ONTIDS: A Highly Flexible Context-Aware and Ontology-Based Alert Correlation Framework

Several alert correlation approaches have been proposed to date to reduce the number of non-relevant alerts and false positives typically generated by Intrusion Detection Systems (IDS). Inspired by the mental process of the contextualisation used by security analysts to weed out less relevant alerts, some of these approaches have tried to incorporate contextual information such as: type of systems, applications, users, and networks into the correlation process. However, these approaches are not flexible as they only perform correlation based on the narrowly defined contexts. information resources available to the security analysts while preserving the maximum flexibility and the power of abstraction in both the definition and the usage of such concepts, we propose ONTIDS, a context-aware and ontology-based alert correlation framework that uses ontologies to represent and store the alerts information, alerts context, vulnerability information, and the attack scenarios. ONTIDS employs simple ontology logic rules written in Semantic Query-enhance Web Rule Language (SQWRL) to correlate and filter out non-relevant alerts. We illustrate the potential usefulness and the flexibility of ONTIDS by employing its reference implementation on two separate case studies, inspired from the DARPA 2000 and UNB ISCX IDS evaluation datasets.