of a second condition of the two or more conditions. The method additionally includes determining the policy type of the NFAT structure correlation policy. The method also includes determining whether the first value is greater than a first preset value indicative of whether the first condition is satisfied. The method further includes determining whether the second value is greater than a second preset value indicative of whether the second condition is satisfied.