AWS Web Application Firewall (WAF) is a firewall security system that monitors incoming and outgoing traffic for applications and websites based on your pre-defined web security rules. AWS WAF defends applications and websites from common Web attacks that could otherwise damage application performance and availability and compromise security. You can create rules in AWS WAF that can include blocking specific HTTP headers, IP addresses, and URI strings. These rules prevent common web exploits, such as SQL injection or cross-site scripting. Once defined, new rules are deployed within seconds, and can easily be tracked so you can monitor their effectiveness via real-time insights. These saved metrics include URIs, IP addresses, and geo locations for each request.