Abstract: A network system including M terminals each connected to the network, and a certain of the M terminals includes memory for storing information about the M terminals including the certain terminal in a manner that each of the M terminals is associated with one of N groups (N<M). Upon receiving first information from a different terminal, the certain terminal selects a group to which second information is to be transmitted, out of the N groups on the basis of the group associated with the different terminal, selects a terminal, to which the second information is to be transmitted, out of the terminals associated with the selected group and transmits the second information to the selected terminal.