Performance analysis of the pi-persistent protocol in unidirectional bus networks

The pi-persistent medium access protocol is an attractive solution for high-speed time-slotted unidirectional bus networks. This protocol, with its very simple flow control mechanism allowing station i to access empty slots with station-dependent probability pi, has been seen as an alternative for solving fairness problems associated with the original IEEE 802.6 standard for the distributed queue dual bus (DQDB) for high-speed networks. In this paper we analyze the main aspects of the fairness provision mechanism employed in the pi-persistent protocol.