Problems of the current IGMP mechanism were identified, such as unnecessary periodic probing of hosts and leave latency, which wastes bandwidth and cause more traffic and overhead. Alternative mechanism that preserve the IP multicast model but employ join/leave messages to track local group membership for broadcast LANs (shared medium LANs) was proposed in this paper. We describe the implementation requirements of the new mechanism and compare it to existing one, demonstrating that join/leave approach is uniformly superior for the environment of broadcast LANs. Problems of the current IGMP mechanism were identified, such as unnecessary periodic probing of hosts and leave latency, which was bandwidth and cause more traffic and overhead. Alternative mechanism that preserve the IP multicast model but employ join / leave messages to track local group membership for We describe the implementation requirements of the new mechanism and compare it to existing one, demonstrating that join / leave approach is uniformly superior for the environment of broadcast LANs.