what is waf

A Web Application Firewall (WAF) is a specific form of application firewall that filters, monitors, and blocks HTTP traffic to and from a web service. It is designed to protect web applications from a variety of application layer attacks such as cross-site scripting (XSS), SQL injection, and other vulnerabilities. By inspecting HTTP traffic, it can prevent unauthorized data from leaving the app and block malicious traffic from reaching the web application. A WAF operates as an intermediary between the user and the app itself, analyzing all communications before they reach the app or the server. It can be network-based, host-based, or cloud-based, and is often deployed through a reverse proxy and placed in front of one or more websites or applications. A WAF can be implemented in software or hardware, running in an appliance device, or in a typical server running a common operating system. It may be a stand-alone device or integrated into other network components. AWS WAF is an example of a cloud-based WAF that helps protect against common web exploits and bots that can affect availability, compromise security, or consume excessive resources.