The SGW 80 is disposed between the eNB 70 and the PGW 90, and relays user data. User data may be referred to as user (U)—plane data. The PGW 90 is a gateway to an external network differing from the EPC, and performs communication with the AS 130 disposed on the external network. The external network may be, for example, a network managed by a carrier such as an application provider, or a packet data network (PDN). The PGW 90 is disposed between the AS 130 and the SGW 80, and relays user data. The SGW 80 and the PGW 90 may execute traffic control on user data transmitted from the UE 60.