A video data sending device comprises a receiving part for receiving sending requests from terminals, a sending request selection part for determining whether the sending request for video data or not, a video data management part for executing sending control of the video data in case of the sending request for the video data, a video data sending part for returning the video data to the terminal corresponding to the sending request for the video data, a data management part for executing sending control of data other than video data in case of the sending request for the data and a data sending part for returning the data other than video data to the terminal.
A data high-rate returning device comprises a data storing part for storing returning data; a receiving part for receiving a packet having a sending request from each terminal; a header information storing part for storing sending-request-packet header information and returning packet header information; a returning packet preparation part which obtains the sending-request-packet header information from the packet, obtains the returning packet header information corresponding to the sending-request-packet header information from the header information storing part, obtains returning data from the data storing part based on the data part in the packet, and prepares a returning packet by the returning packet header information and the returning data; and a sending part for sending the returning packet to the terminal.