Precision Time Protocol (PTP)

Support for timing and synchronization Timing (PTX10008)—We support G.8273.2 and G.8275.1 precision time protocols (PTP) profiles over link aggregation group (LAG) on PTX10008 routers. Packet-based timing relies on time stamp packets inserted in the data stream. Time stamps are inserted at the master node where a stratum 1 traceable reference is available, and then extracted at the slave clock where the synchronized frequency or phase reference is needed. In PTP, only slave nodes that require precise frequency synchronization need to incorporate the timing extraction circuitry, and the rest of the packet network can remain asynchronous, which is a key advantage over over physical layer timing methods (for example, SyncE) that need synchronous timing circuitry at every node. Packet-based timing can also transmit both frequency accuracy and phase information, which is essential in applications such as wireless networks (e.g., LTE, 5G - class-C, TSN for URLLC applications), while SyncE is only capable of transmitting frequency accuracy. The feature also support interoperability with the other existing PTX10008 line cards.

[See PTP over Ethernet Overview and G.8275.1 Telecom Profile.]