White Rabbit Fixed Point Calculations

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

Contact

Rens Roosenstein

Parent Projects

White Rabbit

White Rabbit provides **sub-nanosecond accuracy** and picoseconds precision of **synchronization** for large distributed systems

White Rabbit Switch

This page hosts all CERN stable firmware releases for the WR switch, the main component of the [White Rabbit](https://www.ohwr.org/project/white-rabbit) project