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Unison, canon, and sluggish clocks in networks controlled by a synchronizer

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Abstract

The effect of using a simple synchronizer on the performance of a directed, strongly connected, distributed network, is analysed. In this paper we assume that the time of message transmission is positive but negligible. It is shown that the synchronizer is sufficient to assure that a full rate of computation is achieved in networks with a global clock, in spite of the absence of a global start-up signal. In fact,unison is reached within linear time. A similar phenomenon occurs if there is no global clock, but all local clocks have the same rate. In case the local clocks do not have the same rate, it is shown that the computational rate is not slower than anysluggish clock; i.e., a clock such that between any two of its ticks, every local clock ticks at least once.

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The first author was supported by the Fund for the Promotion of Research at the Technion. The work of the second author was done while he was in the Computer Science Department of the Technion; he is presently visiting the Laboratory for Computer Science, MIT.

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Even, S., Rajsbaum, S. Unison, canon, and sluggish clocks in networks controlled by a synchronizer. Math. Systems Theory 28, 421–435 (1995). https://doi.org/10.1007/BF01185865

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