Which mitigation technique does a web application firewall use to protect a web server against...

Web Application Firewalls (WAFs) use rate-based rules as one of the primary mechanisms to detect and mitigate Distributed Denial of Service (DDoS) attacks. According to the SCAZT Study Guide, Section 3 (Network and Cloud Security, Pages 74–77), rate-based rules dynamically detect unusual spikes in traffic and can throttle or block connections exceeding predefined thresholds. This form of protection is more adaptive and intelligent than standard ACLs or static filtering, enabling protection against zero-day and volumetric attacks that may not follow known patterns.