SERVER DEVICE, FILE TRANSMITTING/RECEIVING SYSTEM, AND FILE TRANSMISSION METHOD

摘要

PROBLEM TO BE SOLVED: To transmit files at substantially the same time from a server device to a plurality of terminal devices.SOLUTION: A server device 20 includes a data transmission section 21 and a data conversion section 22. The data conversion section 22 converts a file to be executed in terminal devices 31, 32, 33 into a plurality of data-transmission packets. The data transmission section 21 transmits the packets in multicast. The data transmission section 21 includes a server communication section 211 and a synthesized data storage section 212. The synthesized data storage section 212 stores synthesized data formed by synthesizing the packets. On receipt of a retransmission request, the server communication section 211 reads the synthesized data including a packet specified by the retransmission request, and transmits it in multicast.SELECTED DRAWING: Figure 1