What is the function of a web application firewall (WAF)?

A web application firewall (WAF) is primarily designed to filter and monitor HTTP traffic specifically for web applications. The role of a WAF is to protect web applications by analyzing and controlling incoming and outgoing web traffic based on a set of predetermined security rules. This includes identifying and mitigating various types of attacks, such as cross-site scripting (XSS), SQL injection, and other vulnerabilities that can be exploited through web interfaces.

By focusing on the application layer of the OSI model, a WAF ensures that web traffic is inspected and that potentially harmful requests or responses are blocked before they reach the web application itself. This proactive defense helps to protect sensitive data and maintain the integrity and availability of the application.

Other functions, such as data storage, encryption, and database access control, fall outside the primary purpose of a WAF. Therefore, while these elements are important for overall cybersecurity, they do not define the specific function of a web application firewall.