A base station apparatus includes a processor, a memory and a communication circuit. The processor is configured to set a waiting period in which a packet from a terminal device to which a connection has not been established is awaited. The memory is configured to store data that is processed by a terminal device to which a connection is established. The communication circuit is configured to, upon receiving a first packet from a communication terminal device in the waiting period, transmit to the communication terminal device a second packet containing the data and information used by the communication terminal device for establishing a connection.