In an embodiment, a computer-implemented method compares metrics from different data flows to detect flaws in collection of data describing operation of a network. The method uses a first network data collection technique to collect a first metric describing a characteristic of a network interface. Using a second network data collection technique different from the first network data collection technique, a second metric describing the characteristic of the network interface is collected. The first metric is compared with the second metric to determine whether the first and second metrics are incongruous. When the first and second metrics are determined to be incongruous, a flaw is detected to exist in the first or second network data collection techniques.