摘要 |
Individual communication terminals are connected to a communication network in which one communication terminal functions as a parent that has a relay function, the other communication terminals function as children, and transmitting and receiving of communication messages between child communication terminals are performed via the parent. Each communication terminal transmits a holding list that lists information about data that the own communication terminal holds, to other communication terminals. Further, each communication terminal temporarily stores holding lists received from other communication terminals. Each communication terminal, while it does not function as a parent, preferentially selects the holding list that does not match that of the own communication terminal and whose transmission source is the parent communication terminal, among the stored holding lists, and, while the own communication terminal functions as a parent, selects any holding list that does not match that of the own communication terminal. Each communication terminal transmits and receives communication messages with another communication terminal that is a transmission source of the selected holding list so that data sharing is performed. |