A method by a user equipment (UE) supporting a plurality of group communications having different qualities of service (QoSs) in a wireless communication system, the method comprising:
- receiving, from at least one application client having a predetermined address value, traffic for an application server;
- setting a first group associated with the predetermined address value;
- establishing a PDU session for one of the first group associated with the predetermined address value and a second group associated with the application server set by an application function (AF);
- and
- transmitting the traffic to the application server through the generated PDU session.