A method for profiling network traffic of a network. The method includes identifying a training set having captured payloads corresponding to a set of flows associated with a network application, determining a set of signature terms from the training set, representing a portion of the captured payloads as regular expressions, representing a regular expression as a path in a modified term transition state machine (MTTSM) including states coupled by at least a link that is assigned a signature term, and analyzing, based on the MTTSM, a flow separate from the set of flows and associated with a server in the network to determine the server as executing the network application.