Patent ID: 7701935

Claim:
A network system in which a first and a second terminal carry out radio communications, wherein: if said first terminal determines that there is no communication path between said first terminal and said second terminal, said first terminal determines if there are one or more relay terminals which are capable of communicating with said second terminal and obtains and saves expectation values for the one or more relay terminals, said expectation values indicating a probability of transmitting data to said second terminal from the one or more relay terminals; said first terminal selects, on the basis of said expectation values saved by said first terminal, a relay terminal relaying data to be transmitted to said second terminal and transmits said data, together with a first information item indicating the address of said first terminal and a second information item indicating the address of said second terminal, to said relay terminal; if said relay terminal determines that there is no communication path between the said relay terminal and said second terminal, said relay terminal checks to determine if there are relay terminals capable of communicating with the second terminal, and obtains and saves expectation values of said relay terminals, said expectation values indicating a probability of transmitting data from said relay terminals to the second terminal; said relay terminal selects, based on said expectation values saved by said relay terminal, another relay terminal to transmit data to said second terminal and transmits data, together with a first information item indicating an address of said relay terminal and a second information item indicating an address of said second terminal to said another relay terminal until said another relay terminal transmits the received said first information item and said second information item, and said data, to said second terminal; and said second terminal, if it receives said first and second information items, and said data, transmits a completion report to said first terminal, on the basis of an expectation value saved in said second terminal.