Data transmitting method for machine type communication service and mobile communication system using the same

A mobile communication system that provides a machine type communication (MTC) service, the mobile communication system comprising:

• at least one MTC device subscribing to a multicast service, recognizing at least one wirelessly announced multicast service, and performing joining a desired multicast service;
• a broadcast multicast-service center starting a session for the multicast service and announcing the start of the session as the MTC device performs joining the service;
• and
• a mobility management entity receiving a notification of the session start from the broadcast multicast-service center, recognizing a position of an MTC device belonging to a group that will receive the multicast service, and triggering a paging for a base station corresponding the position of the MTC device;
• a base station receiving a paging message from the mobility management entity and performing group paging for at least one device that will receive the multicast service, receiving a response message as a response to the group paging and allocating necessary resources to the device that will receive the multicast service,
• wherein, in a case in which there is no data to be transmitted in relation to the multicast service for a previously set period of time, the broadcast multicast-service center stops the session, and the MTC device releases resources allocated to the session and performs service deactivation to leave the joined multicast service,
• wherein in a case in which the MTC device performs the joining to transmit collected data information, the MTC device transmits the collected data information to a network, and performs service leaving.