Abstract: In a communication system, a management device transmits a confirmation request signal requesting confirmation of a state of a terminal device to each of a plurality of terminal devices at the same timing all at once. Each of the terminal devices returns the notification information to the management device together with terminal identification information for identifying the terminal device in a case where there is notification information. The management device identifies the terminal device that has returned the notification information based on the terminal identification information in a case where the notification information is returned from the plurality of terminal devices at the same timing, and individually re-transmits the confirmation request signal to the identified terminal devices at different timings.

Abstract: A vehicle control device mounted on a vehicle has a search signal transmission unit that transmits a search signal for searching a position of a portable device, which remotely operates the control device, a determination unit that determines a bright and dark state of outside of the vehicle, and a storage unit that stores a determination result of the determination unit.

Abstract: A control system has a control device for performing a control of a predetermined process, and a communication device for communicating with the control device. The control device has a first transmission unit for transmitting a request signal requesting for transmission of a response signal to the communication device, a first reception unit for receiving the response signal transmitted through a predetermined procedure from the communication device in response to the request signal transmitted by the first transmission unit, an authentication unit for performing authentication of the communication device using identification information of the communication device contained in the response signal received by the first reception unit and identification information of the communication device registered in advance, and a process executing unit for executing the predetermined process when the authentication of the communication device by the authentication unit is successful.

Abstract: A vehicle control device mounted on a vehicle has a search signal transmission unit that transmits a search signal for searching a position of a portable device, which remotely operates the control device, a determination unit that determines a bright and dark state of outside of the vehicle, and a storage unit that stores a determination result of the determination unit.

Abstract: A control system has a control device for performing a control of a predetermined process, and a communication device for communicating with the control device. The control device has a first transmission unit for transmitting a request signal requesting for transmission of a response signal to the communication device, a first reception unit for receiving the response signal transmitted through a predetermined procedure from the communication device in response to the request signal transmitted by the first transmission unit, an authentication unit for performing authentication of the communication device using identification information of the communication device contained in the response signal received by the first reception unit and identification information of the communication device registered in advance, and a process executing unit for executing the predetermined process when the authentication of the communication device by the authentication unit is successful.