A virtual-screen setup unit sets up a virtual screen in a seam of images captured by an image capturing unit, the virtual screen being orthogonal to a road surface and extending in a direction from a near side to a far side of the vehicle. The method comprises the steps of initiating a connection by a client to a server to form a session, responding by said server to said client indicating that said connection has been successfully completed, submitting a request by said client to said server for service, responding by said server to said client by providing said service and terminating the connection by said client. The base end is pivotally coupled to the fixed support pole and the traveling end is pivotally coupled to the backboard assembly.