In this paper we are concerned with an operational approach to fairness, the problem of defining and generating the fair execution sequences of a concurrent language. One solution invokes two semantic levels: one level (the positive) prescribes the finite and infinite execution sequences without regard to their fairness while the other (the negative) filters out the unfair ones. The first level is given as a set of generative rules whereas the second is encoded as a definition of fair execution sequence. Entirely positive approaches have been proposed which appeal to random assignment. Here we offer an alternative positive approach for a subset of Milner's CCS. We show that rules can be given for generating just the fair sequences which avoid random assignment.
KeywordsInformation System Operating System Data Structure Communication Network Information Theory
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