Question 7

Explanation

Intrusion detection systems (IDS) are a type of detective access control. They monitor network traffic and system activity for malicious or policy-violating activity and report to a management station. An IDS can detect various attacks and probes, such as buffer overflows, stealth port scans, CGI attacks, SMB probes, and OS fingerprinting attempts (see ISC2 Study Guide, Domain 1).

The other options are wrong. Intrusion prevention systems (IPS) are preventive controls that detect potential security breaches and take action to prevent them from being accomplished. Turnstiles are physical access controls that restrict or control access to a site or location. Firewalls are preventive controls that protect a network by controlling inbound and outbound network traffic based on predetermined security rules.