| 摘要 |
Provided is a band measurement device that takes the occurrence of retransmission timeout into account and estimates the bandwidth of a communication channel. A portable terminal acquires (S502, S503) a measured value for the round-trip time in a communication channel that is used for communication with a server and a measured value for the packet loss rate in the communication channel. The portable terminal then determines (S504, S505, S506) whether retransmission timeout is occurring in the server. When retransmission timeout is occurring in the server, the portable terminal calculates (S507) an estimated value for the bandwidth of the communication channel using a special throughput equation that includes the timeout time. When retransmission timeout is not occurring in the server, the portable terminal calculates an estimated value for the bandwidth of the communication channel using a normal throughput equation that does not include timeout time. |
