Snort

Snort is an open-source network intrusion detection and prevention system that analyzes network traffic for malicious activity. It uses a combination of signature, protocol, and anomaly-based inspection methods to detect attacks. Snort can log, alert, and optionally block suspicious traffic in real-time. It supports extensive community and commercial rule sets for detecting new threats. Network security teams deploy Snort to protect infrastructure, monitor attacks, and improve incident response capabilities.