In one embodiment, a method for managing a Voice over IP (VoIP) network includes collecting a first set of data from a first source of network performance management data, each data item in the first set of data corresponding to a call made using the VoIP network; collecting a second set of data from a second source of network performance management data, each data item in the second set of data corresponding to a call made using the VoIP network and being of a different type than the first set of data; correlating the first set of data and the second set of data such that a data item from the first set of data is matched with a data item from the second set of data that corresponds to a common call made over the VoIP network; and outputting a performance report based on the correlating.