This project focuses on performing, with high precision, the WR PTP calculations in fixed-point arithmetic. This will ensure uniform input parameters, code and precision across all WR implementations. Previously these calculations were done differently in the WR switch and the WR PTP core. The current calculations use a combination of mathematical models for description of this calculation using fixed-point arithmetic without losing precision. This calculation is used in both the WR switch and the WR PTP core.

In the document “Mathematics” the mathematics used for this calculation are explained. These mathematics are used to perform the WR PTP time calculations that are described in:

• White Rabbit Specification v2.0
• IEEE1588-2019 (draft to be published), in particular:
  • 7.4.2: PTP Communication Path delay, PTP Link delay, and delayAsymmetry
  • 16.8.3: Calculation of the delayAsymmetry

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