Provided is a data supply apparatus including a transmission device that sends data to another data supply apparatus; a reception device that receives data from another data supply apparatus; a data storing device that stores data in a storage device; and a data storage determination device that determines whether or not the received data should be stored in the storage device, based on a predetermined supply probability. In a typical example, the reception device receives the data to which supply probability information which indicates the supply probability has been appended; and the data storage determination device determines whether or not the received data should be stored in the storage device, based on the supply probability indicated by the supply probability information.