An apparatus is configured to generate a reference model of a bridged network representing a plurality of nodes in the bridged network, wherein each of the plurality of nodes implements a loop-free topology algorithm; determine an expected data path based on the reference model of the bridged network; receive information pertaining to an actual data path in the bridged network; and compare the expected data path based on the reference model and the actual data path in the bridged network to identify a divergence point.