A network system broadcast data from one node to a plurality of other nodes, which can decrease the time required for broadcast. A transfer source node divides the transfer data to be broadcasted, and transfers each divided data separately from the network adapters of the transfer source node to the network adapters of the other nodes, and the other nodes transfer the received data to the network adapters of the other nodes other than the transfer source node. Since more nodes (network adapters) can participate in data transfer in the second data transfer, high-speed transfer processing can be implemented, and the transfer processing time for broadcast can be decreased.