Managing network traffic to improve availability of network services by classifying network traffic flows using flow-level statistical information and machine learning estimation, based on a measurement of at least one of relevance and goodness of network features. Also, determining a network traffic profile representing applications associated with the classified network traffic flows, and managing network traffic using the network traffic profile. The flow-level statistical information includes packet-trace information and is available from at least one of Cisco NetFlow, NetStream or cflowd records. The classification of network flows includes tagging packet-trace flow record data based on defined packet content information. The classifying of network flows can result in the identification of a plurality of clusters based on the measurement of the relevance of the network features. Also, the classification of network traffic can use a correlation-based measure to determine the goodness of the network features.