r5 - 2012-08-14 - 11:42:40 - ThiagodeFreitasYou are here: NTP >  Dev Web > GoogleSummerOfCode > GSoC2012ClockModels
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Clock Models (GSoC 2012)


The goal of this project is to analyze the usefulness of different clock models for NTP, contributing for an enhanced performance. The goal is to use filtering techniques to analyze 2 issues. The first is a parameter that provides an explicit connection between the polling interval and the accuracy of the synchronization process. The second issue is a more sophisticated model for the performance of the clock on the local system and for the network delay.

Related Items: ClockAlgorithms


Current Code may be obtained at :



  1. Write a program that computes the Allan deviation of a local clock using the NTP data as the time differences. The NTP data would not adjust the local clock, so that the result would be the statistical performance of the combination.
  2. Graphical representation of the data.
  3. Run the estimator for about a week.
  4. GUI Development
  5. Calculate the Allan Deviation, the Histograms, the Residuals
  6. Eliminate Bad-Measurements using the Allan Deviation of the Middle of the Data
  7. Dr. Levine algorithm for eliminating outliers
  8. Ransac algorithm for eliminating outliers
  9. Allan Deviation of the corrected sampled data
  10. Explanation of the results obtained. Small Report to Dr. Levine


Date Task Description % Done
04-23 Community Bonding Students get to know mentors, read documentation, get up to speed to begin working on their projects. choice-yes
05-21 Coding Begins Students begin coding for their GSoC projects choice-yes
05-22 1 Code the program proposed by Dr. Levine choice-yes
05-28 2 and 3 Run the estimator for one week choice-yes
06-09 4   choice-yes
06-15 5   choice-yes
06-23 6   choice-yes
07-09 BO Midterm Evals Mentors and students can begin submitting mid-term evaluations.  
07-13 EO Midterm Evals Mid-term evaluations deadline.  
07-21 7   choice-yes
07-28 8   choice-yes
08-04 9   choice-yes
08-15 10    
08-13 Wrap-up Suggested "Pencils Down" date. Take a week to scrub code, write tests, improve documentation, etc.  
08-20 Firm "Pencils Down" Mentors, students and organization administrators can begin submitting final evaluations to Google.  
08-24 Final Evaluation Final Evaluations Deadline  
08-27 Final Results Final Results Announced  
08-31 Code Samples Students begin uploading code samples  

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