3 ms·

https://en.wikipedia.org/wiki/Precision_Time_Protocol https://en.wikipedia.org/wiki/Precision_Time_Protocol

• karmakaze 5y ago
  > The best master clock (BMC) algorithm performs a distributed selection of the best candidate clock based on the following clock properties: (IEEE 1588-2008 uses a hierarchical selection algorithm based on the following properties, in the indicated order:[8]:Figure 27) > Priority 1 – the user can assign a specific static-designed priority to each clock, preemptively defining a priority among them. Smaller numeric values indicate higher priority. > Class – each clock is a member of a given class, each class getting its own priority. Accuracy – precision between clock and UTC, in nanoseconds (ns) > Variance – variability of the clock > Priority 2 – final-defined priority, defining backup order in case the other criteria were not sufficient. Smaller numeric values indicate higher priority. > Unique identifier – MAC address-based selection is used as a tiebreaker when all other properties are equal. Only useful if you trust the data: Class, Accuracy, and Variance (which seems to be a self-measured estimate).