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.

Abstract: Devices implement encapsulation to support link layer preemption. The device may include a encapsulation logic that encapsulates data, such as an Ethernet frame, to produce an encapsulated frame. The encapsulated frame may include an encapsulation element that indicates whether the encapsulated data includes non-preemptible data, such as Distinguished Minimum Latency Traffic (DMLT), or preemptible data. The encapsulated frame may also indicate whether the encapsulated data comprises the last fragment of a preemptible frame.

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.

Abstract: Devices implement encapsulation to support link layer preemption. The device may include a encapsulation logic that encapsulates data, such as an Ethernet frame, to produce an encapsulated frame. The encapsulated frame may include an encapsulation element that indicates whether the encapsulated data includes non-preemptible data, such as Distinguished Minimum Latency Traffic (DMLT), or preemptible data. The encapsulated frame may also indicate whether the encapsulated data comprises the last fragment of a preemptible frame.