Patent ID: 8204030

Claim:
A communication method performed by a communication terminal device, the method comprising: establishing, by a control portion of the communication terminal device, a session with one or two or more other communication terminals according to a set content stored in a memory of the communication terminal device before it is changed in a case where a change request for own set information about a radio communication is received; notifying, by a radio communication processing portion of the communication terminal device, a set content to be changed to the one or two or more other communication terminals with which the session is established; changing, by the control portion, the own set information from the set content before it is changed to the set content to be changed; returning, by the control portion, the own set information to the set content before it is changed in a case where a response is not received from at least one of all other communication terminals notified in the notifying before a predetermined period has elapsed since the changing; and transmitting, by the radio communication processing portion, a message informing a success of a radio communication to all the other communication terminals in a case where responses are received from all the other communication terminals notified in the notifying before the predetermined time has elapsed since the changing, wherein the set content to be changed and change timing thereof, and a waiting period for the message since the change timing has elapsed for returning the set information to the set content before it is changed in a case where the message is not received within the period, are notified in the notifying.