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The Accuracy of the Clock Synchronization Achieved by TEMPO in Berkeley UNIX 4.3BSD
July 1989 (vol. 15 no. 7)
pp. 847-853

The authors discuss the upper and lower bounds on the accuracy of the time synchronization achieved by the algorithm implemented in TEMPO, the distributed service that synchronizes the clocks of the University of California, Berkeley, UNIX 4.3BSD systems. The accuracy is shown to be a function of the network transmission latency; it depends linearly upon the drift rate of the clocks and the interval between synchronizations. TEMPO keeps the clocks of the VAX computers in a local area network synchronized with an accuracy comparable to the resolution of single-machine clocks. Comparison with other clock synchronization algorithms shows that TEMPO, in an environment with no Byzantine faults, can achieve better synchronization at a lower cost.

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Index Terms:
upper bounds; clock synchronization; TEMPO; Berkeley UNIX 4.3BSD; lower bounds; distributed service; network transmission latency; VAX computers; local area network; fault tolerant computing; local area networks; synchronisation; Unix
Citation:
R. Gusella, S. Zatti, "The Accuracy of the Clock Synchronization Achieved by TEMPO in Berkeley UNIX 4.3BSD," IEEE Transactions on Software Engineering, vol. 15, no. 7, pp. 847-853, July 1989, doi:10.1109/32.29484
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