DISTRIBUTED PROCESSING SCHEME TO SUPPORT IEEE 1588 PTP OVER MULTIPLE PORTS SPANNING A LAG

摘要

A Precision Timing Protocol (PTP) is implemented over a Link Aggregation Group (LAG) formed by multiple ports of a network node, where PTP traffic goes through the same physical link between the network node and a peer network node on both the transmit and return paths. When the network node receives a PTP message that identifies a PTP stream from the peer network node through a given PTP-LAG port, it declares itself as an active port and the other PTP-LAG ports as standby for the PTP stream. The PTP stream is transmitted from the network node to the peer network node through the active port only, to maintain symmetry of the PTP stream's transmission paths between the network node and the peer network node. The network node processes exchanged messages of the PTP stream to perform timing synchronization with the peer network node.