Patent ID: 8000658

Claim:
A communicating apparatus comprising: a communicating unit that exchanges a message with an external device using a wireless signal; a communication control unit that transmits a detection message for detecting a distance to the external device to the external device and receives a reply message in response to the detection message from the external device, via the communicating unit; a first calculating unit that calculates the distance based on a response time required to receive the reply message; a determining unit that determines whether the distance is smaller than a first threshold; an establishing unit that establishes, when the distance is determined to be smaller than the first threshold, an encryption invalidated communication in which the message is not encrypted with the external device; and a second calculating unit that calculates, when the distance is determined to be smaller than the first threshold, a minimum transmission power of the wireless signal for performing a communication with the external device at the distance, wherein the communication control unit controls the communicating unit to transmit the message to the external device using the wireless signal with the minimum transmission power.