What does an intrusion detection system (IDS) primarily do?

An intrusion detection system (IDS) primarily monitors network activity for suspicious behavior. The fundamental purpose of an IDS is to detect and respond to potential threats by continuously analyzing traffic patterns and examining data packets for signs of malicious activity or policy violations. By identifying unauthorized access attempts, anomalies, or other indicators of compromise, the IDS serves as a critical component in enhancing the overall security posture of a network.

In contrast, optimizing network traffic focuses on improving performance and efficiency rather than security, protecting physical access to facilities is a matter of physical security rather than cybersecurity, and encrypting sensitive information is related to protecting data confidentiality rather than detecting intrusions. The role of an IDS is specifically tailored to enhancing security through vigilance and monitoring, which is why monitoring network activity is its primary function.