Abstract: Control of a packet communications network in a fixed network used by a mobile communications network is performed. (1) A communication hold mode is set for a user when the traffic volume of the user's transmission or reception of a packet per fixed time period is less than a predetermined value. The communication hold mode is defined as “although the network resources are released once, a mobile station and a gateway center at an interface with an external network behave to the user side and the external side as though the communication hold mode were maintained”. (2) When the user in the communication hold mode restarts the transmission of a packet, the mobile station automatically carries out a recall processing without the intervention of the user, and re-establishes the communication up to the gateway carrier.