presented are methods for performing a constant time flow lookup utilizing parallel processing technology . the methods are suitable for multiprocessor and / or multi - core processor computing environments . the method generates hash table driven tables of exact flow matching patterns and then provides the generated tables to parallel processing based flow selection procedure that iteratively finds the highest priority flow from the exact flow matching patterns . the method is scalable based on the linear relationship between the number of processors and / or processor cores and the time required to perform the lookup . the method is also portable because it does not require any special or custom hardware typically associated with this type of lookup .