Patent ID: 8924806

Claim:
A user terminal for receiving a plurality of data pieces for a plurality of processes that are simultaneously operated, each of the data pieces having an indicator indicating whether the data piece is new data or retransmitted data, the data pieces being transmitted from a network apparatus that changes a value of the indicator on a process-by-process basis, the user terminal comprising: a data receiving unit for receiving the data pieces with their corresponding indicator and a transmittable data size for each of the data pieces; a response transmitting unit for transmitting, to the network apparatus, a response indicating an acknowledgement or a negative acknowledgement for a received data piece; and an indicator determination unit for determining whether the indicator of the received data piece is the same as the indicator of a previous data piece received immediately previously for the same process as the process of the received data piece, determining whether the transmittable data size of the received data piece is the same as the transmittable data size of the previous data piece, and discarding, when the indicators are the same and the transmittable data sizes are the same, the received data piece.