Method and apparatus for multicast in communication system

A method performed by a service management apparatus in a wireless communication system, the method comprising:

• receiving, from a user plane function (UPF), an internet group management protocol (IGMP) join message including a multicast internet protocol (IP) address and an identification (ID) of a multicast session between a terminal and the UPF;
• generating information on a multicast tunnel between the UPF and a software defined network (SDN) switch based on the IGMP join message, wherein the information on the multicast tunnel includes an ID of the multicast tunnel and an IP address of the multicast tunnel;
• transmitting, to the UPF, a multicast tunnel generation request message including the ID of the multicast session and the information on the multicast tunnel;
• generating a service rule for transmitting multicast packets;
• transmitting the service rule to a SDN controller for controlling the SDN switch based on the service rule;
• and
• transmitting, to the SDN switch through the SDN controller, a multicast service request message including the multicast IP address and the information on the multicast tunnel,
• wherein the multicast IP address is used to transmit multicast packets duplicated at the SDN switch from the SDN switch to the UPF through the multicast tunnel generated by the SDN switch, wherein the multicast tunnel starts from the SDN switch and terminates at a gateway based on information included in the multicast service request message, and
• wherein the ID of the multicast session is used to transmit the multicast packets duplicated at the SDN switch from the UPF to the terminal through the multicast session.

A user plane function (UPF) in a wireless communication system, the UPF comprising:

• a transceiver;
• and
• at least one processor operably coupled to the transceiver and configured to:
• receive, from a terminal, an internet group management protocol (IGMP) join message with an identification (ID) of a multicast session between the terminal and the UPF,
• transmit, to a service management apparatus, the IGMP join message with the ID of the multicast session between the terminal and the UPF,
• receive, from the service management apparatus, a multicast tunnel generation request message including the ID of the multicast session and information on a multicast tunnel between the UPF and a software defined network (SDN) switch, wherein the information on the multicast tunnel includes an ID of the multicast tunnel and an IP address of the multicast tunnel,
• receive, from the SDN switch, multicast packets duplicated at the SDN switch through the multicast tunnel based on the multicast IP address, wherein the multicast tunnel is generated by the SDN switch, and
• transmit, to the terminal, the multicast packets duplicated at the SDN switch through a downlink of the multicast session, wherein the multicast session is matched with the multicast tunnel based on the ID of the multicast session.