A communication system in which when judging to have received an RRC message from a communication terminal device, a base station device, for example, HeNB checks an MTCD indicator to be mapped to the received RRC message. Then, when judging that the UE that has transmitted the RRC message received is an MTCD being a device for machine type communication (MTC) from the checked MTCD indicator, the HeNB performs a concentration process on the data from the MTCD to the core network.