Fault tolerant clock network

TLDR: In this paper, a fault tolerant and redundant grand master clock scheme was proposed to reduce or eliminate precision time transition caused by a network link or device failure, where the primary and backup clocks may be concurrently operated.

Abstract: Fault tolerant and redundant grand master clock scheme may reduce or eliminate precision time transition caused by a network link or device failure. A primary synchronization message may be sent by a primary grandmaster clock and one or more backup synchronization message may be sent by respective backup grandmaster clocks. The primary and backup grandmaster clocks may be concurrently operated. The primary and backup synchronization messages may be sent to an end station over a network. The end station may derive a local clock based on one, some, or all of the received messages. The end station may or may not distinguish between the messages based on the clock source. The end station may validate messages received from a particular clock source.