A traffic control device that controls traffic of data transmitted from mobile units that belong to different groups, includes a memory, and a processor coupled to the memory, configured to switch an output destination for the data in accordance with a group and a type of the data, store the data to a plurality of data storage sections on a first-in-first-out basis, adjust an output timing for the stored data in accordance with the group and the type of the data, and attach an identifier to the data output from the plurality of data storage sections in accordance with the group and the type of the data.