How WAF features differ with Azure Front Door, Azure Application Gateway and Azure CDN.

Azure WAF is a web application firewall that helps protect your web applications from common threats such as SQL injection, cross-site scripting, and other web exploits. You can define a WAF policy consisting of a combination of custom and managed rules to control access to your web applications.

Azure WAF on Azure Front Door:

Azure Front Door is a highly scalable, globally distributed application and content delivery network. Azure WAF, when integrated with Front Door, stops denial-of-service and targeted application attacks at the Azure network edge, close to attack sources before they enter your virtual network, offers protection without sacrificing performance.

Azure WAF on Application Gateway:

Azure Web Application Firewall (WAF) on Azure Application Gateway provides centralized protection of your web applications from common exploits and vulnerabilities like,SQL injection and cross-site scripting are among the most common attacks.

Azure WAF on Azure CDN:

Azure Web Application Firewall (WAF) on Azure Content Delivery Network (CDN) from Microsoft provides centralized protection for your web content. WAF defends your web services against common exploits and vulnerabilities. It keeps your service highly available for your users and helps you meet compliance requirements.

Here is a detailed differentiation on managed rule set of WAF across Azure services,

Note: Bot protection rule set is currently in public preview for Azure Application Gateway.