A Network-Based Intrusion Detection System (NIDS) monitors network traffic for suspicious activities and potential threats. It analyzes data packets traveling across the network to identify patterns that may indicate unauthorized access or attacks. By examining traffic in real-time, NIDS can quickly alert administrators to potential security breaches. NIDS typically uses various detection methods, including signature-based detection, which looks for known attack patterns, and anomaly-based detection, which identifies deviations from normal network behavior. This system is crucial for organizations to protect their network infrastructure and maintain the integrity of their data.