Disclosed is a method of accepting a QoS request for utilizing resources of a network in a predetermined quality. The method receives from a terminal connected to the network a resource unnecessity notification indicating that resource allocated to the terminal has become unnecessary, and holds, as a free resource information, information on a free resource which is a resource notified by the resource unnecessity notification as unnecessary resource. Then, the method receives the QoS request from the terminal, and determines whether the free resource meets the received QoS request or not on the basis of the free resource information. The method allocates the free resource to the terminal when the free resource meets the received QoS request, and transmits information on the allocated free resource to the terminal.