System for transmitting stream data from server to client based on buffer and transmission capacities and delay time of the client

摘要

A terminal determines a target value of stream data to be stored in its buffer in relation to its buffer capacity and the transmission capacity of the network. Also, the terminal arbitrarily determines a delay time from when the terminal writes a head data of the stream data to the buffer to when the terminal reads the data to start playback in a range not exceeding a value obtained by dividing the buffer capacity by the transmission capacity. The target value and the delay time are then both notified to a server. Based on those notified values, the server controls the transmission speed so that the buffer occupancy of the terminal changes in the vicinity of the target value without exceeding the target value.