A networking system consists of multiple computing devices connected to multiple networking processing engines each containing a memory system including a random access device. A placeholder for a parameter of an interface to an endpoint such as a data processing system or virtual machine may be provided in a network access control rule, instead of a static parameter. By providing the metal oxide film, generation of a parasitic channel on the back channel side of the oxide semiconductor film in the transistor can be prevented. One of the plurality of multiplexers may be configured to selectively supply one of the copies of the data unit from one of the memories.