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Probabilistic Clock Synchronization in Distributed Systems
May 1994 (vol. 5 no. 5)
pp. 474-487

Presents and analyzes a new probabilistic clock synchronization algorithm that can guarantee a much smaller bound on the clock skew than most existing algorithms. The algorithm is probabilistic in the sense that the bound on the clock skew that it guarantees has a probability of invalidity associated with it. However, the probability of invalidity may be made extremely small by transmitting a sufficient number of synchronization messages. It is shown that an upper bound on the probability of invalidity decreases exponentially with the number of synchronization messages transmitted. A closed-form expression that relates the probability of invalidity to the clock skew and the number of synchronization messages is also derived.

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Index Terms:
Index Termssynchronisation; distributed processing; probability; clock synchronization; distributedsystems; clock skew; synchronization messages; probability of invalidity; deterministicalgorithm; master-slave scheme; probabilistic algorithm; time transmission protocol
K. Arvind, "Probabilistic Clock Synchronization in Distributed Systems," IEEE Transactions on Parallel and Distributed Systems, vol. 5, no. 5, pp. 474-487, May 1994, doi:10.1109/71.282558
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