Performance evaluation of ACK-based and NAK-based flow control mechanisms for reliable multicast communications

In this paper, we evaluate the performance of flow control mechanisms for r eliable multicast under several retransmission approaches in terms of scala bility. The mechanisms examined are a window-based flow control mechanism f or ACK-based retransmission approaches and a rate-based How control mechani sm for NAK-based retransmission approaches. Our simulation results show tha t the NAK-based flow control mechanism has better scalability and higher th roughput than the ACK-based flow control mechanism, and the delay incurred by a NAK suppression mechanism does not affect the performance of multicast flow control.