US Patent 7764613 Communication control method and system

A transmitter device 20, in transmitting a predetermined number of data blocks out of a plurality of data blocks to a receiver device 10 via a relay device 40, divides and writes into data blocks transmitted in succession, a request code for requesting relay device 40 to relay remaining data blocks. Relay device 40, in the case of accepting the request shown in the request code that is divided and written in the data blocks transmitted from transmitter device 20, notifies the acceptance of the request to transmitter device 20. Transmitter device 20, upon receiving the notification, then transmits the remaining data blocks in succession to relay device 40.