US Patent 11323312 Software-defined network monitoring and fault localization

The disclosure describes techniques for network monitoring and fault localization. For example, a controller comprises one or more processors operably coupled to a memory configured to: receive a first one or more Quality of Experience (QoE) metrics measured by a first probe traversing a first path comprising one or more links; receive a second one or more QoE metrics measured by a second probe traversing a second path comprising one or more links; determine, from the first one or more QoE metrics, that the first path has an anomaly; determine, from the second one or more QoE metrics, that the second path has an anomaly; and determine, in response to determining the first path and the second path has an anomaly, based on the type of metrics and the type of links, that an intersection between the first path and the second path is a root cause of the anomaly.