A CP parameter includes a periodic communication indicator, a communication duration time, a periodic time, a scheduled communication time, and a stationary indication. Further, a quota, rate control, and a charging policy may be added to the CP parameter. The AS 130 may determine a value of at least one of the quota, the rate control, and the charging policy, and set the determined value in the set chargeable party request message as a CP parameter. Moreover, the AS 130 may set, in the set chargeable party request message, only a changed parameter, out of the periodic communication indicator, the communication duration time, the periodic time, the scheduled communication time, the stationary indication, the quota, the rate control, and the charging policy. Note that the AS 130 may determine a tariff, and include the tariff in the CP parameter.