| 摘要 |
PROBLEM TO BE SOLVED: To suppress load on a network.SOLUTION: In an arbitrary specific terminal 10 in a network 1 having a plurality of terminals connected thereto, a request control information receiving section 11 receives request control information from another terminal. A request control information relay section 12 relays the request control information received by the request control information receiving section 11 to a terminal different from the other terminal. A presence control information replying section 13 identifies a transmission source terminal 20 as a terminal that has firstly transmitted the request control information from the request control information received by the request control information receiving section 11, sets the identified transmission source terminal 20 as the final destination of the presence control information indicating that the specific terminal 10 is present, and transmits the presence control information including the set final destination to another terminal that has transmitted the request control information to the specific terminal 10. |
