A communication device for providing a service in response to a request from a mobile object includes: a reception unit for receiving identification information from the mobile object; an authentication unit for performing authentication of the identification information; a service provision unit for providing the service to a mobile object having legitimately registered identification information on the basis of a result of authentication performed by the authentication unit; a mobile object detection unit for detecting movement of the mobile object; a communication device detection unit for detecting another communication device in the vicinity of the mobile object on the basis of a result of detection performed by the mobile object detection unit; and an instruction unit for causing the other communication device detected by the communication device detection unit to provide a service equivalent to the service to the mobile object without performing authentication for the mobile object.