Communication terminal device, communication system, communication method, and program

A communication system comprising a plurality of communication terminal devices for forming a group and performing communication within the group,

• the communication terminal devices each including:
• a transmission unit which transmits at least an annunciation signal and/or a packet including a communication parameter to the at least one other communication terminal device;
• a reception unit which receives at least an annunciation signal and/or a packet including a communication parameter i from the at least one other communication terminal device;
• and
• a control unit which exercises communication control in accordance with a communication parameter pertaining to a network, the control unit being capable of responding to a communication parameter, different from a communication parameter which is being used in communication in progress, included in a packet received by the reception unit.

A communication method for forming a group with at least one other communication terminal device and performing communication within the group, the method comprising:

• transmitting at least an annunciation signal and/or a packet including a communication parameter to the at least one other communication terminal device;
• receiving at least an annunciation signal and/or a packet including a communication parameter from the at least one other communication terminal device;
• exercising communication control in accordance with a communication parameter pertaining to a network;
• and
• responding to a communication parameter, different from a communication parameter which is being used in communication in progress, included in a packet received, thereby exercising communication control in accordance with a communication parameter.

A computer program written in a computer-readable format so that a computer system executes processing for forming a group with at least one other communication terminal device and performing wireless communication within the group, the program comprising:

• transmitting at least an annunciation signal and/or a packet including a communication parameter to the at least one other communication terminal device;
• receiving at least an annunciation signal and/or a packet including a communication parameter from the at least one other communication terminal device;
• exercising communication control in accordance with a communication parameter pertaining to a network;
• and
• responding to a communication parameter, different from a communication parameter which is being used in communication in progress, included in a packet received, thereby exercising communication control in accordance with a communication parameter.