Performance analysis of multicast flow control algorithms over combined wired/wireless networks

A multipoint flow control framework for data traffic traversing both a wired and wireless network is proposed. A Markov modulated fluid model is used for the receiver to capture the dynamics of the wireless links. We discover that the phase difference of the instantaneous throughput of the receivers is a distinctive feature of multicast connections. The objectives of the multicast flow control algorithms are to cope with the receiver phase difference cost-effectively in addition to the general goals such as maximizing throughput and minimizing delay. Three ad hoc algorithms have been studied: Listen to Slowest Request (LSQ), Source Estimation (SE), and Open Loop Control. A fluid analysis technique is applied to study the effect of receiver phase difference assuming zero delay. The effect of propagation delay is then discussed. Simulation results are presented to verify the analysis for the zero delay case and to compare the performance of the algorithms under non-negligible delay.