1. An information processing system comprising: a plurality of sensing nodes including cameras; and a responding device, wherein each of said plurality of sensing nodes recognizes a moving object in a predetermined space using a plurality of recognition methods and sends the recognition result to a master sensing node selected from said plurality of sensing nodes; wherein said master sensing node sends a command to instruct said responding device to take a predetermined action in accordance with said recognition result; and wherein said responding device takes an action in accordance with said received command.