INFORMATION AND COMMUNICATION ENGINEERS Protocol Specification-based Intrusion Detection System for VoIP

Abstract We propose an architecture of Intrusion Detection System (IDS) for VoIP using a protocol specification-based detection method to monitor the network traffics and alert administrator for further analysis and countermeasure for suspicious activities. The protocol behaviors and their interactions are described by state machines. The traffics that behave differently from the standard specifications are considered to be suspicious. The IDS has been implemented and simulated using OPNET modeler, and verified to detect attacks