Patent attributes
The present invention generally relates to methods and apparatuses for event-driven and stateless precision time transfer. In one embodiment, a master device creates and launches Precision Timing Protocol (PTP) Sync packets, as well as Follow-up packets in the case of two-step clock operation, on an event-driven basis in response to the receipt of a Delay Request message from a slave device, rather than based on scheduling performed by the master device. Doing so reduces the load on the master device and permits the master to serve a larger number of slave devices. In addition, PTP Announce messages, which are not used for calculating the time offset between master and slave devices, may be sent in response to some Delay Request messages using an adjustable sampling rate (e.g., 1 every x Delay Request messages).
