Method for traffic engineering in communications network and controller

A controller in a communications network, wherein the communications network comprises the controller and multiple nodes, the multiple nodes comprise at least one flexible node and a non-flexible node, the at least one flexible node is directly connected to the controller, the at least one non-flexible node is indirectly connected to the controller, and the controller comprises:

• at least one processor;
• and
• a memory storing a plurality of computer executable instructions which, when executed by the at least one processor, cause the controller to:
• determine at least one sampling node in the at least one flexible node and a temporal frequency for traffic sampling;
• instruct the at least one sampling node to perform traffic sampling at the temporal frequency;
• receive sampled traffic data of all sampling nodes obtained during each sampling;
• determine, according to the sampled traffic data obtained during each sampling and information about total traffic of a link in the communications network whose link utilization is greater than a first preset value or less than a second preset value, parameter information for traffic engineering, wherein the information about total traffic of the link is determined based on the sampled traffic data;
• and
• perform traffic engineering control according to the parameter information.