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Adaptive Estimation of Clock Skew and Different Types of Delay in the Internet Network

  • Jacob Benesty
Part of the Signals and Communication Technology book series (SCT)

Abstract

The end-to-end delay is often used to analyze network performance. There are different types of delay in the network: (artificial) delay due to unsynchronized clocks, transmission and propagation delays, and delay jitter. First, we show how to obtain a least-squares estimate of the clock skew (i.e. difference between the sender and receiver clock frequencies) and the fixed delay. We then show that the linear programming algorithm proposed elsewhere to estimate the clock ratio is equivalent to the maximum likelihood estimator if the delay jitter is modeled as an independent, identically distributed random process with an exponential probability density function. Finally, we show how to estimate the delay jitter and propose an unbiased recursive least-squares algorithm to estimate the clock skew and fixed delay.

Keywords

Clock Frequency Adaptive Estimation Delay Measurement Delay Jitter Clock Drift 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

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Copyright information

© Springer-Verlag Berlin Heidelberg 2003

Authors and Affiliations

  • Jacob Benesty
    • 1
  1. 1.Bell LaboratoriesLucent TechnologiesMurray HillUSA

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