Controller-based network device timing synchronization

A controller that manages a network of a plurality of network devices, the controller comprising:

• one or more databases configured to store topology information for the network;
• a time synchronization module configured to determine timing flow roles for one or more ports of each of the plurality of network devices based on the topology information for the network;
• one or more network device protocol interfaces, wherein each of the network device protocol interfaces is configured to output a plurality of messages to one or more of the plurality of network devices, wherein each of the plurality of messages specifies settings information to assign the determined timing flow roles to one or more ports of the respective network device of the plurality of network devices,
• wherein the one or more network device protocol interfaces is configured to receive from each of the plurality of network devices, timestamp information obtained by the plurality of network devices exchanging time synchronization protocol messages with one another,
• wherein the time synchronization module is configured to determine, based on the timestamp information, a respective clock offset for each of the plurality of network devices, and
• wherein the one or more network device protocol interfaces is configured to output the respective clock offsets to update a respective timing clock of each of the plurality of network devices.

A system comprising:

• a plurality of network devices;
• and
• a network controller that manages a network that includes the plurality of network devices, the network controller comprising:
• one or more databases configured to store topology information for the network;
• a time synchronization module configured to determine timing flow roles for one or more ports of each of the plurality of network devices based on the topology information for the network wherein the timing flow roles indicate an orientation of the ports relative to a grand master clock in a timing flow associated with a time synchronization protocol;
• and
• one or more network device protocol interfaces, wherein each of the network device protocol interfaces is configured to output a plurality of messages to the plurality of network devices, wherein each of the plurality of messages specifies settings information to assign the determined timing flow roles to one or more ports of the respective network device of the plurality of network devices,
• wherein a network device of the plurality of network devices comprises:
• an interface configured to receive, from the network controller, a message that specifies settings information to assign timing flow roles to one or more ports of the network device, wherein the timing flow roles indicate an orientation of the ports relative to a grand master clock in a timing flow associated with a time synchronization protocol;
• and
• a time synchronization protocol module configured to set the ports with respective timing flow roles according to the settings information, and, responsive to receiving the message and by the network device, exchange time synchronization protocol messages with one or more neighboring network devices to obtain timestamp information,
• wherein the time synchronization protocol module is configured to send, to the network controller, the timestamp information obtained by exchanging the time synchronization protocol messages,
• wherein the time synchronization module of the network controller is configured to determine, based on the timestamp information, a respective clock offset for each of the plurality of network devices, and wherein the one or more network device protocol interfaces is configured to output the respective clock offsets to update a respective timing clock of each of the plurality of network devices.

A method comprising:

• determining, by a network controller that manages a frequency-assisted timing network of a plurality of network devices, timing flow roles for one or more ports of each of the plurality of network devices based on topology information for the network, wherein the timing flow roles indicate an orientation of the ports relative to a grand master clock in a timing flow associated with a time synchronization protocol,
• wherein determining the timing flow roles comprises determining common timing flow roles for (i) a first time synchronization control protocol for determining a timing frequency and (ii) a second time synchronization control protocol for determining a timing phase;
• outputting, by the network controller, a plurality of messages to one or more of the plurality of network devices, wherein each of the plurality of messages specifies settings information to assign the determined timing flow roles to one or more ports of the respective network device of the plurality of network devices;
• determining, by the network controller and based on timestamp information received from one of the plurality of network devices, a respective clock offset relative to a reference time of the grand master clock for each of the plurality of network devices;
• and
• outputting, by the network controller, the respective clock offsets to update a respective timing clock maintained by each of the plurality of network devices.