A Posteriori Agreement for Clock Synchronization on Broadcast Networks

We present a clock synchronization algorithm, dubbed a posteriori agreement, based on a new variant of the well-known convergence non-averaging technique. By exploiting an obvious characteristic of broadcast networks, the e ect of message delivery delay variance is largely reduced. In consequence, the precision achieved by the algorithm is drastically improved. Accuracy preservation is near to optimal. Our solution, however, does not require the use of dedicated hardware. A shorter version of this report was published in the Digest of Papers, The 22th International Symposium on Fault-Tolerant Computing, July, 1992, Boston USA, c 1992 IEEE Instituto de Engenharia de Sistemas e Computadores, R. Alves Redol, 9 6 1000 Lisboa Portugal, Tel.+351-1-3100000 This work has been supported in part by the CEC, through Esprit Project 1226 DELTA-4, and JNICT, through Programa Ciência.

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