Patent ID: 8441974

Claim:
A method of providing a multicast broadcast service (MBS) from an MBS server to a mobile terminal, the method comprising: creating, by a base station, an MBS registration request message for a program of an MBS that the mobile terminal desires to receive, and transmitting, by the base station, the MBS registration request message to the MBS server that provides the corresponding MBS; receiving, by the base station, an MBS registration response message from the MBS server, the MBS registration response message including a security relationship identifier indicating information on an access authority of the mobile terminal with respect to the program of the MBS; transmitting, by the base station, a request message of a multicast traffic key corresponding to the security relationship identifier to the MBS server according to whether the security relationship identifier included in the MBS registration response message is set or not; and causing, by the base station, the MBS server to perform an authentication process on the mobile terminal, receiving, by the base station, a multicast traffic key response message including the multicast traffic key that is created by performing the authenticating process, storing, by the base station, the multicast traffic key, and transmitting, by the base station, a response message to the mobile terminal to complete a service registering process for receiving the corresponding MBS.