r2 - 2013-07-13 - 17:41:38 - RahulKatareYou are here: NTP >  Dev Web > GoogleSummerOfCode > GSoC2013StartupAnalysisRahul > GSoC2013StartupAnalysisRahulDesign
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Work Page

Initial Discussion

  • We have data from a single hosts, some 'p' no. of packets. Task is to find offset and drift(frequency).
  • One of the Idea to do this is to plot (ourtime, histime) where ourtime - Time at our machine, histime - time returned from the host ( which can be calculated from t1/t2/t3/t4 timestamps returned from the host).
  • If we fit a linear regression line in this plot, slope will give us the frequency estimate.
  • Another idea is to do a plot of (0, offset1), (1, offset2) .... and similar calculations can be done.
  • Wifi connections have more 'jitter', linear fit may not be the best option here, some thoughts need to be made in this area later.

-- RahulKatare - 2013-06-08

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