The present application relates to the technical field of communications, particularly to a network node, a packet transmission method and a network, and is used to provide a solution of performing time synchronization between network nodes. The solution supports packet encryption, and can guarantee the precision of time synchronization. In the packet sending method provided by the present application, a network node sends a first encrypted packet to another network node, and sends a second encrypted packet to another network node, wherein the second encrypted packet comprises first time stamp information for indicating a first sending moment of the first encrypted packet. By means of the present application, a target network node of an encrypted packet can acquire an accurate sending moment of the encrypted packet, and thus performs time synchronization with a source network node of the encrypted packet.