CONTROL DEVICE AND CONTROL METHOD

To acquire a notification signal from a relay device that gives notice of the communication amount of a user terminal with an appropriate number of signals regardless of the increase or decrease in the communication amount of the user terminal.SOLUTION: A policy control device 20 includes: an acquisition unit 231 that acquires the communication amount from a relay device that gives notice of the communication amount when the communication volume of an accommodated user terminal exceeds a communication volume threshold; a calculation unit 232 that calculates the communication speed using the communication amount in the past certain period including at least the communication amount acquired by the acquisition unit 231 this time, and calculates the communication amount threshold on the basis of the calculated communication speed; and a notification unit 233 that gives notice the communication amount threshold calculated by the calculation unit 232 to the relay device.SELECTED DRAWING: Figure 4 【課題】ユーザ端末の通信量を通知する中継装置からの通知信号を、ユーザ端末の通信量の増減によらず、適切な信号数で取得することができる。【解決手段】ポリシー制御装置２０は、収容するユーザ端末の通信量が通信量閾値を超えた場合に、通信量を通知する中継装置から、通信量を取得する取得部２３１と、取得部２３１が今回取得した通信量を少なくとも含む過去の一定期間の通信量を用いて通信速度を算出し、算出した通信速度を基に通信量閾値を算出する算出部２３２と、算出部２３２が算出した通信量閾値を中継装置に通知する通知部２３３と、を有する。【選択図】図４