Performance Analysis and Comparison Between Multicast and Unicast over Infrastructure Wireless LAN

摘要

Although multicast communication has been widely deployed and extensively studied for several years, it is still difficult to quantitatively compare the performance of multicast and unicast transmission schemes, especially in limited bandwidth environments. This paper presents a simple stochastic Markov model for multicast communication over infrastructure wireless LANs. The model addresses configurations where a variable number of mobile hosts request access to one or more concurrent communication streams. The steady state transition probabilities are derived and used to obtain numerical results for average bandwidth used for streaming transmissions under typical wireless LAN conditions, under both unicast and multicast transmission. Parameters in the model include number of avialable streams, maximum permitted number of sessions, and arrival rates of mobile hosts. The stochastic model and quantitive results can have application to evaluation of proposed designs for multicast service models and protocols.