To reduce a hardware amount and to accelerate an access speed.

SCPs(service control points) 20, 21 and 22 are provided corresponding to respective call services (for instance, free phone service). In the respective SCPs, only a function required for realizing the corresponding call service is held. Thus, a data amount held in the respective SCPs is reduced and the hardware amount is reduced. Since the data amount to be held in the respective SCPs can be less, the respective SCPs are realized by a semiconductor memory. Thus, the access speed to the respective SCPs is accelerated and the throughput of the call service is improved.