A model-based approach to clock synchronization

Nikolaos Freris, Vivek S. Borkar, P. R. Kumar

Research output: Chapter in Book/Report/Conference proceedingConference contribution

Abstract

In a network of clocks, we consider a given reference node to determine the time evolution t. We introduce and analyze a stochastic model for clocks, in which the relative speedup of a clock, called the skew, is characterized by some given stochastic process. We study the problem of synchronizing clocks in a network, which amounts to estimating the instantaneous relative skews and relative offsets by exchange of time-stamped packets across the links of the network. We present a scheme for obtaining measurements in a communication link. We develop an algorithm for optimal filtering of measurements across a link (i, j) in order to estimate the logarithm of the relative speedup of node j with respect to node i, and we further study some implementation issues. We also present a scheme for pairwise offset estimation based on skew estimates. We study the properties of our algorithms and provide theoretical guarantees on their performance. We also develop an online centralized model-based asynchronous algorithm for optimal filtering of the time-stamps in the entire network, and an efficient distributed suboptimal scheme.

Original languageEnglish (US)
Title of host publicationProceedings of the 48th IEEE Conference on Decision and Control held jointly with 2009 28th Chinese Control Conference, CDC/CCC 2009
Pages5744-5749
Number of pages6
DOIs
StatePublished - Dec 1 2009
Event48th IEEE Conference on Decision and Control held jointly with 2009 28th Chinese Control Conference, CDC/CCC 2009 - Shanghai, China
Duration: Dec 15 2009Dec 18 2009

Other

Other48th IEEE Conference on Decision and Control held jointly with 2009 28th Chinese Control Conference, CDC/CCC 2009
CountryChina
CityShanghai
Period12/15/0912/18/09

Fingerprint

Clock Synchronization
Clocks
Synchronization
Model-based
Skew
Optimal Filtering
Speedup
Vertex of a graph
Asynchronous Algorithms
Timestamp
Stochastic models
Random processes
Logarithm
Estimate
Instantaneous
Telecommunication links
Stochastic Model
Stochastic Processes
Pairwise
Entire

Keywords

  • Clock Offsets
  • Clock Skews
  • Clock Synchronization
  • Distributed Systems
  • Filtering and Estimation
  • Network Delays
  • Networked control
  • Sensor Networks

ASJC Scopus subject areas

  • Control and Systems Engineering
  • Modeling and Simulation
  • Control and Optimization

Cite this

Freris, N., Borkar, V. S., & Kumar, P. R. (2009). A model-based approach to clock synchronization. In Proceedings of the 48th IEEE Conference on Decision and Control held jointly with 2009 28th Chinese Control Conference, CDC/CCC 2009 (pp. 5744-5749). [5399516] https://doi.org/10.1109/CDC.2009.5399516

A model-based approach to clock synchronization. / Freris, Nikolaos; Borkar, Vivek S.; Kumar, P. R.

Proceedings of the 48th IEEE Conference on Decision and Control held jointly with 2009 28th Chinese Control Conference, CDC/CCC 2009. 2009. p. 5744-5749 5399516.

Research output: Chapter in Book/Report/Conference proceedingConference contribution

Freris, N, Borkar, VS & Kumar, PR 2009, A model-based approach to clock synchronization. in Proceedings of the 48th IEEE Conference on Decision and Control held jointly with 2009 28th Chinese Control Conference, CDC/CCC 2009., 5399516, pp. 5744-5749, 48th IEEE Conference on Decision and Control held jointly with 2009 28th Chinese Control Conference, CDC/CCC 2009, Shanghai, China, 12/15/09. https://doi.org/10.1109/CDC.2009.5399516
Freris N, Borkar VS, Kumar PR. A model-based approach to clock synchronization. In Proceedings of the 48th IEEE Conference on Decision and Control held jointly with 2009 28th Chinese Control Conference, CDC/CCC 2009. 2009. p. 5744-5749. 5399516 https://doi.org/10.1109/CDC.2009.5399516
Freris, Nikolaos ; Borkar, Vivek S. ; Kumar, P. R. / A model-based approach to clock synchronization. Proceedings of the 48th IEEE Conference on Decision and Control held jointly with 2009 28th Chinese Control Conference, CDC/CCC 2009. 2009. pp. 5744-5749
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