High performance cell scheduling algorithm in broadband multicast switching systems

In this paper, a multicast cell scheduling algorithm with input queue is proposed in ATM multicast switching systems. Therefore, HOL blocking may occur due to FIFO input queuing discipline. To avoid HOL blocking, our algorithm relaxes the strict FIFO queueing discipline for input queue to increase its throughput. But the order of cell sequence is still preserved. In our cell scheduling algorithm, every multicast cell is only watched one time, but in the window policy every cell will be watched more than two times in average. The simulated result shows that our proposed scheme gets high performance with respect to cell loss probability, required buffer size, and waiting delay. Moreover, the maximum throughput of our proposed algorithm can be obtained almost up to 0.997 and is independent of the switch size and input load. The time complexity of our proposed scheme is also analyzed and can be acceptable. Hence, Our cell scheduling algorithm is an efficient scheme of the ATM switching system.