EMERALD: Event Monitoring Enabling Responses to Anomalous Live Disturbances

The EMERALD (Event Monitoring Enabling Responses to Anomalous Live Disturbances) environment is a distributed scalable tool suite for tracking malicious activity through and across large networks. EMERALD introduces a highly distributed, buildingblock approach to network surveillance, attack isolation, and automated response. It combines models from research in distributed high-volume event-correlation methodologies with over a decade of intrusion detection research and engineering experience. The approach is novel in its use of highly distributed, independently tunable, surveillance and response monitors that are deployable polymorphically at various abstract layers in a large network. These monitors contribute to a streamlined event-analysis system that combines signature analysis with statistical profiling to provide localized real-time protection of the most widely used network services on the Internet. Equally important, EMERALD introduces a recursive framework for coordinating the dissemination of analyses from the distributed monitors to provide a global detection and response capability that can counter attacks occurring across an entire network enterprise. Further, EMERALD introduces a versatile application programmers' interface that enhances its ability to integrate with heterogeneous target hosts and provides a high degree of interoperability with third-party tool suites.