DATA COMMUNICATION SYSTEM

摘要

A data communication system capable of eliminating the retransmission of useless data that is too late for the playback time at the receiving side, and, accordingly, capable of eliminating the wasteful utilization of transmission band. In the system, round-trip time RTT of a packet between the server (data transmitting apparatus) 100 and the terminal apparatus (data receiving apparatus) 200 is calculated, and only when the sum of the round-trip time RTT and present time is less than the playback time of the packet, retransmission request for lost packet which has high priority is made.