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

The primary purpose of a web application firewall (WAF) is to filter and monitor HTTP traffic between a web application and the internet. A WAF is specifically designed to protect web applications from various types of attacks, including cross-site scripting (XSS), SQL injection, and other common web threats. By monitoring incoming and outgoing traffic, a WAF can identify and block malicious requests before they reach the application, effectively shielding it from exploitation.

In the context of cybersecurity, this focused filtering capability helps ensure that only legitimate traffic is allowed to interact with the web application. The WAF applies a set of rules to the traffic, which can be customized based on the specific needs of the web application being protected. This proactive defense is crucial for maintaining the security and integrity of sensitive web applications and the data they handle.

The other options do not align with the core functions of a WAF. While storing user credentials, optimizing page loading speed, and encrypting data in transit are all important aspects of web application security and performance, they fall outside the primary role of a web application firewall.