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Bus arbitration plays an important role in resolving contention and conflict at a shared resource. Six protocols employed in bus arbitration are discussed, namely, static priority, equal or random priority, rotating priority, dynamic priority, the FIFO based system, and batch protocol. Analytical techniques are used to evaluate the protocols for simple situations. Both the average access time and the degree of fairness of the various protocols are examined. It is shown that for simple situations the choice of a protocol has no effect on the average access time, although it can result in certain processors being favored at the expense of others. For more complex situations, protocol simulation is used where it is assumed that each processor is a Poisson process, but the request rates of the various processors differ from one another. In this type of situation it is shown that different protocols have different average access times.