Patent ID: 8385248

Claim:
A method for providing Multicast and Broadcast Service (MCBCS) in a wireless communication system, the method comprising: receiving, at an Access Service Network Gateway (ASN GW), a leave message from a mobile station to stop being provided with an MCBCS; transmitting, at the ASN GW, a leave indication message to an MCBCS server upon receipt of the leave message, receiving a first leave response message from the MCBCS server according to the leave indication message, and transmitting a leave request message to a base station according to the first leave response message; performing, at the base station, a dynamic service deletion procedure with the mobile station upon receipt of the leave request message, and transmitting a second leave response message to the ASN GW according to the leave request message; and receiving, at the ASN GW, the second leave response message from the base station, transmitting, if the mobile station is the last mobile station within an Multicast and Broadcast Service (MBS) zone, a path deregistration request message to the base station, receiving a path deregistration response message from the base station according to the path deregistration request message, transmitting a multicast tree leave message to the MCBCS server according to the path deregistration response message, and leaving a multicast tree.