Internet protocol TV (IPTV) is one of the most important multimedia applications for next-generation networks. IPTV provides triple-play services that require high-speed access networks with the functions of multicasting and quality of service (QoS) guarantees. Among access networks, Ethernet passive optical networks (EPONs) are regarded as among the best solutions to meet higher bandwidth demands. In this paper, we propose a new architecture for multicasting live IPTV traffic in EPONs. The proposed mechanism involves assigning a unique logical link identifier to each IPTV channel. To manage multicasting, a table in the optical line terminal (OLT) and in each optical network unit (ONU) is constructed. These tables are maintained in the reconciliation sublayer to deliver the IPTV traffic. We extend the message passing of the original real-time streaming protocol (RTSP), called the extended RTSP (ERTSP), to handle the IPTV requests. A mechanism is proposed to handle the IPTV requests as intra traffic in the ONU without sending the request to the OLT. Handling the live IPTV channel as intra traffic can save bandwidth in the feeder fiber and increase the system throughput. Simulation results show that our proposed architecture can improve the system performance and QoS metrics in terms of packet delay, jitter, system throughput, and packet loss.