Time synchronization method, first node, second node, and network

A time synchronization method applied to a second node provided with at least one input port connected to an output port of a first node via an out-of-band synchronization link and at least one additional input port connected to a third node via an in-band synchronization link, comprising:

• receiving out-of-band time synchronization information sent by the first node and in-band time synchronization information sent by at least one third node, wherein the out-of-band time synchronization information comprises a grandmaster clock identity of the first node;
• determining, in response to a case where the grandmaster clock identity of the first node is an identity of the second node, one of all third nodes as a preferred node according to the in-band time synchronization information, and synchronizing time of the second node with time of the preferred node;
• and
• determining, in response to a case where the grandmaster clock identity of the first node is not the identity of the second node, one node among the first node and all the third nodes as a preferred node according to the out-of-band time synchronization information and the in-band time synchronization information, and synchronizing the time of the second node with time of the preferred node,
• wherein the out-of-band time synchronization information further comprises a priority level 1, a priority level 2, and a hop count of the first node.

A second node provided with at least one input port connected to an output port of a first node via an out-of-band synchronization link and at least one additional input port connected to a third node via an in-band synchronization link, comprising:

• a receiving module configured to receive out-of-band time synchronization information sent by the first node and in-band time synchronization information sent by at least one third node, wherein the out-of-band time synchronization information comprises a grandmaster clock identity of the first node;
• a first processing module configured to determine, in response to a case where the grandmaster clock identity of the first node is an identity of the second node, one of all third nodes as a preferred node according to the in-band time synchronization information, and synchronize time of the second node with time of the preferred node;
• and
• a second processing module configured to determine, in response to a case where the grandmaster clock identity of the first node is not the identity of the second node, one node among the first node and all the third nodes as a preferred node according to the out-of-band time synchronization information and the in-band time synchronization information, and synchronize the time of the second node with time of the preferred node,
• wherein the out-of-band time synchronization information further comprises a priority level 1, a priority level 2, and a hop count of the first node.