What is the function of an "intrusion detection system" (IDS)?

An intrusion detection system (IDS) is designed primarily to monitor network traffic for suspicious activity and potential threats. This function enables organizations to detect unauthorized access attempts, malicious code, and other security violations in real-time or by analyzing historical data. By identifying these anomalies, an IDS helps in safeguarding the integrity, confidentiality, and availability of network resources and data.

The importance of this capability lies in its proactive nature; by recognizing threats as they emerge, an IDS allows security personnel to take immediate action to mitigate risks, thus fortifying the organization against cyber attacks. An effective IDS can significantly enhance an organization's overall cybersecurity posture by providing alerts for investigation and improving response times to security incidents.

The other choices do not accurately represent the primary function of an IDS. Improving internet speed relates to network performance rather than security monitoring, providing backup focuses on data redundancy rather than threat detection, and enforcing access control policies involves managing user permissions rather than actively monitoring for intrusions.