A system and method for monitoring, modeling and assessing networked devices. A continuous device profiling (CDP) system builds and maintains device-specific and network-specific behavioral models based on observation of network traffic. The behavioral models may be used for network management, detecting misconfigured or malware infected devices, performing network asset inventory, network access control, network discovery in support of network integration, and information security incident response management. CDP models and monitors the active roles that devices assume on the network based on a set of matching profiles, monitors transitions between roles, and triggers corrective action when role transitions violate the policies of the network.