US Patent 7808910 Communication terminal, congestion control method, and congestion control program

The congestion in a network can be avoided by effectively utilizing a prepared network band even in a network where reception intervals of acknowledgments are not correct. According to the information about Ack or Sack (selective acknowledgment) received in a time of the minimum value of an RTT (rtt_min), the number of bytes of received segments (rcv_bytes) for which a receiving side acknowledges the reception is counted, and a received byte number setting unit 16 sets a congestion window (CWND) or a slow start threshold (SSTHRESH) when a packet loss occurs according to the number of bytes of received segments (rcv_bytes) counted by a received byte number counting unit 14 when a packet loss is detected by a loss detection unit 15.