Simulation-Based Performance Analysis of Multicast Transmissions in an 802.11g WLAN

Multicasting at the data link layer is an efficient way for sending data to a group of receivers. IEEE 802.11 has become the de facto standard for wireless LAN. This paper focuses on the throughput versus distance analysis of multicast transmissions in an 802.11g network. Using an accurate simulation model for the MAC and PHY layer, we show that the default transmit mode is not an efficient choice under certain circumstances. UDP transmissions with data payloads close to the maximum transmit unit and transmissions carrying small amounts of data are investigated under different transmission modes and channel models. Simulations have shown that there are several alternatives to Mode 1, which is the default mode for multicast transmissions, when the receivers are not far from the transmitting station.