Performance of a crosspoint buffered ATM switch fabric

The authors present a queuing analysis and a simulation study of banyan switch fabrics based on 2×2 switching elements with crosspoint buffering. In particular, the results apply to the PHOENIX switching element based banyan fabrics. The results indicate that crosspoint buffering provides throughput approaching the offered load under uniform traffic conditions. The effect of bursty traffic on the performance of the switch is studied. It is shown that a speedup factor of three or more is required to achieve acceptable delay and packet loss probability. It is also shown that the amount of buffer space required per port increases linearly with the burst size for a desired packet loss performance. For a given burst size the packet loss rate decreases exponentially as the buffer size is increased. The impact of crosspoint buffering and shared buffering in the switching elements on the performance of the banyan fabric is analyzed