Disclosed are data transmission-reception system and data transmission
method, in which a communication system includes: a first communication
device for transmitting outgoing data including content identification
data, transmitting party identification data, receiving party
identification data, and date and time data; a second communication
device for receiving the outgoing data and for transmitting content data
identified by the content identification data to a receiving party
identified by the receiving party identification data at a date and time
corresponding to the date and time data; and a third communication device
for receiving and reproducing the content data transmitted from the
second communication device.